:root {
  --bg-base: #ffffff;
  --bg-main: #f6f8fb;
  --bg-main-gradient-end: #e9ecef;
  --bg-header: rgba(255, 255, 255, 0.98);
  --bg-main-card: rgba(255, 255, 255, 0.95);
  --bg-footer: #f2f4f7;
  --bg-card: rgba(255, 255, 255, 0.97);
  --bg-card-soft: rgba(255, 255, 255, 0.92);
  --bg-primary: #ffffff;
  --bg-secondary: #f9fafb;
  --bg-tertiary: #f3f4f6;
  --bg-elevated: #ffffff;
  --bg-overlay: rgba(0, 0, 0, 0.5);
  --bg-modal: rgba(255, 255, 255, 0.98);

  --card-bg: rgba(255, 255, 255, 0.4);
  --card-bg-hover: rgba(249, 250, 251, 0.4);
  --card-bg-active: rgba(243, 244, 246, 0.4);
  --card-bg-border: rgba(0, 0, 0, 0.08);
  --card-border: rgba(0, 0, 0, 0.10);
  --surface-1: rgba(255, 255, 255, 0.8);
  --surface-2: rgba(249, 250, 251, 0.8);
  --surface-3: rgba(243, 244, 246, 0.8);

  --text-main: #1a202c;
  --text-heading: #2d3748;
  --text-muted: #4a5568;
  --text-soft: #5a677a;
  --text-footer: #718096;
  --text-placeholder: #a0aec0;
  --text-primary: #0a0a0a;
  --text-secondary: #525252;
  --text-tertiary: #737373;
  --text-quaternary: #a3a3a3;
  --text-inverse: #ffffff;
  --text-link: #4353ff;
  --text-link-hover: #2d3acc;

  --accent: #3498db;
  --accent-dark: #2980b9;
  --accent-danger: #e74c3c;
  --accent-danger-dark: #c0392b;
  --accent-primary: #4353ff;
  --accent-primary-hover: #5865ff;
  --accent-primary-active: #2d3acc;
  --accent-primary-light: rgba(67, 83, 255, 0.1);
  --accent-primary-lighter: rgba(67, 83, 255, 0.05);
  --accent-secondary: #00d4aa;
  --accent-secondary-hover: #00e6bb;
  --accent-secondary-active: #00b899;
  --accent-purple: #9333ea;
  --accent-purple-hover: #a855f7;
  --accent-pink: #ec4899;
  --accent-pink-hover: #f472b6;
  --accent-orange: #f59e0b;
  --accent-orange-hover: #fbbf24;
  --accent-blue: #3b82f6;
  --accent-blue-hover: #60a5fa;
  --accent-teal: #14b8a6;
  --accent-teal-hover: #2dd4bf;

  --success: #10b981;
  --success-hover: #059669;
  --success-light: rgba(16, 185, 129, 0.1);
  --success-border: rgba(16, 185, 129, 0.3);
  --error: #ef4444;
  --error-hover: #dc2626;
  --error-light: rgba(239, 68, 68, 0.1);
  --error-border: rgba(239, 68, 68, 0.3);
  --warning: #f59e0b;
  --warning-hover: #d97706;
  --warning-light: rgba(245, 158, 11, 0.1);
  --warning-border: rgba(245, 158, 11, 0.3);
  --info: #3b82f6;
  --info-hover: #2563eb;
  --info-light: rgba(59, 130, 246, 0.1);
  --info-border: rgba(59, 130, 246, 0.3);

  --border-soft: rgba(0,0,0,0.08);
  --border-card: rgba(0,0,0,0.12);
  --border-input: rgba(0,0,0,0.15);
  --border-primary: rgba(0, 0, 0, 0.08);
  --border-secondary: rgba(0, 0, 0, 0.12);
  --border-tertiary: rgba(0, 0, 0, 0.16);
  --border-strong: rgba(0, 0, 0, 0.25);
  --border-focus: var(--accent-primary);
  --border-error: var(--error);
  --border-success: var(--success);

  --table-border: #d0d0d0;
  --table-header-bg: #e9e9e9;
  --table-row-alt: #f1f1f1;
  --blockquote-bg: #f7fafc;
  --blockquote-border: #4a5568;

  --card-shadow: 0 12px 35px rgba(0, 0, 0, 0.10);
  --shadow-soft: 0 20px 50px rgba(0,0,0,0.10);
  --shadow-card: 0 12px 35px rgba(0,0,0,0.10);
  --shadow-card-hover: 0 20px 55px rgba(0,0,0,0.18);
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 16px 48px rgba(0, 0, 0, 0.12);
  --shadow-2xl: 0 24px 64px rgba(0, 0, 0, 0.14);
  --shadow-3xl: 0 32px 80px rgba(0, 0, 0, 0.16);
  --shadow-inner: inset 0 2px 4px rgba(0, 0, 0, 0.06);
  --shadow-colored: 0 8px 32px rgba(67, 83, 255, 0.15);
  --shadow-colored-lg: 0 16px 48px rgba(67, 83, 255, 0.2);

  --backdrop-main: blur(8px) saturate(160%);
  --backdrop-header: blur(16px);

  --input-bg: rgba(255, 255, 255, 0.95);
  --input-bg-focus: #ffffff;
  --input-border: rgba(0, 0, 0, 0.15);
  --input-border-focus: #3498db;
  --input-shadow: 0 4px 20px rgba(0,0,0,0.08), inset 0 1px 0 rgba(255,255,255,0.6);
  --input-shadow-focus: 0 8px 32px rgba(0,0,0,0.12), 0 0 0 3px rgba(52,152,219,0.15);
  --input-placeholder: rgba(74,85,104,0.6);
  --input-placeholder-focus: rgba(74,85,104,0.4);

  --button-bg: #e2e8f0;
  --button-bg-hover: #cbd5e0;
  --button-bg-active: #a0aec0;

  --select-bg: rgba(255, 255, 255, 0.97);
  --select-bg-hover: rgba(255, 255, 255, 0.99);
  --select-bg-focus: #ffffff;
  --select-bg-active: rgba(248, 250, 252, 0.98);
  --select-border: rgba(0, 0, 0, 0.15);
  --select-border-focus: #3498db;
  --select-color: #2d3748;
  --select-color-focus: #1a202c;

  --label-color: #2d3748;

  --flashcard-bg: linear-gradient(145deg, #ffffff 0%, #f8fafc 100%);
  --flashcard-border: rgba(59,130,246,0.15);
  --flashcard-shadow: 0 10px 30px rgba(0,0,0,0.08), 0 4px 12px rgba(0,0,0,0.04);
  --question-bg: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --question-color: white;
  --answer-bg: #ffffff;
  --answer-border: rgba(0,0,0,0.06);
  --no-flashcards-color: #718096;
  --no-flashcards-link: #3b82f6;

  --study-day-bg: #ffffff;
  --study-day-border: rgba(0,0,0,0.08);
  --study-day-hover-border: rgba(52,152,219,0.3);
  --study-day-title: #2d3748;
  --study-task-bg: #f7fafc;
  --study-task-text: #4a5568;
  --study-task-strong: #2563eb;
  --study-task-minutes: #718096;

  --space-0: 0;
  --space-px: 1px;
  --space-0-5: 0.125rem;
  --space-1: 0.25rem;
  --space-1-5: 0.375rem;
  --space-2: 0.5rem;
  --space-2-5: 0.625rem;
  --space-3: 0.75rem;
  --space-3-5: 0.875rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-7: 1.75rem;
  --space-8: 2rem;
  --space-9: 2.25rem;
  --space-10: 2.5rem;
  --space-11: 2.75rem;
  --space-12: 3rem;
  --space-14: 3.5rem;
  --space-16: 4rem;
  --space-18: 4.5rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-28: 7rem;
  --space-32: 8rem;
  --space-36: 9rem;
  --space-40: 10rem;
  --space-44: 11rem;
  --space-48: 12rem;
  --space-52: 13rem;
  --space-56: 14rem;
  --space-60: 15rem;
  --space-64: 16rem;
  --space-72: 18rem;
  --space-80: 20rem;
  --space-96: 24rem;

  --font-sans: -apple-system, BlinkMacSystemFont, 'Inter', 'SF Pro Display', 'Segoe UI', system-ui, sans-serif;
  --font-serif: ui-serif, Georgia, Cambria, 'Times New Roman', Times, serif;
  --font-mono: 'SF Mono', 'Fira Code', 'Cascadia Code', 'Consolas', 'Courier New', monospace;
  --font-display: var(--font-sans);
  --text-2xs: 0.625rem;
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;
  --text-6xl: 3.75rem;
  --text-7xl: 4.5rem;
  --text-8xl: 6rem;
  --text-9xl: 8rem;
  --font-thin: 100;
  --font-extralight: 200;
  --font-light: 300;
  --font-normal: 400;
  --font-medium: 500;
  --font-semibold: 600;
  --font-bold: 700;
  --font-extrabold: 800;
  --font-black: 900;
  --leading-none: 1;
  --leading-tight: 1.25;
  --leading-snug: 1.375;
  --leading-normal: 1.5;
  --leading-relaxed: 1.625;
  --leading-loose: 2;
  --tracking-tighter: -0.05em;
  --tracking-tight: -0.025em;
  --tracking-normal: 0;
  --tracking-wide: 0.025em;
  --tracking-wider: 0.05em;
  --tracking-widest: 0.1em;

  --radius-none: 0;
  --radius-xs: 0.125rem;
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-3xl: 2rem;
  --radius-4xl: 3rem;
  --radius-full: 9999px;
  --border-0: 0;
  --border-1: 1px;
  --border-2: 2px;
  --border-4: 4px;
  --border-8: 8px;

  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slower: 500ms cubic-bezier(0.4, 0, 0.2, 1);
  --ease-linear: linear;
  --ease-in: cubic-bezier(0.4, 0, 1, 1);
  --ease-out: cubic-bezier(0, 0, 0.2, 1);
  --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);
  --ease-bounce: cubic-bezier(0.68, -0.55, 0.265, 1.55);
  --ease-smooth: cubic-bezier(0.25, 0.46, 0.45, 0.94);
  --duration-0: 0ms;
  --duration-75: 75ms;
  --duration-100: 100ms;
  --duration-150: 150ms;
  --duration-200: 200ms;
  --duration-300: 300ms;
  --duration-500: 500ms;
  --duration-700: 700ms;
  --duration-1000: 1000ms;

  --z-auto: auto;
  --z-0: 0;
  --z-10: 10;
  --z-20: 20;
  --z-30: 30;
  --z-40: 40;
  --z-50: 50;
  --z-dropdown: 1000;
  --z-sticky: 1100;
  --z-fixed: 1200;
  --z-modal-backdrop: 1300;
  --z-modal: 1400;
  --z-popover: 1500;
  --z-tooltip: 1600;
  --z-notification: 1700;
  --z-max: 9999;

  --container-xs: 20rem;
  --container-sm: 40rem;
  --container-md: 48rem;
  --container-lg: 64rem;
  --container-xl: 80rem;
  --container-2xl: 90rem;
  --container-full: 100rem;

  --header-height: 80px;
  --navbar-height: 64px;
  --footer-height: 400px;
  --sidebar-width: 280px;

  --blur-none: 0;
  --blur-sm: 4px;
  --blur-md: 8px;
  --blur-lg: 16px;
  --blur-xl: 24px;
  --blur-2xl: 40px;
  --blur-3xl: 64px;

  --opacity-0: 0;
  --opacity-5: 0.05;
  --opacity-10: 0.1;
  --opacity-20: 0.2;
  --opacity-25: 0.25;
  --opacity-30: 0.3;
  --opacity-40: 0.4;
  --opacity-50: 0.5;
  --opacity-60: 0.6;
  --opacity-70: 0.7;
  --opacity-75: 0.75;
  --opacity-80: 0.8;
  --opacity-90: 0.9;
  --opacity-95: 0.95;
  --opacity-100: 1;

  --chatbot-height: 700px;
  --chatbot-header-padding: 1.25rem 1.5rem;
  --chatbot-message-gap: 1.5rem;
  --chatbot-message-padding: 1rem 1.5rem;
  --chatbot-message-radius: 1.25rem;
  --chatbot-input-padding: 1.5rem;
  --chatbot-btn-size: 48px;
  --typing-dot-size: 6px;
  --typing-dot-gap: 4px;

  --badge-gap: 0.5rem;
  --badge-padding: 0.5rem 1rem;
  --badge-icon-size: 1.1rem;
  --badge-font-size: 0.9rem;

  --spotlight-max-width: 800px;
  --spotlight-margin-bottom: 3rem;
  --duckai-card-max-width: 700px;
  --duckai-card-padding: 3rem 2rem;
  --feature-tags-gap: 0.75rem;
  --tag-padding: 0.5rem 1.25rem;
  --tag-font-size: 0.85rem;

  --testimonial-min-width: 300px;
  --testimonial-margin-top: 4rem;
  --testimonial-padding: 2.5rem;
  --quote-icon-size: 3rem;
  --quote-icon-opacity: 0.2;
  --author-avatar-size: 48px;

  --cta-padding: 4rem 2rem;
  --cta-max-width: 800px;
  --cta-description-max-width: 600px;
  --cta-description-margin-bottom: 2.5rem;

  --step-gap: 1.5rem;
  --step-padding: 2rem;
  --step-padding-mobile: 1.5rem;
  --step-number-size: 3.5rem;
  --step-arrow-size: 2.5rem;
  --step-arrow-padding: 0 1rem;

  --header-nav-gap: 2rem;
  --header-nav-gap-tablet: 1.5rem;
  --header-nav-gap-mobile: 1rem;
  --header-nav-padding: 1.5rem 2rem;
  --header-nav-padding-tablet: 1.25rem 1.5rem;
  --header-nav-padding-mobile: 1rem 1.25rem;
  --header-nav-padding-small: 0.75rem 1rem;
  --header-nav-min-height: 100px;
  --header-nav-min-height-tablet: 90px;
  --header-nav-min-height-mobile: 80px;
  --header-nav-min-height-small: 70px;
  --header-max-width: 80rem;
  --header-redirect-gap: 0.75rem;
  --header-redirect-padding: 0.75rem 1.5rem;
  --header-redirect-radius: 1rem;
  --header-redirect-mobile-size: 44px;
  --donate-icon-size: 20px;
  --header-text-gap: 1rem;
  --brand-icon-size: 1.6em;
  --brand-icon-size-mobile: 1.4em;
  --header-actions-gap: 1.25rem;
  --auth-links-gap: 1rem;
  --auth-links-gap-mobile: 0.5rem;

  --button-padding: 0.75rem 1.25rem;
  --button-padding-primary: 0.75rem 1.5rem;
  --button-padding-large: 1.25rem 3rem;
  --button-padding-mobile: 0.5rem 1rem;
  --button-radius: 0.75rem;
  --button-gap: 0.5rem;
  --button-min-width-large: 200px;

  --user-menu-padding: 0.25rem 0.75rem 0.25rem 0.25rem;
  --user-menu-gap: 0.5rem;
  --user-avatar-size: 32px;
  --menu-chevron-size: 0.8rem;
  --free-uses-padding: 0.625rem 1rem;
  --free-uses-gap: 0.5rem;

  --footer-padding: 4rem 2rem;
  --footer-font-size: 0.95rem;

  --orb-size: 80vh;
  --orb-blur: 100px;
  --orb-opacity: 0.8;

  --float-distance: 3px;
  --float-translate: 50px 30px;
  --float-scale: 1.05;

  --grid-gap-large: 4rem;
  --section-padding: 6rem 0;
  --max-width-content: 85%;

  --translateY-hover: -4px;
  --translateY-hover-large: -5px;
  --scale-hover: 1.05;
  --scale-hover-large: 1.03;
  --rotate-hover: 5deg;
  --rotate-arrow-mobile: 90deg;
}

body.dark,
[data-theme="dark"] {
  --bg-base: #0a0a0a;
  --bg-main: #050710;
  --bg-main-gradient-end: #050710;
  --bg-header: rgba(7, 10, 24, 0.96);
  --bg-main-card: rgba(13, 16, 33, 0.96);
  --bg-footer: #050712;
  --bg-card: #0d101b;
  --bg-card-soft: #141826;
  --bg-primary: #1a1a1a;
  --bg-secondary: #242424;
  --bg-tertiary: #2e2e2e;
  --bg-elevated: #333333;
  --bg-overlay: rgba(0, 0, 0, 0.85);
  --bg-modal: rgba(10, 10, 10, 0.95);

  --card-bg: rgba(30, 30, 30, 0.4);
  --card-bg-hover: rgba(38, 38, 38, 0.4);
  --card-bg-active: rgba(42, 42, 42, 0.4);
  --card-bg-border: rgba(255, 255, 255, 0.08);
  --card-border: #232941;

  --text-main: #f5f7ff;
  --text-heading: #ffffff;
  --text-muted: #c3c7d9;
  --text-soft: #a7aec4;
  --text-footer: #9aa1bc;
  --text-placeholder: #6c7190;
  --text-primary: #ffffff;
  --text-secondary: #a0a0a0;
  --text-tertiary: #707070;
  --text-quaternary: #4a4a4a;
  --text-inverse: #0a0a0a;
  --text-link: #4353ff;
  --text-link-hover: #5865ff;

  --accent: #4aa8ff;
  --accent-dark: #1f6fd1;
  --accent-danger: #ff6b6b;
  --accent-danger-dark: #e63946;
  --accent-primary: #6366f1;
  --accent-primary-hover: #818cf8;

  --border-soft: rgba(255,255,255,0.14);
  --border-card: rgba(255,255,255,0.12);
  --border-input: rgba(255,255,255,0.18);
  --border-primary: rgba(255, 255, 255, 0.1);
  --border-secondary: rgba(255, 255, 255, 0.15);
  --border-tertiary: rgba(255, 255, 255, 0.2);
  --border-strong: rgba(255, 255, 255, 0.3);

  --table-border: #2d3554;
  --table-header-bg: #181d34;
  --table-row-alt: #141a2b;

  --blockquote-bg: #171d33;
  --blockquote-border: #4a86ff;

  --shadow-soft: 0 25px 60px rgba(0,0,0,0.8);
  --shadow-card: 0 20px 45px rgba(0,0,0,0.75);
  --shadow-card-hover: 0 28px 70px rgba(0,0,0,0.9);
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.5);
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.6);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.7);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.8);
  --shadow-xl: 0 16px 48px rgba(0, 0, 0, 0.85);
  --shadow-2xl: 0 24px 64px rgba(0, 0, 0, 0.9);
  --shadow-3xl: 0 32px 80px rgba(0, 0, 0, 0.95);
  --shadow-inner: inset 0 2px 4px rgba(0, 0, 0, 0.6);
  --shadow-colored: 0 8px 32px rgba(67, 83, 255, 0.3);
  --shadow-colored-lg: 0 16px 48px rgba(67, 83, 255, 0.4);

  --backdrop-main: blur(12px);
  --backdrop-header: blur(24px);

  --input-bg: rgba(12,16,32,0.85);
  --input-bg-focus: rgba(25,34,73,0.95);
  --input-border: rgba(255,255,255,0.18);
  --input-border-focus: rgba(74,134,255,0.9);
  --input-shadow: 0 10px 40px rgba(0,0,0,0.75), inset 0 1px 0 rgba(255,255,255,0.04);
  --input-shadow-focus: 0 18px 55px rgba(0,0,0,0.95), 0 0 35px rgba(74,134,255,0.5), inset 0 1px 0 rgba(0,0,0,0.6);

  --button-bg: rgb(60,68,92);
  --button-bg-hover: rgba(90,108,160,0.95);
  --button-bg-active: rgba(46,56,92,0.98);

  --select-bg: rgba(35,42,76,0.95);
  --select-bg-hover: rgba(52,63,104,0.98);
  --select-bg-focus: rgba(40,54,104,0.98);
  --select-bg-active: rgba(28,37,78,0.95);
  --select-border: #5a6ca0;
  --select-border-focus: #4a86ff;
  --select-color: #e5e9ff;
  --select-color-focus: #ffffff;

  --label-color: rgba(230,235,255,0.9);

  --flashcard-bg: linear-gradient(145deg,#141826,#0d101b);
  --flashcard-border: rgba(74,134,255,0.2);
  --flashcard-shadow: 0 18px 45px rgba(0,0,0,0.85);
  --question-bg: linear-gradient(135deg,#667eea 0%,#764ba2 100%);
  --question-color: #f5f7ff;
  --answer-bg: #101321;
  --answer-border: rgba(255,255,255,0.05);
  --no-flashcards-color: #9aa1bc;
  --no-flashcards-link: #4aa8ff;

  --study-day-bg: #101321;
  --study-day-border: rgba(255,255,255,0.1);
  --study-day-hover-border: rgba(74,134,255,0.4);
  --study-day-title: #f5f7ff;
  --study-task-bg: rgba(255,255,255,0.05);
  --study-task-text: #e5e9ff;
  --study-task-strong: #6ee7ff;
  --study-task-minutes: #9aa1bc;
}

body {
  background-color: var(--bg-primary);
  background-image:
    radial-gradient(circle at 15% 50%, rgba(67, 83, 255, 0.12), transparent 30%),
    radial-gradient(circle at 85% 30%, rgba(236, 72, 153, 0.12), transparent 30%);
  background-attachment: fixed;
  animation: subtlePulse 10s ease-in-out infinite alternate;
  min-height: 100vh;
}
@keyframes subtlePulse {
  0% { background-position: 0% 0%; }
  100% { background-position: 10px 10px; }
}
[data-theme="dark"] body, body.dark {
  background-color: #050505;
  background-image:
    radial-gradient(circle at 15% 50%, rgba(67, 83, 255, 0.18), transparent 35%),
    radial-gradient(circle at 85% 30%, rgba(236, 72, 153, 0.15), transparent 35%);
}
body::before, body::after {
  content: ''; position: fixed; width: var(--orb-size); height: var(--orb-size); border-radius: 50%;
  filter: blur(var(--orb-blur));
  z-index: -1;
  opacity: var(--orb-opacity);
  pointer-events: none;
  animation: floatOrbSlow 30s infinite alternate cubic-bezier(0.4, 0, 0.2, 1);
}
body::before { background: rgba(67, 83, 255, 0.1); top: -20%; left: -10%; }
body::after { background: rgba(0, 212, 170, 0.1); bottom: -20%; right: -10%; animation-delay: -15s; }
[data-theme="dark"] body::before { background: rgba(67, 83, 255, 0.15); }
[data-theme="dark"] body::after { background: rgba(0, 212, 170, 0.15); }
@keyframes floatOrbSlow { 0% { transform: translate(0, 0) scale(1); } 100% { transform: translate(50px, 30px) scale(var(--scale-hover)); } }
.card, .stat-card, .feature-card, .testimonial-card, .chatbot-container, .duckai-card, .step-card, .duckai-feature-card {
  background: var(--card-bg);
  backdrop-filter: blur(20px) saturate(100%);
  -webkit-backdrop-filter: blur(20px) saturate(100%);
  border: 1px solid rgba(0, 0, 0, 0.04);
  box-shadow: 0 4px 24px -2px rgba(0, 0, 0, 0.02);
}
[data-theme="dark"] .card, [data-theme="dark"] .stat-card, [data-theme="dark"] .feature-card,
[data-theme="dark"] .chatbot-container, [data-theme="dark"] .duckai-card, [data-theme="dark"] .step-card,
[data-theme="dark"] .benefit-card,
[data-theme="dark"] .testimonial-card {
  background: var(--card-bg)
}
[data-theme="dark"] .duckai-feature-card {
  border: 1px solid rgba(255, 255, 255, 0.05);
  box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.2);
}
.center-content { display: flex; justify-content: center; align-items: center; flex-direction: column; text-align: center; }
.duckai-text-gradient {
  background: linear-gradient(135deg, #4353ff 0%, #ec4899 100%);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; font-weight: 800;
}
.chatbot-container { display: flex; flex-direction: column; width: 100%; height: var(--chatbot-height); border-radius: 1.5rem; overflow: hidden; border: 1px solid rgba(0,0,0,0.05); transition: transform 0.3s ease, box-shadow 0.3s ease; }
.chatbot-container:hover { transform: translateY(var(--translateY-hover)); box-shadow: 0 24px 48px -12px rgba(67, 83, 255, 0.1); }
.chatbot-header { padding: var(--chatbot-header-padding); border-bottom: 1px solid rgba(0, 0, 0, 0.05); display: flex; align-items: center; justify-content: space-between; background: rgba(255, 255, 255, 0.5); }
[data-theme="dark"] .chatbot-header { border-bottom-color: rgba(255, 255, 255, 0.05); background: rgba(0, 0, 0, 0.2); }
.chatbot-messages { flex: 1; padding: var(--step-padding); overflow-y: auto; display: flex; flex-direction: column; gap: var(--chatbot-message-gap); }
.message { display: flex; gap: var(--auth-links-gap); max-width: var(--max-width-content); opacity: 0; transform: translateY(10px); animation: messageSlideIn 0.3s ease forwards; }
@keyframes messageSlideIn { to { opacity: 1; transform: translateY(0); } }
.message-user { align-self: flex-end; flex-direction: row-reverse; }
.message-bot { align-self: flex-start; }
.message-content { padding: var(--chatbot-message-padding); border-radius: var(--chatbot-message-radius); font-size: 1rem; line-height: 1.6; position: relative; }
.message-user .message-content { background: linear-gradient(135deg, #4353ff, #ec4899); color: white; border-bottom-right-radius: 4px; }
.message-bot .message-content { background: rgba(255, 255, 255, 0.8); border: 1px solid rgba(0, 0, 0, 0.06); color: var(--text-primary); border-bottom-left-radius: 4px; }
[data-theme="dark"] .message-bot .message-content { background: rgba(30, 30, 36, 0.8); border-color: rgba(255, 255, 255, 0.08); }
.chatbot-input-area { padding: var(--chatbot-input-padding); background: rgba(255, 255, 255, 0.6); border-top: 1px solid rgba(0, 0, 0, 0.05); display: flex; gap: var(--auth-links-gap); align-items: center; }
[data-theme="dark"] .chatbot-input-area { background: rgba(20, 20, 20, 0.6); border-top-color: rgba(255, 255, 255, 0.05); }
.chatbot-input { width: 100%; background: var(--bg-secondary); border: 1px solid transparent; border-radius: 9999px; padding: var(--chatbot-message-padding); font-size: 1rem; color: var(--text-primary); outline: none; transition: all 0.2s; }
.chatbot-input:focus { background: var(--bg-base); border-color: var(--accent-primary); box-shadow: 0 0 0 4px rgba(67, 83, 255, 0.1); }
.chatbot-send-btn { width: var(--chatbot-btn-size); height: var(--chatbot-btn-size); border-radius: 50%; background: var(--accent-primary); color: white; border: none; display: flex; align-items: center; justify-content: center; cursor: pointer; transition: all 0.2s; }
.chatbot-send-btn:hover { transform: scale(var(--scale-hover)); background: var(--accent-primary-hover); }
.typing-indicator { display: flex; gap: var(--typing-dot-gap); padding: 0.5rem; }
.typing-dot { width: var(--typing-dot-size); height: var(--typing-dot-size); background: var(--text-tertiary); border-radius: 50%; animation: typingBounce 1.4s infinite ease-in-out both; }
.typing-dot:nth-child(1) { animation-delay: -0.32s; } .typing-dot:nth-child(2) { animation-delay: -0.16s; }
@keyframes typingBounce { 0%, 80%, 100% { transform: scale(0); } 40% { transform: scale(1); } }
.free-tier-badge {
    display: inline-flex; align-items: center; gap: var(--badge-gap); padding: var(--badge-padding);
    background: rgba(67, 83, 255, 0.1); color: var(--accent-primary);
    border: 1px solid rgba(67, 83, 255, 0.2); border-radius: 9999px;
    font-weight: 600; font-size: var(--badge-font-size); margin-bottom: 1rem;
}
.badge-icon { display: inline-flex; align-items: center; justify-content: center; font-size: var(--badge-icon-size); }
.spotlight-content { text-align: center; max-width: var(--spotlight-max-width); margin: 0 auto var(--spotlight-margin-bottom) auto; }
.spotlight-title {
    font-size: clamp(2.5rem, 5vw, 3.5rem);
    background: linear-gradient(135deg, #4353ff 0%, #ec4899 100%);
    -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
    margin-bottom: 1rem; display: inline-block;
}
.spotlight-subtitle { font-size: var(--text-xl); color: var(--text-secondary); margin-bottom: 1rem; }
.spotlight-description { font-size: var(--badge-icon-size); color: var(--text-tertiary); line-height: 1.6; }
.duckai-feature-card {
    text-align: center; max-width: var(--duckai-card-max-width); margin: 0 auto; padding: var(--duckai-card-padding);
    box-shadow: 0 20px 60px -10px rgba(67, 83, 255, 0.15); border-radius: 2rem;
    display: flex; flex-direction: column; align-items: center;
}
[data-theme="dark"] .duckai-feature-card,
body.dark .benefit-card,
body.dark .testimonial-card,
body.dark .stat-card,
body.dark .feature-card,
body.dark .step-card {
  background: var(--card-bg) !important;
}
[data-theme="dark"] .duckai-icon, body.dark .duckai-icon {
    background: #111111 !important;
    border: 1px solid #333333 !important;
    box-shadow: none !important;
}
[data-theme="dark"] .duckai-feature-card h3 a, body.dark .duckai-feature-card h3 a { color: #ffffff !important; }
[data-theme="dark"] .duckai-feature-card p, body.dark .duckai-feature-card p { color: #cccccc !important; }
.feature-tags { display: flex; flex-wrap: wrap; justify-content: center; gap: var(--feature-tags-gap); margin-top: auto; }
.tag, .tag-special, .feature-tags span {
    display: inline-flex !important; align-items: center; justify-content: center;
    padding: var(--tag-padding) !important; border-radius: 9999px !important;
    font-size: var(--tag-font-size); font-weight: 600; transition: all 0.2s; line-height: 1;
}
.tag { background: var(--bg-tertiary); color: var(--text-secondary); border: 1px solid rgba(0,0,0,0.05); }
.tag-special {
    background: linear-gradient(135deg, rgba(67, 83, 255, 0.1), rgba(236, 72, 153, 0.1));
    border: 1px solid rgba(67, 83, 255, 0.2); color: var(--accent-primary);
}
[data-theme="dark"] .tag, body.dark .tag { background: rgba(42, 42, 42, 0.8); color: #e0e0e0; border-color: rgba(255,255,255,0.1); }
[data-theme="dark"] .tag-special, body.dark .tag-special {
    background: #111111 !important; color: #ffffff !important; border: 1px solid #333333 !important;
}
[data-theme="dark"] .tag-special:hover { border-color: var(--accent-primary) !important; background: #222222 !important; }
.grid, .features-grid, .testimonials-grid, .benefits-grid, div[class*="grid"] { display: grid !important; gap: var(--grid-gap-large) !important; }
section { padding: var(--section-padding) !important; }
.testimonials-grid { grid-template-columns: repeat(auto-fit, minmax(var(--testimonial-min-width), 1fr)); margin-top: var(--testimonial-margin-top); }
.testimonial-card { display: flex; flex-direction: column; height: 100%; padding: var(--testimonial-padding); border-radius: 1.5rem; }
.quote-icon { font-size: var(--quote-icon-size); line-height: 1; color: var(--accent-primary); opacity: var(--quote-icon-opacity); margin-bottom: 1rem; font-family: serif; }
.testimonial-text { font-size: var(--badge-icon-size); color: var(--text-primary); line-height: 1.6; flex-grow: 1; margin-bottom: 2rem; font-style: italic; }
.testimonial-author { display: flex; align-items: center; gap: var(--auth-links-gap); margin-top: auto; }
.author-avatar {
    width: var(--chatbot-btn-size); height: var(--chatbot-btn-size); border-radius: 50%; background: linear-gradient(135deg, #4353ff, #ec4899); color: white;
    display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: var(--text-xl); box-shadow: 0 4px 10px rgba(67, 83, 255, 0.2);
}
.author-name { font-weight: 600; color: var(--text-primary); font-size: 1rem; }
.cta-content {
    display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center;
    padding: var(--cta-padding); max-width: var(--spotlight-max-width); margin: 0 auto;
    border-radius: 2rem; border: 1px solid rgba(67, 83, 255, 0.1); backdrop-filter: blur(20px);
}
.cta-title { font-size: clamp(2rem, 4vw, 3rem); font-weight: 800; margin-bottom: 1rem; color: var(--text-primary); }
.cta-description { font-size: var(--text-xl); color: var(--text-secondary); margin-bottom: var(--cta-description-margin-bottom); max-width: var(--cta-description-max-width); }
.step-card { display: flex; flex-direction: row; align-items: flex-start; gap: var(--chatbot-message-gap); padding: var(--step-padding); height: 100%; transition: transform 0.3s ease; }
.step-card:hover { transform: translateY(var(--translateY-hover-large)); border-color: var(--accent-primary); }
.step-number { flex-shrink: 0; width: var(--step-number-size); height: var(--step-number-size); background: linear-gradient(135deg, #4353ff, #ec4899); color: white; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-weight: 800; font-size: var(--text-2xl); box-shadow: 0 4px 12px rgba(67, 83, 255, 0.3); }
.step-content { gap: var(--badge-gap); text-align: left;}
.step-content h3 { margin: 0; font-size: var(--text-xl); font-weight: 700; color: var(--text-primary); }
.step-content p { margin: 0; font-size: 1rem; color: var(--text-secondary); line-height: 1.5; }
.step-arrow { display: flex; align-items: center; justify-content: center; font-size: var(--step-arrow-size); color: var(--accent-primary); opacity: 0.4; padding: var(--step-arrow-padding); }
@media (max-width: 768px) { .step-arrow { transform: rotate(var(--rotate-arrow-mobile)); padding: 1rem; } .step-card { padding: var(--chatbot-input-padding); } }
.header {
  position: sticky; top: 0; width: 100%; z-index: 1100;
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px); 
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.08); transition: all 0.3s ease;
}
[data-theme="dark"] .header, body.dark .header {
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
}
.header.scrolled { box-shadow: 0 12px 48px rgba(0, 0, 0, 0.12); backdrop-filter: blur(30px); }
.header-nav {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: var(--header-nav-gap);
  padding: var(--chatbot-input-padding) 2rem;
  width: 100%;
  margin: 0;
  position: relative;
  z-index: 10;
  min-height: var(--header-nav-min-height);
}
.header-redirect {
  justify-self: start; display: inline-flex; align-items: center; gap: var(--feature-tags-gap);
  color: var(--text-primary); font-size: 1rem; font-weight: 600; text-decoration: none;
  padding: var(--header-redirect-padding); border-radius: var(--header-redirect-radius);
  background: linear-gradient(135deg, rgba(67, 83, 255, 0.1), rgba(236, 72, 153, 0.1));
  border: 2px solid rgba(0,0,0,0.05); transition: all 0.3s ease; box-shadow: 0 4px 12px rgba(67, 83, 255, 0.1);
}
.header-redirect:hover {
  background: linear-gradient(135deg, rgba(67, 83, 255, 0.2), rgba(236, 72, 153, 0.2));
  border-color: var(--accent-primary); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(67, 83, 255, 0.2);
}
.header-redirect:active { transform: translateY(0); }
.donate-icon { width: var(--donate-icon-size); height: var(--donate-icon-size); color: var(--accent-primary); transition: color 0.2s ease; }
.header-redirect:hover .donate-icon { color: #ec4899; filter: drop-shadow(0 0 8px rgba(236, 72, 153, 0.6)); }
.header-brand { display: flex; justify-content: center; align-items: center; grid-column: 2; }
.header-text {
  display: inline-flex; align-items: center; gap: var(--auth-links-gap); color: var(--text-primary);
  font-size: clamp(1.5rem, 4vw, 2.25rem); font-weight: 800; line-height: 1.25; margin: 0;
  transition: all 0.3s ease; text-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}
.header-text a {
  color: inherit; text-decoration: none; display: inline-flex; align-items: center; gap: var(--feature-tags-gap); transition: all 0.3s ease;
}
.header-text a:hover { color: var(--accent-primary); text-shadow: 0 4px 16px rgba(67, 83, 255, 0.4); }
.brand-icon { font-size: var(--brand-icon-size); line-height: 1; transition: all 0.3s ease; filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1)); }
.header-text a:hover .brand-icon { transform: scale(1.1) rotate(var(--rotate-hover)); filter: drop-shadow(0 4px 12px rgba(67, 83, 255, 0.6)); }
@keyframes subtle-float { 0%, 100% { transform: translateY(0px); } 50% { transform: translateY(-3px); } }
.brand-icon { animation: subtle-float 3s ease-in-out infinite; }
@media (prefers-reduced-motion: reduce) { .brand-icon { animation: none; } }
.header-actions { justify-self: end; display: flex; align-items: center; justify-content: flex-end; gap: var(--header-actions-gap); }
.auth-links { display: flex; align-items: center; gap: var(--auth-links-gap); }
.header-link, .button-ghost, .button-secondary, .cta-secondary {
  color: var(--text-primary); font-size: 1rem; font-weight: 600; text-decoration: none;
  padding: var(--button-padding); border-radius: var(--button-radius); transition: all 0.3s ease; position: relative; overflow: hidden;
  background: transparent; border: 1px solid transparent;
}
.header-link:hover, .button-ghost:hover, .button-secondary:hover, .cta-secondary:hover {
  color: var(--accent-primary) !important;
  background: rgba(67, 83, 255, 0.05);
  transform: translateY(-2px);
}
.header-link-primary, .button-primary, .cta-primary, .cta-large, a.cta-button.cta-large {
  background: linear-gradient(135deg, #4353ff, #ec4899) !important;
  color: #ffffff !important; -webkit-text-fill-color: #ffffff !important; background-clip: border-box !important;
  border: none !important; box-shadow: 0 8px 24px rgba(67, 83, 255, 0.3);
  position: relative; overflow: hidden;
  display: inline-flex; align-items: center; justify-content: center; gap: var(--badge-gap);
  font-weight: 700; text-decoration: none; padding: var(--header-redirect-padding); border-radius: var(--button-radius); z-index: 1;
}
.cta-large {
    padding: var(--button-padding-large) !important; font-size: var(--text-xl); min-width: var(--button-min-width-large);
    transition: transform 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275), box-shadow 0.4s ease;
}
.header-link-primary:hover, .button-primary:hover, .cta-primary:hover, .cta-large:hover, a.cta-button.cta-large:hover {
  background: linear-gradient(135deg, #5865ff, #f472b6) !important;
  color: #ffffff !important; -webkit-text-fill-color: #ffffff !important;
  transform: translateY(-2px);
  box-shadow: 0 12px 36px rgba(67, 83, 255, 0.4), 0 0 40px rgba(236, 72, 153, 0.3);
  opacity: 1 !important;
}
.cta-large:hover {
    transform: translateY(var(--translateY-hover-large)) scale(var(--scale-hover-large));
    box-shadow: 0 20px 50px -10px rgba(67, 83, 255, 0.5), 0 0 30px rgba(236, 72, 153, 0.4);
}
.user-menu-toggle { padding: 0.25rem 0.75rem 0.25rem 0.25rem !important; gap: var(--badge-gap) !important; min-height: auto !important; }
.user-avatar { width: var(--user-avatar-size) !important; height: var(--user-avatar-size) !important; border-width: 1px !important; }
.menu-chevron { font-size: var(--menu-chevron-size) !important; }
.divider { color: var(--text-tertiary); font-size: 1rem; user-select: none; opacity: 0.5; }
.free-uses {
  color: var(--accent-primary); font-size: 0.875rem; font-weight: 700; padding: var(--free-uses-padding);
  background: linear-gradient(135deg, rgba(67, 83, 255, 0.15), rgba(0, 212, 170, 0.15));
  border: 2px solid var(--accent-primary); border-radius: 9999px; white-space: nowrap;
  display: inline-flex; align-items: center; gap: var(--badge-gap); box-shadow: 0 4px 12px rgba(67, 83, 255, 0.2);
  animation: pulse-glow 2s ease-in-out infinite;
}
@keyframes pulse-glow { 0%, 100% { box-shadow: 0 4px 12px rgba(67, 83, 255, 0.2); } 50% { box-shadow: 0 4px 20px rgba(67, 83, 255, 0.4), 0 0 30px rgba(67, 83, 255, 0.2); } }

.user-menu-wrapper {
  position: relative;
}

.user-menu {
  position: absolute !important;
  right: 0 !important;
  top: 100% !important;
  left: auto !important;
  margin-top: 0.5rem !important;
  width: 16rem !important;
  background: var(--bg-card) !important;
  border: 1px solid var(--border-primary) !important;
  border-radius: 0.5rem !important;
  box-shadow: var(--shadow-xl) !important;
  opacity: 0 !important;
  pointer-events: none !important;
  transition: opacity 0.2s ease, transform 0.2s ease !important;
  transform: translateY(-10px) !important;
  z-index: var(--z-dropdown) !important;
}

.user-menu.dropdown-open {
  opacity: 1 !important;
  pointer-events: auto !important;
  transform: translateY(0) !important;
}

.menu-header {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--border-primary);
}

.usage-badge {
    white-space: normal !important;
    text-align: center;
    line-height: 1.4;
}

.badge-icon {
  width: 1rem;
  height: 1rem;
}

.dropdown-item {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  color: var(--text-primary);
  text-decoration: none;
  transition: background-color 0.2s ease;
}

.dropdown-item:hover {
  background: var(--bg-secondary);
}

.dropdown-item.danger {
  color: var(--error);
}

.dropdown-item.danger:hover {
  background: var(--error-light);
}

.menu-icon {
  width: 1.125rem;
  height: 1.125rem;
  stroke: currentColor;
}

.menu-divider {
  margin: 0.5rem 0;
  border: 0;
  border-top: 1px solid var(--border-primary);
}

@media (max-width: 1024px) { .header-nav {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: var(--header-nav-gap);
  padding: var(--chatbot-input-padding) 2rem;
  width: 100%;
  margin: 0;
  position: relative;
  z-index: 10;
  min-height: var(--header-nav-min-height);
} }
@media (max-width: 768px) {
  .header-nav {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: var(--header-nav-gap);
  padding: var(--chatbot-input-padding) 2rem;
  width: 100%;
  margin: 0;
  position: relative;
  z-index: 10;
  min-height: var(--header-nav-min-height);
}
  .header-text { font-size: var(--text-2xl); } .brand-icon { font-size: var(--brand-icon-size-mobile); }
  .free-uses { display: none; } .header-redirect span { display: none; }
  .header-redirect { padding: 0.75rem; width: 44px; height: 44px; justify-content: center; }
}
@media (max-width: 480px) {
  .header-nav {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: var(--header-nav-gap);
  padding: var(--chatbot-input-padding) 2rem;
  width: 100%;
  margin: 0;
  position: relative;
  z-index: 10;
  min-height: var(--header-nav-min-height);
} .header-text { font-size: var(--text-xl); }
  .auth-links { gap: var(--badge-gap); } .header-link { padding: var(--badge-padding); font-size: 0.875rem; }
  .divider { display: none; }
}
footer {
  margin-top: auto;
  padding: var(--cta-padding);
  width: 100%;
  text-align: center;
  border-top: 1px solid rgba(0, 0, 0, 0.06);
  position: relative;
  z-index: 10;
  background: var(--card-bg);
  backdrop-filter: blur(10px);
}
[data-theme="dark"] footer, body.dark footer {
  background: rgba(30 , 30 , 30 , 0.4);
  border-top: 1px solid rgba(255,255,255,0.05);
}
footer p {
  font-size: var(--footer-font-size);
  color: var(--text-secondary);
  margin-bottom: 1rem;
}
.repoLink {
  color: var(--accent-primary);
  font-weight: 600;
  text-decoration: none;
  transition: all 0.2s ease;
}
.repoLink:hover {
  color: var(--accent-primary-hover);
  text-decoration: underline;
}
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  border: 0 solid var(--border-primary);
}
html {
  font-size: 16px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  -webkit-text-size-adjust: 100%;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
  tab-size: 4;
  -webkit-tap-highlight-color: transparent;
}
body {
  font-family: var(--font-sans);
  font-size: var(--text-base, 1rem);
  font-weight: var(--font-normal, 400);
  line-height: var(--leading-normal);
  color: var(--text-primary);
  background-color: var(--bg-base);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  transition: background-color var(--transition-base), color var(--transition-base, 250ms);
}
button, input, optgroup, select, textarea {
  font-family: inherit;
  font-size: 100%;
  line-height: inherit;
  color: inherit;
  margin: 0;
  padding: 0;
}
button, select {
  text-transform: none;
}
button, [type='button'], [type='reset'], [type='submit'] {
  -webkit-appearance: button;
  background-color: transparent;
  background-image: none;
}
button {
  cursor: pointer;
  border: none;
  background: none;
  padding: 0;
}
button:disabled {
  cursor: not-allowed;
  opacity: var(--opacity-50);
}
ul, ol {
  list-style: none;
  margin: 0;
  padding: 0;
}
a {
  color: inherit;
  text-decoration: none;
  background-color: transparent;
}
img, svg, video, canvas, audio, iframe, embed, object {
  display: block;
  vertical-align: middle;
  max-width: 100%;
  height: auto;
}
svg {
  fill: currentColor;
}
table {
  border-collapse: collapse;
  border-spacing: 0;
  width: 100%;
}
fieldset {
  border: 0;
  padding: 0;
  margin: 0;
  min-width: 0;
}
legend {
  padding: 0;
  display: table;
}
textarea {
  resize: vertical;
  overflow: auto;
}
input::placeholder,
textarea::placeholder {
  opacity: 1;
  color: var(--text-muted);
}
h1, h2, h3, h4, h5, h6 {
  font-weight: var(--font-bold, 700);
  line-height: var(--leading-tight);
  letter-spacing: var(--tracking-tight);
  color: var(--text-primary);
  margin: 0 0 var(--space-6, 1.5rem);
  text-wrap: balance;
}
h1 {
  font-size: clamp(2.5rem, 5vw + 1rem, 5rem);
  font-weight: var(--font-extrabold, 800);
  letter-spacing: var(--tracking-tighter);
  line-height: var(--leading-none);
}
h2 {
  font-size: clamp(2rem, 4vw + 1rem, 3.75rem);
  font-weight: var(--font-bold, 700);
  line-height: 1.1;
}
h3 {
  font-size: clamp(1.5rem, 3vw + 0.5rem, 2.25rem);
  font-weight: var(--font-bold, 700);
  line-height: var(--leading-tight);
}
h4 {
  font-size: clamp(1.25rem, 2vw + 0.5rem, 1.875rem);
  font-weight: var(--font-semibold, 600);
}
h5 {
  font-size: var(--text-xl, 1.25rem);
  font-weight: var(--font-semibold, 600);
}
h6 {
  font-size: var(--text-lg, 1.125rem);
  font-weight: var(--font-medium, 500);
}
p {
  margin: 0 0 var(--space-4, 1rem);
  color: var(--text-secondary);
  line-height: var(--leading-relaxed);
  font-size: var(--text-base, 1rem);
  text-wrap: pretty;
}
p:last-child {
  margin-bottom: 0;
}
strong, b {
  font-weight: var(--font-semibold, 600);
  color: var(--text-primary);
}
em, i {
  font-style: italic;
}
small {
  font-size: var(--text-sm, 0.875rem);
  color: var(--text-tertiary);
}
mark {
  background-color: rgba(67, 83, 255, 0.2);
  color: var(--text-primary);
  padding: 0.125em 0.25em;
  border-radius: var(--radius-xs);
}
code {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: var(--card-bg);
  border: 1px solid var(--border-primary);
  padding: 0.2em 0.4em;
  border-radius: var(--radius-sm, 0.25rem);
  color: var(--accent-primary);
  font-weight: var(--font-medium, 500);
}
kbd {
  font-family: var(--font-mono);
  font-size: 0.875em;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-secondary);
  padding: 0.2em 0.5em;
  border-radius: var(--radius-md, 0.5rem);
  box-shadow: 0 2px 0 var(--border-primary);
  font-weight: var(--font-semibold, 600);
}
pre {
  font-family: var(--font-mono);
  font-size: var(--text-sm, 0.875rem);
  background: var(--card-bg);
  border: 1px solid var(--border-primary);
  padding: var(--space-4, 1rem);
  border-radius: var(--radius-lg, 0.75rem);
  overflow-x: auto;
  margin: var(--space-6, 1.5rem) 0;
  line-height: var(--leading-relaxed);
}
pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: inherit;
}
blockquote {
  border-left: 4px solid var(--accent-primary);
  padding-left: var(--space-4, 1rem);
  margin: var(--space-6, 1.5rem) 0;
  font-style: italic;
  color: var(--text-secondary);
  font-size: var(--text-lg, 1.125rem);
}
blockquote cite {
  display: block;
  margin-top: var(--space-2, 0.5rem);
  font-size: var(--text-sm, 0.875rem);
  font-style: normal;
  color: var(--text-tertiary);
}
hr {
  border: none;
  border-top: 1px solid var(--border-primary);
  margin: var(--space-12, 3rem) 0;
}
a {
  color: var(--text-link);
  transition: color var(--transition-fast, 150ms);
  cursor: pointer;
}
a:hover {
  color: var(--text-link-hover);
}
a:focus-visible {
  outline: 2px solid var(--accent-primary);
  outline-offset: 2px;
  border-radius: var(--radius-xs);
}
.text-gradient {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.page-content-wrapper {
  flex: 1;
  display: flex;
  flex-direction: column;
  width: 100%;
  position: relative;
}
.container {
  width: 100%;
  max-width: var(--container-xl);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-6, 1.5rem);
  padding-right: var(--space-6, 1.5rem);
}
.container-xs { max-width: var(--container-xs); }
.container-sm { max-width: var(--container-sm); }
.container-md { max-width: var(--container-md); }
.container-lg { max-width: var(--container-lg); }
.container-xl { max-width: var(--container-xl); }
.container-2xl { max-width: var(--container-2xl); }
.container-full { max-width: var(--container-full); }
@media (max-width: 768px) {
  .container {
    padding-left: var(--space-4, 1rem);
    padding-right: var(--space-4, 1rem);
  }
}
.main-content, .main {
  width: 100%;
  max-width: var(--container-xl);
  margin: calc(var(--header-height) + var(--space-12)) auto var(--space-24, 6rem);
  padding: 0 var(--space-6, 1.5rem);
  margin-top: 0;
}
@media (max-width: 1024px) {
  .main-content, .main {
    margin-top: calc(var(--header-height) + var(--space-8));
    margin-bottom: var(--space-20, 5rem);
  }
}
@media (max-width: 768px) {
  .main-content, .main {
    margin-top: calc(var(--header-height) + var(--space-6));
    margin-bottom: var(--space-16, 4rem);
    padding: 0 var(--space-4, 1rem);
  }
}
section {
  padding: var(--space-20, 5rem) 0;
}
@media (max-width: 768px) {
  section {
    padding: var(--space-12, 3rem) 0;
  }
}
.grid {
  display: grid;
  gap: var(--space-6, 1.5rem);
}
.grid-cols-1 { grid-template-columns: repeat(1, minmax(0, 1fr)); }
.grid-cols-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-cols-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid-cols-5 { grid-template-columns: repeat(5, minmax(0, 1fr)); }
.grid-cols-6 { grid-template-columns: repeat(6, minmax(0, 1fr)); }
.grid-cols-12 { grid-template-columns: repeat(12, minmax(0, 1fr)); }
@media (max-width: 1024px) {
  .grid-cols-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid-cols-5 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .grid-cols-6 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}
@media (max-width: 768px) {
  .grid-cols-2,
  .grid-cols-3,
  .grid-cols-4,
  .grid-cols-5,
  .grid-cols-6 {
    grid-template-columns: repeat(1, minmax(0, 1fr));
  }
}
.grid-auto-fit {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(var(--testimonial-min-width), 1fr));
  gap: var(--space-6, 1.5rem);
}
@media (max-width: 768px) {
  .grid-auto-fit {
    grid-template-columns: 1fr;
    gap: var(--space-4, 1rem);
  }
}
.flex {
  display: flex;
}
.inline-flex {
  display: inline-flex;
}
.flex-row { flex-direction: row; }
.flex-col { flex-direction: column; }
.flex-row-reverse { flex-direction: row-reverse; }
.flex-col-reverse { flex-direction: column-reverse; }
.items-start { align-items: flex-start; }
.items-center { align-items: center; }
.items-end { align-items: flex-end; }
.items-baseline { align-items: baseline; }
.items-stretch { align-items: stretch; }
.justify-start { justify-content: flex-start; }
.justify-center { justify-content: center; }
.justify-end { justify-content: flex-end; }
.justify-between { justify-content: space-between; }
.justify-around { justify-content: space-around; }
.justify-evenly { justify-content: space-evenly; }
.flex-wrap { flex-wrap: wrap; }
.flex-nowrap { flex-wrap: nowrap; }
.flex-wrap-reverse { flex-wrap: wrap-reverse; }
.flex-1 { flex: 1 1 0%; }
.flex-auto { flex: 1 1 auto; }
.flex-initial { flex: 0 1 auto; }
.flex-none { flex: none; }
.gap-0 { gap: var(--space-0, 0); }
.gap-1 { gap: var(--space-1, 0.25rem); }
.gap-2 { gap: var(--space-2, 0.5rem); }
.gap-3 { gap: var(--space-3, 0.75rem); }
.gap-4 { gap: var(--space-4, 1rem); }
.gap-5 { gap: var(--space-5, 1.25rem); }
.gap-6 { gap: var(--space-6, 1.5rem); }
.gap-8 { gap: var(--space-8, 2rem); }
.gap-10 { gap: var(--space-10, 2.5rem); }
.gap-12 { gap: var(--space-12, 3rem); }
.hero-section {
  text-align: center;
  padding: var(--space-32, 8rem) 0 var(--space-24, 6rem);
  position: relative;
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: calc(100vh - var(--header-height));
}
@media (max-width: 1024px) {
  .hero-section {
    padding: var(--space-24, 6rem) 0 var(--space-20, 5rem);
    min-height: auto;
  }
}
@media (max-width: 768px) {
  .hero-section {
    padding: var(--space-20, 5rem) 0 var(--space-16, 4rem);
  }
}
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2, 0.5rem);
  padding: var(--space-2, 0.5rem) var(--space-4, 1rem);
  background: var(--card-bg);
  border: 1px solid var(--card-bg-border);
  border-radius: var(--radius-full, 9999px);
  font-size: var(--text-sm, 0.875rem);
  font-weight: var(--font-medium, 500);
  color: var(--text-secondary);
  margin-bottom: var(--space-6, 1.5rem);
  transition: all var(--transition-fast, 150ms);
  cursor: pointer;
}
.hero-badge:hover {
  border-color: var(--border-secondary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}
.badge-dot {
  width: 8px;
  height: 8px;
  background: var(--accent-secondary);
  border-radius: var(--radius-full, 9999px);
  animation: pulse-dot 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}
@keyframes pulse-dot {
  0%, 100% {
    opacity: 1;
    transform: scale(1);
  }
  50% {
    opacity: 0.5;
    transform: scale(1.1);
  }
}
.hero-title {
  font-size: clamp(2.5rem, 6vw, 5rem);
  font-weight: var(--font-extrabold, 800);
  line-height: 1.05;
  letter-spacing: var(--tracking-tighter);
  margin: 0 auto var(--space-6, 1.5rem);
  max-width: 1100px;
  background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-purple) 50%, var(--accent-pink) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.25rem);
  line-height: var(--leading-relaxed);
  color: var(--text-secondary);
  max-width: var(--duckai-card-max-width);
  margin: 0 auto var(--space-10, 2.5rem);
  font-weight: var(--font-normal, 400);
}
.hero-cta {
  display: flex;
  align-items: center;
  gap: var(--space-4, 1rem);
  justify-content: center;
  align-items: center;
  flex-wrap: wrap;
  margin-top: var(--space-2, 0.5rem);
}
@media (max-width: 640px) {
  .hero-cta {
    flex-direction: column;
    width: 100%;
    max-width: 400px;
    margin: var(--space-2, 0.5rem) auto 0;
  }
  .hero-cta .button,
  .hero-cta .cta-button {
    width: 100%;
    justify-content: center;
  }
}
.button,
.cta-button,
.cta-primary,
.cta-secondary,
button[class*="button"],
button[class*="cta"] {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2, 0.5rem);
  padding: var(--space-4, 1rem) var(--space-8, 2rem);
  border: 1px solid transparent;
  border-radius: var(--radius-lg, 0.75rem);
  font-family: var(--font-sans);
  font-size: var(--text-base, 1rem);
  font-weight: var(--font-semibold, 600);
  line-height: 1;
  text-align: center;
  white-space: nowrap;
  cursor: pointer;
  user-select: none;
  transition: all var(--transition-base, 250ms);
  text-decoration: none;
  position: relative;
  overflow: hidden;
}
.button:disabled,
.cta-button:disabled,
button:disabled {
  opacity: var(--opacity-50);
  cursor: not-allowed;
  pointer-events: none;
}
.button-xs {
  padding: var(--space-1-5, 0.375rem) var(--space-3, 0.75rem);
  font-size: var(--text-xs, 0.75rem);
}
.button-sm {
  padding: var(--space-2, 0.5rem) var(--space-4, 1rem);
  font-size: var(--text-sm, 0.875rem);
}
.button-md {
  padding: var(--space-3, 0.75rem) var(--space-6, 1.5rem);
  font-size: var(--text-base, 1rem);
}
.button-lg,
.cta-large {
  padding: var(--space-5, 1.25rem) var(--space-10, 2.5rem);
  font-size: var(--text-lg, 1.125rem);
}
.button-xl {
  padding: var(--space-6, 1.5rem) var(--space-12, 3rem);
  font-size: var(--text-xl, 1.25rem);
}
.button-primary,
.cta-primary {
  background: var(--accent-primary);
  color: var(--text-inverse);
  border-color: var(--accent-primary);
  box-shadow: var(--shadow-sm);
}
.button-primary:hover,
.cta-primary:hover {
  background: var(--accent-primary-hover);
  border-color: var(--accent-primary-hover);
  box-shadow: var(--shadow-colored);
  transform: translateY(-2px);
}
.button-primary:active,
.cta-primary:active {
  transform: translateY(0);
  box-shadow: var(--shadow-sm);
}
.button-secondary,
.cta-secondary {
  background: var(--card-bg);
  color: var(--text-primary);
  border-color: var(--border-primary);
  box-shadow: var(--shadow-sm);
}
.button-secondary:hover,
.cta-secondary:hover {
  background: var(--card-bg-hover);
  border-color: var(--border-secondary);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}
.button-secondary:active,
.cta-secondary:active {
  transform: translateY(0);
}
.button-ghost {
  background: transparent;
  color: var(--text-primary);
  border-color: transparent;
}
.button-ghost:hover {
  background: var(--card-bg);
  border-color: var(--border-primary);
}
.button-outline {
  background: transparent;
  color: var(--accent-primary);
  border-color: var(--accent-primary);
}
.button-outline:hover {
  background: var(--accent-primary-light);
  border-color: var(--accent-primary-hover);
  color: var(--accent-primary-hover);
}
.button-danger {
  background: var(--error);
  color: var(--text-inverse);
  border-color: var(--error);
}
.button-danger:hover {
  background: var(--error-hover);
  border-color: var(--error-hover);
  transform: translateY(-2px);
}
.button-success {
  background: var(--success);
  color: var(--text-inverse);
  border-color: var(--success);
}
.button-success:hover {
  background: var(--success-hover);
  border-color: var(--success-hover);
  transform: translateY(-2px);
}
.button-icon {
  padding: var(--space-3, 0.75rem);
  width: 44px;
  height: 44px;
  justify-content: center;
}
.button-icon.button-sm {
  padding: var(--space-2, 0.5rem);
  width: 36px;
  height: 36px;
}
.button-icon.button-lg {
  padding: var(--space-4, 1rem);
  width: 52px;
  height: 52px;
}
.cta-arrow {
  display: inline-flex;
  transition: transform var(--transition-fast, 150ms);
}
.button:hover .cta-arrow,
.cta-button:hover .cta-arrow {
  transform: translateX(4px);
}
.button-group {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2, 0.5rem);
  flex-wrap: wrap;
}
.button-full {
  width: 100%;
  justify-content: center;
}
.button-loading {
  position: relative;
  color: transparent;
  pointer-events: none;
}
.button-loading::after {
  content: '';
  position: absolute;
  width: 16px;
  height: 16px;
  border: 2px solid currentColor;
  border-right-color: transparent;
  border-radius: var(--radius-full, 9999px);
  animation: spin 0.6s linear infinite;
  color: var(--text-inverse);
}
@keyframes spin {
  to { transform: rotate(360deg); }
}
.card,
.stat-card,
.feature-card,
.step-card,
.benefit-card,
.testimonial-card {
  border: 1px solid var(--card-bg-border);
  border-radius: var(--radius-xl, 1rem);
  padding: var(--space-8, 2rem);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base, 250ms);
  position: relative;
}
.card:hover,
.stat-card:hover,
.feature-card:hover,
.step-card:hover,
.benefit-card:hover,
.testimonial-card:hover {
  background: var(--card-bg-hover);
  border-color: var(--border-secondary);
  box-shadow: var(--shadow-lg);
  transform: translateY(var(--translateY-hover));
}
.card-flat {
  box-shadow: none;
  border: none;
}
.card-elevated {
  box-shadow: var(--shadow-lg);
}
.card-elevated:hover {
  box-shadow: var(--shadow-xl);
}
.card-header {
  margin-bottom: var(--space-6, 1.5rem);
  padding-bottom: var(--space-4, 1rem);
  border-bottom: 1px solid var(--border-primary);
}
.card-body {
  margin-bottom: var(--space-6, 1.5rem);
}
.card-footer {
  margin-top: var(--space-6, 1.5rem);
  padding-top: var(--space-4, 1rem);
  border-top: 1px solid var(--border-primary);
}
.features-section {
  padding: var(--space-24, 6rem) 0;
  width: 100%;
}
@media (max-width: 768px) {
  .features-section {
    padding: var(--space-16, 4rem) 0;
  }
}
.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: var(--space-6, 1.5rem);
  margin-top: var(--space-12, 3rem);
}
@media (max-width: 768px) {
  .features {
    grid-template-columns: 1fr;
    gap: var(--space-4, 1rem);
  }
}
.feature-card {
  display: flex;
  flex-direction: column;
  text-align: left;
  position: relative;
}
.feature-icon {
  width: var(--chatbot-btn-size);
  height: var(--chatbot-btn-size);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-primary-hover));
  border-radius: var(--radius-lg, 0.75rem);
  color: white;
  font-size: 24px;
  margin-bottom: var(--space-4, 1rem);
  transition: transform var(--transition-base, 250ms);
  flex-shrink: 0;
}
.feature-card:hover .feature-icon {
  transform: scale(var(--scale-hover)) rotate(var(--rotate-hover));
}
.feature-card h3 {
  font-size: var(--text-xl, 1.25rem);
  font-weight: var(--font-semibold, 600);
  margin-bottom: var(--space-3, 0.75rem);
  color: var(--text-primary);
}
.feature-card p {
  font-size: var(--text-base, 1rem);
  line-height: var(--leading-relaxed);
  color: var(--text-secondary);
  margin: 0;
  flex-grow: 1;
}
.feature-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2, 0.5rem);
  margin-top: var(--space-4, 1rem);
  border-radius: 25px;
  background-color: var(--card-bg);
  opacity: 0.8;
}
.tag {
  display: inline-flex;
  align-items: center;
  padding: var(--space-1, 0.25rem) var(--space-3, 0.75rem);
  background: var(--card-bg);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-full, 9999px);
  font-size: var(--text-xs, 0.75rem);
  font-weight: var(--font-medium, 500);
  color: var(--text-secondary);
  transition: all var(--transition-fast, 150ms);
  cursor: pointer;
}
.tag:hover {
  border-color: var(--accent-primary);
  color: var(--accent-primary);
  transform: translateY(-2px);
}
.tag-primary {
  background: var(--accent-primary-light);
  border-color: var(--accent-primary);
  color: var(--accent-primary);
}
.tag-success {
  background: var(--success-light);
  border-color: var(--success);
  color: var(--success);
}
.stats-section {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-8, 2rem);
  padding: var(--space-24, 6rem) 0;
}
@media (max-width: 768px) {
  .stats-section {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-6, 1.5rem);
    padding: var(--space-16, 4rem) 0;
  }
}
.stat-card {
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--space-8, 2rem);
}
.stat-number {
  font-size: clamp(2.5rem, 5vw, 4rem);
  font-weight: var(--font-extrabold, 800);
  line-height: 1;
  color: var(--accent-primary);
  margin-bottom: var(--space-3, 0.75rem);
  font-variant-numeric: tabular-nums;
}
.stat-label {
  font-size: var(--text-sm, 0.875rem);
  font-weight: var(--font-medium, 500);
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: var(--tracking-wide);
}
.form-group {
  margin-bottom: var(--space-6, 1.5rem);
}
.form-label {
  display: block;
  font-size: var(--text-sm, 0.875rem);
  font-weight: var(--font-medium, 500);
  color: var(--text-primary);
  margin-bottom: var(--space-2, 0.5rem);
}
.form-label-required::after {
  content: '*';
  color: var(--error);
  margin-left: var(--space-1, 0.25rem);
}
.form-hint {
  display: block;
  font-size: var(--text-xs, 0.75rem);
  color: var(--text-tertiary);
  margin-top: var(--space-2, 0.5rem);
}
.form-error {
  display: block;
  font-size: var(--text-xs, 0.75rem);
  color: var(--error);
  margin-top: var(--space-2, 0.5rem);
}
.textInput,
input[type="text"],
input[type="email"],
input[type="password"],
input[type="number"],
input[type="tel"],
input[type="url"],
input[type="search"],
input#username,
input#username-email,
input#studyGoal,
input#delete-confirm-text, 
textarea {
  width: 100%;
  padding: var(--space-4, 1rem);
  background: var(--card-bg);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-lg, 0.75rem);
  font-family: var(--font-sans);
  font-size: var(--text-base, 1rem);
  color: var(--text-primary);
  transition: all var(--transition-fast, 150ms);
  outline: none;
}
.textInput:hover,
input:hover,
textarea:hover {
  border-color: var(--border-secondary);
}
.textInput:focus,
input:focus,
textarea:focus {
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 4px rgba(67, 83, 255, 0.1);
  background: var(--bg-elevated);
}
textarea {
  min-height: 120px;
  resize: vertical;
}
select {
  width: 100%;
  padding: var(--space-4, 1rem);
  background: var(--card-bg);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-lg, 0.75rem);
  font-family: var(--font-sans);
  font-size: var(--text-base, 1rem);
  color: var(--text-primary);
  cursor: pointer;
  transition: all var(--transition-fast, 150ms);
  outline: none;
}
select:hover {
  border-color: var(--border-secondary);
}
select:focus {
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 4px rgba(67, 83, 255, 0.1);
}
input[type="checkbox"],
input[type="radio"] {
  appearance: none;
  width: var(--donate-icon-size);
  height: var(--donate-icon-size);
  border: 2px solid var(--border-primary);
  background: var(--card-bg);
  cursor: pointer;
  transition: all var(--transition-fast, 150ms);
  flex-shrink: 0;
  margin: 0;
}
input[type="checkbox"] {
  border-radius: var(--radius-sm, 0.25rem);
}
input[type="radio"] {
  border-radius: var(--radius-full, 9999px);
}
input[type="checkbox"]:checked,
input[type="radio"]:checked {
  background: var(--accent-primary);
  border-color: var(--accent-primary);
}
input[type="checkbox"]:checked::after {
  content: '✓';
  position: absolute;
  color: white;
  font-size: 14px;
  font-weight: var(--font-bold, 700);
}
nav,
.navbar {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(var(--blur-lg));
  -webkit-backdrop-filter: blur(var(--blur-lg));
  border-bottom: 1px solid var(--border-primary);
  height: var(--navbar-height);
  transition: all var(--transition-base, 250ms);
}
[data-theme="dark"] nav,
[data-theme="dark"] .navbar,
body.dark nav,
body.dark .navbar {
  background: rgba(10, 10, 10, 0.8);
}
.nav-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: var(--container-2xl);
  margin: 0 auto;
  padding: 0 var(--space-6, 1.5rem);
}
.nav-logo {
  font-size: var(--text-xl, 1.25rem);
  font-weight: var(--font-bold, 700);
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: var(--space-2, 0.5rem);
}
.nav-links {
  display: flex;
  gap: var(--space-8, 2rem);
  align-items: center;
}
.nav-links a {
  color: var(--text-secondary);
  font-size: var(--text-sm, 0.875rem);
  font-weight: var(--font-medium, 500);
  transition: color var(--transition-fast, 150ms);
  position: relative;
}
.nav-links a:hover {
  color: var(--text-primary);
}
.nav-links a.active {
  color: var(--accent-primary);
}
footer {
  margin-top: auto;
  padding: var(--space-20, 5rem) 0 var(--space-12, 3rem);
  background: var(--card-bg);
  border-top: 1px solid var(--border-primary);
  width: 100%;
  text-align: center;
}
footer p {
  font-size: var(--text-sm, 0.875rem);
  color: var(--text-tertiary);
  margin-bottom: var(--space-2, 0.5rem);
}
.repoLink {
  color: var(--accent-primary);
  font-weight: var(--font-medium, 500);
  transition: color var(--transition-fast, 150ms);
}
.repoLink:hover {
  color: var(--accent-primary-hover);
}
.alert {
  padding: var(--space-4, 1rem);
  border-radius: var(--radius-lg, 0.75rem);
  border: 1px solid;
  margin-bottom: var(--space-4, 1rem);
  display: flex;
  align-items: flex-start;
  gap: var(--space-3, 0.75rem);
}
.alert-info {
  background: var(--info-light);
  border-color: var(--info-border);
  color: var(--info);
}
.alert-success {
  background: var(--success-light);
  border-color: var(--success-border);
  color: var(--success);
}
.alert-warning {
  background: var(--warning-light);
  border-color: var(--warning-border);
  color: var(--warning);
}
.alert-error {
  background: var(--error-light);
  border-color: var(--error-border);
  color: var(--error);
}
.badge {
  display: inline-flex;
  align-items: center;
  padding: var(--space-1, 0.25rem) var(--space-2, 0.5rem);
  border-radius: var(--radius-sm, 0.25rem);
  font-size: var(--text-xs, 0.75rem);
  font-weight: var(--font-semibold, 600);
  line-height: 1;
}
.badge-primary {
  background: var(--accent-primary);
  color: var(--text-inverse);
}
.badge-secondary {
  background: var(--bg-tertiary);
  color: var(--text-secondary);
}
.badge-success {
  background: var(--success);
  color: white;
}
.badge-error {
  background: var(--error);
  color: white;
}
.modal-overlay {
  position: fixed;
  inset: 0;
  background: var(--bg-overlay);
  backdrop-filter: blur(var(--blur-sm));
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--z-modal-backdrop);
  padding: var(--space-4, 1rem);
}
.modal {
  background: var(--card-bg);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-2xl, 1.5rem);
  box-shadow: var(--shadow-2xl);
  max-width: 640px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  z-index: var(--z-modal);
}
.modal-header {
  padding: var(--space-6, 1.5rem);
  border-bottom: 1px solid var(--border-primary);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.modal-title {
  font-size: var(--text-xl, 1.25rem);
  font-weight: var(--font-semibold, 600);
  margin: 0;
}
.modal-body {
  padding: var(--space-6, 1.5rem);
}
.modal-footer {
  padding: var(--space-6, 1.5rem);
  border-top: 1px solid var(--border-primary);
  display: flex;
  justify-content: flex-end;
  gap: var(--space-3, 0.75rem);
}
.dropdown {
  position: relative;
  display: inline-block;
}
.dropdown-menu {
  position: absolute;
  top: calc(100% + var(--space-2));
  left: 0;
  min-width: var(--button-min-width-large);
  background: var(--card-bg);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-lg, 0.75rem);
  box-shadow: var(--shadow-xl);
  padding: var(--space-2, 0.5rem);
  z-index: var(--z-dropdown);
  opacity: 0;
  pointer-events: none;
  transform: translateY(-8px);
  transition: all var(--transition-fast, 150ms);
}
.dropdown.open .dropdown-menu {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}
.dropdown-item {
  padding: var(--space-2, 0.5rem) var(--space-3, 0.75rem);
  border-radius: var(--radius-md, 0.5rem);
  cursor: pointer;
  transition: background var(--transition-fast, 150ms);
  display: flex;
  align-items: center;
  gap: var(--space-2, 0.5rem);
  font-size: var(--text-sm, 0.875rem);
}
.dropdown-item:hover {
  background: var(--bg-tertiary);
}
.tabs {
  display: flex;
  flex-direction: column;
  gap: var(--space-4, 1rem);
}
.tab-list {
  display: flex;
  gap: var(--space-2, 0.5rem);
  border-bottom: 1px solid var(--border-primary);
}
.tab-button {
  padding: var(--space-3, 0.75rem) var(--space-4, 1rem);
  border: none;
  background: none;
  color: var(--text-secondary);
  font-weight: var(--font-medium, 500);
  cursor: pointer;
  position: relative;
  transition: color var(--transition-fast, 150ms);
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
}
.tab-button:hover {
  color: var(--text-primary);
}
.tab-button.active {
  color: var(--accent-primary);
  border-bottom-color: var(--accent-primary);
}
.accordion {
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-lg, 0.75rem);
  overflow: hidden;
}
.accordion-item {
  border-bottom: 1px solid var(--border-primary);
}
.accordion-item:last-child {
  border-bottom: none;
}
.accordion-header {
  padding: var(--space-4, 1rem);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--card-bg);
  transition: background var(--transition-fast, 150ms);
  font-weight: var(--font-medium, 500);
}
.accordion-header:hover {
  background: var(--card-bg-hover);
}
.progress {
  width: 100%;
  height: 8px;
  background: var(--bg-tertiary);
  border-radius: var(--radius-full, 9999px);
  overflow: hidden;
}
.progress-bar {
  height: 100%;
  background: var(--accent-primary);
  border-radius: var(--radius-full, 9999px);
  transition: width var(--transition-slow, 350ms);
}
.spinner {
  width: 24px;
  height: 24px;
  border: 3px solid var(--border-primary);
  border-top-color: var(--accent-primary);
  border-radius: var(--radius-full, 9999px);
  animation: spin 0.6s linear infinite;
}

body.dark .spinner {
    border-top-color: #4dabf7;
}
.spinner-sm {
  width: var(--donate-icon-size);
  height: var(--donate-icon-size);
  border-width: 2px;
}
.spinner-lg {
  width: 60px;
  height: 60px;
  border-width: 4px;
}
.avatar {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full, 9999px);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--accent-primary);
  color: white;
  font-weight: var(--font-semibold, 600);
}
.avatar-sm {
  width: var(--user-avatar-size);
  height: var(--user-avatar-size);
  font-size: var(--text-sm, 0.875rem);
}
.avatar-lg {
  width: 56px;
  height: 56px;
  font-size: var(--text-xl, 1.25rem);
}
.avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.table {
  width: 100%;
  background: var(--card-bg);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-lg, 0.75rem);
  overflow: hidden;
}
.table thead {
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-primary);
}
.table th {
  padding: var(--space-3, 0.75rem) var(--space-4, 1rem);
  text-align: left;
  font-weight: var(--font-semibold, 600);
  font-size: var(--text-sm, 0.875rem);
  color: var(--text-secondary);
  text-transform: uppercase;
}
.table td {
  padding: var(--space-3, 0.75rem) var(--space-4, 1rem);
  border-top: 1px solid var(--border-primary);
}
.table tbody tr:hover {
  background: var(--bg-secondary);
}
.pagination {
  display: flex;
  gap: var(--space-2, 0.5rem);
  align-items: center;
}
.pagination-item {
  min-width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 var(--space-3, 0.75rem);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-md, 0.5rem);
  background: var(--card-bg);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast, 150ms);
  font-weight: var(--font-medium, 500);
}
.pagination-item:hover {
  border-color: var(--accent-primary);
  color: var(--accent-primary);
}
.pagination-item.active {
  background: var(--accent-primary);
  border-color: var(--accent-primary);
  color: white;
}
.block { display: block; }
.inline-block { display: inline-block; }
.inline { display: inline; }
.hidden { display: none; }
.relative { position: relative; }
.absolute { position: absolute; }
.fixed { position: fixed; }
.sticky { position: sticky; }
.overflow-hidden { overflow: hidden; }
.overflow-auto { overflow: auto; }
.overflow-scroll { overflow: scroll; }
.w-full { width: 100%; }
.w-auto { width: auto; }
.h-full { height: 100%; }
.h-auto { height: auto; }
.m-0 { margin: var(--space-0, 0); }
.m-auto { margin: auto; }
.m-1 { margin: var(--space-1, 0.25rem); }
.m-2 { margin: var(--space-2, 0.5rem); }
.m-3 { margin: var(--space-3, 0.75rem); }
.m-4 { margin: var(--space-4, 1rem); }
.m-6 { margin: var(--space-6, 1.5rem); }
.m-8 { margin: var(--space-8, 2rem); }
.mx-auto { margin-left: auto; margin-right: auto; }
.my-0 { margin-top: var(--space-0, 0); margin-bottom: var(--space-0, 0); }
.my-2 { margin-top: var(--space-2, 0.5rem); margin-bottom: var(--space-2, 0.5rem); }
.my-4 { margin-top: var(--space-4, 1rem); margin-bottom: var(--space-4, 1rem); }
.my-6 { margin-top: var(--space-6, 1.5rem); margin-bottom: var(--space-6, 1.5rem); }
.my-8 { margin-top: var(--space-8, 2rem); margin-bottom: var(--space-8, 2rem); }
.mt-0 { margin-top: var(--space-0, 0); }
.mt-2 { margin-top: var(--space-2, 0.5rem); }
.mt-4 { margin-top: var(--space-4, 1rem); }
.mt-6 { margin-top: var(--space-6, 1.5rem); }
.mt-8 { margin-top: var(--space-8, 2rem); }
.mt-12 { margin-top: var(--space-12, 3rem); }
.mb-0 { margin-bottom: var(--space-0, 0); }
.mb-2 { margin-bottom: var(--space-2, 0.5rem); }
.mb-4 { margin-bottom: var(--space-4, 1rem); }
.mb-6 { margin-bottom: var(--space-6, 1.5rem); }
.mb-8 { margin-bottom: var(--space-8, 2rem); }
.mb-12 { margin-bottom: var(--space-12, 3rem); }
.p-0 { padding: var(--space-0, 0); }
.p-2 { padding: var(--space-2, 0.5rem); }
.p-4 { padding: var(--space-4, 1rem); }
.p-6 { padding: var(--space-6, 1.5rem); }
.p-8 { padding: var(--space-8, 2rem); }
.px-2 { padding-left: var(--space-2, 0.5rem); padding-right: var(--space-2, 0.5rem); }
.px-4 { padding-left: var(--space-4, 1rem); padding-right: var(--space-4, 1rem); }
.px-6 { padding-left: var(--space-6, 1.5rem); padding-right: var(--space-6, 1.5rem); }
.px-8 { padding-left: var(--space-8, 2rem); padding-right: var(--space-8, 2rem); }
.py-2 { padding-top: var(--space-2, 0.5rem); padding-bottom: var(--space-2, 0.5rem); }
.py-4 { padding-top: var(--space-4, 1rem); padding-bottom: var(--space-4, 1rem); }
.py-6 { padding-top: var(--space-6, 1.5rem); padding-bottom: var(--space-6, 1.5rem); }
.py-8 { padding-top: var(--space-8, 2rem); padding-bottom: var(--space-8, 2rem); }
.text-left { text-align: left; }
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-xs { font-size: var(--text-xs, 0.75rem); }
.text-sm { font-size: var(--text-sm, 0.875rem); }
.text-base { font-size: var(--text-base, 1rem); }
.text-lg { font-size: var(--text-lg, 1.125rem); }
.text-xl { font-size: var(--text-xl, 1.25rem); }
.text-2xl { font-size: var(--text-2xl, 1.5rem); }
.text-3xl { font-size: var(--text-3xl, 1.875rem); }
.font-light { font-weight: var(--font-light); }
.font-normal { font-weight: var(--font-normal, 400); }
.font-medium { font-weight: var(--font-medium, 500); }
.font-semibold { font-weight: var(--font-semibold, 600); }
.font-bold { font-weight: var(--font-bold, 700); }
.font-extrabold { font-weight: var(--font-extrabold, 800); }
.text-primary { color: var(--text-primary); }
.text-secondary { color: var(--text-secondary); }
.text-tertiary { color: var(--text-tertiary); }
.text-accent { color: var(--accent-primary); }
.text-success { color: var(--success); }
.text-error { color: var(--error); }
.text-warning { color: var(--warning); }
.bg-primary { background-color: var(--bg-primary); }
.bg-secondary { background-color: var(--bg-secondary); }
.bg-tertiary { background-color: var(--bg-tertiary); }
.bg-card { background-color: var(--card-bg); }
.bg-accent { background-color: var(--accent-primary); }
.rounded-none { border-radius: var(--radius-none); }
.rounded-sm { border-radius: var(--radius-sm, 0.25rem); }
.rounded { border-radius: var(--radius-md, 0.5rem); }
.rounded-lg { border-radius: var(--radius-lg, 0.75rem); }
.rounded-xl { border-radius: var(--radius-xl, 1rem); }
.rounded-2xl { border-radius: var(--radius-2xl, 1.5rem); }
.rounded-full { border-radius: var(--radius-full, 9999px); }
.border { border: 1px solid var(--border-primary); }
.border-0 { border: 0; }
.border-2 { border: 2px solid var(--border-primary); }
.shadow-none { box-shadow: none; }
.shadow-xs { box-shadow: var(--shadow-xs); }
.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow-md { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }
.shadow-xl { box-shadow: var(--shadow-xl); }
.opacity-0 { opacity: var(--opacity-0); }
.opacity-25 { opacity: var(--opacity-25); }
.opacity-50 { opacity: var(--opacity-50); }
.opacity-75 { opacity: var(--opacity-75); }
.opacity-100 { opacity: var(--opacity-100); }
.cursor-pointer { cursor: pointer; }
.cursor-not-allowed { cursor: not-allowed; }
.select-none { user-select: none; }
.pointer-events-none { pointer-events: none; }
.pointer-events-auto { pointer-events: auto; }
.transition-none { transition: none; }
.transition-all { transition: all var(--transition-base, 250ms); }
.transition-fast { transition: all var(--transition-fast, 150ms); }
.transition-slow { transition: all var(--transition-slow, 350ms); }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}
:focus {
  outline: none;
}
:focus-visible {
  outline: 2px solid var(--accent-primary);
  outline-offset: 2px;
  border-radius: var(--radius-sm, 0.25rem);
}
::selection {
  background: rgba(67, 83, 255, 0.2);
  color: var(--text-primary);
}
::-webkit-scrollbar {
  width: 12px;
  height: 12px;
}
::-webkit-scrollbar-track {
  background: var(--bg-secondary);
}
::-webkit-scrollbar-thumb {
  background: var(--border-secondary);
  border-radius: var(--radius-lg, 0.75rem);
  border: 3px solid var(--bg-secondary);
  transition: background var(--transition-fast, 150ms);
}
::-webkit-scrollbar-thumb:hover {
  background: var(--accent-primary);
}
@media (max-width: 1024px) {
  .md\:hidden { display: none; }
  .md\:block { display: block; }
  .md\:flex { display: flex; }
  .md\:grid-cols-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 768px) {
  html { font-size: 14px; }
  .sm\:hidden { display: none; }
  .sm\:block { display: block; }
  .sm\:flex { display: flex; }
  .sm\:flex-col { flex-direction: column; }
  .sm\:text-center { text-align: center; }
  .sm\:grid-cols-1 { grid-template-columns: 1fr; }
}
[data-theme="dark"] .dark\:block,
body.dark .dark\:block { display: block; }
[data-theme="dark"] .dark\:hidden,
body.dark .dark\:hidden { display: none; }
.light\:block { display: block; }
.dark\:block { display: none; }
[data-theme="dark"] .light\:block,
body.dark .light\:block { display: none; }
[data-theme="dark"] .dark\:block,
body.dark .dark\:block { display: block; }
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}
.main-content {
    max-width: 1200px;
    width: 90%;
    margin: 140px auto 90px;
    padding: 48px 40px 80px;
    text-align: center;
    background: var(--card-bg);
    backdrop-filter: blur(20px) saturate(180%);
    border-radius: 2rem;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--card-bg-border);
    transition: all 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    position: relative;
}
.main-content::before {
    content: '';
    position: absolute;
    inset: -2px;
    border-radius: 2rem;
    background: linear-gradient(135deg, rgba(67, 83, 255, 0.1), rgba(236, 72, 153, 0.05));
    opacity: 0;
    transition: opacity 0.4s ease;
    z-index: -1;
    pointer-events: none;
}
.main-content:hover::before {
    opacity: 1;
}
.main-content h2 {
    font-size: 3rem;
    margin-bottom: 1.8rem;
    color: var(--text-primary);
    font-weight: 800;
    letter-spacing: -0.02em;
}
.main-content p {
    font-size: 1.2rem;
    margin-bottom: 2.5rem;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
    color: var(--text-secondary);
    line-height: 1.8;
}
.main {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 2rem;
    width: 100%;
}
.selectors {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    max-width: 700px;
    width: 100%;
    margin: 0 auto;
}
.selector-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    text-align: center;
}
.selector-group label,
.checkbox {
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
    text-align: center;
}
.selector-group select,
.selector-group input[type="number"],
.select {
    width: 100%;
    padding: 1rem 1.25rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-primary);
    border-radius: 0.75rem;
    color: var(--text-primary);
    font-size: 1rem;
    font-family: inherit;
    transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    outline: none;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}
.selector-group select:focus,
.selector-group input[type="number"]:focus,
.select:focus {
    background: var(--bg-primary);
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 4px rgba(67, 83, 255, 0.1), 0 4px 12px rgba(0, 0, 0, 0.08);
    transform: translateY(-2px);
}
.selector-group select:hover,
.selector-group input[type="number"]:hover,
.select:hover {
    border-color: var(--border-secondary);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
}
.file-upload-section {
    margin: 0 auto;
    max-width: 700px;
    width: 100%;
}
.file-upload-wrapper {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    padding: 3rem;
    border: 2px dashed var(--border-primary);
    border-radius: 1.5rem;
    background: var(--card-bg);
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    cursor: pointer;
}
.file-upload-wrapper:hover {
    border-color: var(--accent-primary);
    background: var(--card-bg-hover);
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(67, 83, 255, 0.15);
}
.file-upload-wrapper.drag-over {
    border-color: var(--accent-primary);
    background: rgba(67, 83, 255, 0.05);
    transform: scale(1.02);
    box-shadow: 0 0 0 4px rgba(67, 83, 255, 0.1);
}
.upload-icon {
    font-size: 3.5rem;
    color: var(--accent-primary);
    opacity: 0.6;
    transition: all 0.3s ease;
}
.file-upload-wrapper:hover .upload-icon {
    opacity: 1;
    transform: scale(1.1);
}
.upload-text {
    text-align: center;
}
.upload-text p {
    margin: 0;
    color: var(--text-secondary);
}
.upload-text .primary {
    font-weight: 600;
    color: var(--text-primary);
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}
.upload-text .secondary {
    font-size: 0.9rem;
    color: var(--text-tertiary);
}
input[type="file"],
.file-input {
    display: none;
}
.file-name {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.875rem 1.5rem;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-primary);
    border-radius: 0.75rem;
    font-size: 0.95rem;
    color: var(--text-primary);
    max-width: 100%;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}
.file-icon {
    color: var(--accent-primary);
    font-size: 1.2rem;
}
.fileButton {
    padding: 0.875rem 1.75rem;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-pink));
    color: white;
    border: none;
    border-radius: 0.75rem;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    box-shadow: 0 8px 24px rgba(67, 83, 255, 0.3);
}
.fileButton:hover {
    transform: translateY(-2px) scale(1.02);
    box-shadow: 0 12px 32px rgba(67, 83, 255, 0.4);
}
.fileButton:active {
    transform: translateY(0) scale(1);
}
.quiz-card,
.note-card,
.analysis-card {
    background: var(--card-bg);
    backdrop-filter: blur(20px) saturate(180%);
    border: 1px solid var(--card-bg-border);
    border-radius: 1.5rem;
    padding: 2.5rem;
    margin-bottom: 2rem;
    transition: all 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
    text-align: left;
}
.quiz-card:hover,
.note-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 12px 32px rgba(67, 83, 255, 0.15);
    border-color: var(--accent-primary);
}
.question-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    gap: 1rem;
}
.question-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 3rem;
    height: 3rem;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-pink));
    color: white;
    border-radius: 50%;
    font-weight: 800;
    font-size: 1.25rem;
    box-shadow: 0 4px 16px rgba(67, 83, 255, 0.3);
}
.difficulty-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    border-radius: 9999px;
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: capitalize;
    transition: all 0.2s ease;
}
.difficulty-badge.easy {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
    border: 1px solid rgba(16, 185, 129, 0.3);
}
.difficulty-badge.medium {
    background: rgba(245, 158, 11, 0.1);
    color: var(--warning);
    border: 1px solid rgba(245, 158, 11, 0.3);
}
.difficulty-badge.hard {
    background: rgba(239, 68, 68, 0.1);
    color: var(--error);
    border: 1px solid rgba(239, 68, 68, 0.3);
}
.question-text {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 2rem;
    line-height: 1.7;
}
.options-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}
.option-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    padding: 1.25rem 1.5rem;
    background: var(--bg-secondary);
    border: 2px solid var(--border-primary);
    border-radius: 1rem;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    position: relative;
}
.option-item:hover {
    background: var(--bg-tertiary);
    border-color: var(--accent-primary);
    transform: translateX(6px);
    box-shadow: 0 4px 16px rgba(67, 83, 255, 0.1);
}
.option-item input[type="radio"] {
    width: 1.5rem;
    height: 1.5rem;
    margin-top: 0.125rem;
    cursor: pointer;
    flex-shrink: 0;
    accent-color: var(--accent-primary);
}
.option-label {
    flex: 1;
    cursor: pointer;
    font-size: 1.05rem;
    color: var(--text-primary);
    line-height: 1.6;
}
.option-item.selected {
    background: rgba(67, 83, 255, 0.1);
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 4px rgba(67, 83, 255, 0.1);
}
.option-item.correct {
    background: rgba(16, 185, 129, 0.1);
    border-color: var(--success);
    box-shadow: 0 0 0 4px rgba(16, 185, 129, 0.1);
}
.option-item.incorrect {
    background: rgba(239, 68, 68, 0.1);
    border-color: var(--error);
    box-shadow: 0 0 0 4px rgba(239, 68, 68, 0.1);
}
.option-marker {
    position: absolute;
    right: 1.5rem;
    top: 50%;
    transform: translateY(-50%);
    font-size: 1.5rem;
    font-weight: 700;
}
.option-item.correct .option-marker {
    color: var(--success);
}
.option-item.incorrect .option-marker {
    color: var(--error);
}
.quiz-actions {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-top: 3rem;
    flex-wrap: wrap;
}
.button,
.submit {
    padding: 1rem 2rem;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-pink));
    color: white;
    border: none;
    border-radius: 0.75rem;
    font-size: 1.05rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    box-shadow: 0 8px 24px rgba(67, 83, 255, 0.3);
    position: relative;
    overflow: hidden;
}
.button::before,
.submit::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transform: translate(-50%, -50%);
    transition: width 0.6s ease, height 0.6s ease;
}
.button:active::before,
.submit:active::before {
    width: 300px;
    height: 300px;
}
.button:hover,
.submit:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 12px 32px rgba(67, 83, 255, 0.4);
}
.button:active,
.submit:active {
    transform: translateY(0) scale(1);
}
.button:disabled,
.submit:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}
.score-display {
    text-align: center;
    padding: 4rem 2rem;
    background: var(--card-bg);
    backdrop-filter: blur(20px) saturate(180%);
    border: 1px solid var(--card-bg-border);
    border-radius: 2rem;
    margin-bottom: 3rem;
    box-shadow: var(--shadow-lg);
    color: var(--text-primary) !important;
}
.score-circle {
    width: 200px;
    height: 200px;
    margin: 0 auto 2rem;
    border-radius: 50%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(67, 83, 255, 0.1), rgba(236, 72, 153, 0.1));
    border: 4px solid var(--accent-primary);
    box-shadow: 0 8px 32px rgba(67, 83, 255, 0.2);
    transition: all 0.3s ease;
}
.score-circle:hover {
    transform: scale(1.05);
    box-shadow: 0 12px 48px rgba(67, 83, 255, 0.3);
}
.score-percentage {
    font-size: 3.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-pink));
    -webkit-background-clip: text;
    background-clip: text;
}
.score-label {
    font-size: 1rem;
    color: var(--text-tertiary);
    margin-top: 0.5rem;
    font-weight: 600;
}
.score-details {
    display: flex;
    justify-content: center;
    gap: 3rem;
    margin-top: 2rem;
    flex-wrap: wrap;
}
.score-stat {
    text-align: center;
}
.score-stat-value {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text-primary);
}
.score-stat-label {
    font-size: 1rem;
    color: var(--text-tertiary);
    margin-top: 0.5rem;
    font-weight: 500;
}
.score-excellent { border-color: var(--success) !important; }
.score-good { border-color: var(--info) !important; }
.score-needs-work { border-color: var(--warning) !important; }
.score-poor { border-color: var(--error) !important; }
.nav-button {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 3.5rem;
    height: 3.5rem;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-pink));
    color: white;
    border: none;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    font-size: 1.5rem;
    box-shadow: 0 4px 16px rgba(67, 83, 255, 0.3);
}
.nav-button:hover {
    transform: scale(1.15);
    box-shadow: 0 8px 24px rgba(67, 83, 255, 0.4);
}
.nav-button:disabled {
    opacity: 0.3;
    cursor: not-allowed;
    transform: none;
}
.analysis-section {
    margin-bottom: 3rem;
    text-align: left;
}
.section-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 2rem;
    display: flex;
    align-items: center;
    gap: 1rem;
}
.section-icon {
    font-size: 2rem;
}
.insight-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
}
.insight-card {
    padding: 2rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-primary);
    border-radius: 1.25rem;
    transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}
.insight-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(67, 83, 255, 0.1);
    border-color: var(--accent-primary);
}
.insight-label {
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-tertiary);
    margin-bottom: 0.75rem;
}
.insight-value {
    font-size: 2rem;
    font-weight: 800;
    color: var(--text-primary);
}
.confidence-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.625rem 1.25rem;
    border-radius: 9999px;
    font-size: 0.875rem;
    font-weight: 600;
}
.confidence-high {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
    border: 1px solid rgba(16, 185, 129, 0.3);
}
.confidence-medium {
    background: rgba(245, 158, 11, 0.1);
    color: var(--warning);
    border: 1px solid rgba(245, 158, 11, 0.3);
}
.confidence-low {
    background: rgba(239, 68, 68, 0.1);
    color: var(--error);
    border: 1px solid rgba(239, 68, 68, 0.3);
}
.suggestion-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}
.suggestion-item {
    padding: 1.5rem;
    background: var(--bg-secondary);
    border-left: 4px solid var(--accent-primary);
    border-radius: 1rem;
    transition: all 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}
.suggestion-item:hover {
    background: var(--bg-tertiary);
    transform: translateX(6px);
    box-shadow: 0 4px 16px rgba(67, 83, 255, 0.1);
}
.suggestion-item p {
    margin: 0;
    color: var(--text-primary);
    line-height: 1.7;
    font-size: 1.05rem;
}
.enhanced-note-section {
    margin-bottom: 2.5rem;
    text-align: left;
}
.enhanced-note-section h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1.25rem;
}
.enhanced-note-section ul,
.enhanced-note-section ol {
    margin: 1rem 0;
    padding-left: 2rem;
}
.enhanced-note-section li {
    margin-bottom: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.7;
    list-style: disc;
}
.enhanced-note-section ol li {
    list-style: decimal;
}
.enhanced-note-section p {
    margin-bottom: 1rem;
    line-height: 1.7;
    color: var(--text-secondary);
    font-size: 1.05rem;
}
.loading-spinner {
    display: inline-block;
    width: 2.5rem;
    height: 2.5rem;
    border: 3px solid var(--border-primary);
    border-top-color: var(--accent-primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}
@keyframes spin {
    to { transform: rotate(360deg); }
}
.status-message {
    padding: 1.25rem 1.75rem;
    border-radius: 1rem;
    margin-bottom: 2rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    font-weight: 600;
    font-size: 1.05rem;
}
.status-success {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
    border: 1px solid rgba(16, 185, 129, 0.3);
}
.status-error {
    background: rgba(239, 68, 68, 0.1);
    color: var(--error);
    border: 1px solid rgba(239, 68, 68, 0.3);
}
.status-info {
    background: rgba(59, 130, 246, 0.1);
    color: var(--info);
    border: 1px solid rgba(59, 130, 246, 0.3);
}
.textInput {
    width: 100%;
    padding: 1.25rem;
    border: 1px solid var(--border-primary);
    border-radius: 1rem;
    font-family: inherit;
    min-height: 100px;
    resize: vertical;
    font-size: 1rem;
    background: var(--bg-secondary);
    backdrop-filter: blur(20px) saturate(180%);
    transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
    color: var(--text-primary);
    outline: none;
    text-align: left;
}
.textInput:focus {
    border-color: var(--accent-primary);
    background: var(--bg-primary);
    box-shadow: 0 0 0 4px rgba(67, 83, 255, 0.1), 0 4px 12px rgba(0, 0, 0, 0.08);
    transform: translateY(-2px);
}
.textInput::placeholder {
    color: var(--text-tertiary);
    transition: all 0.3s ease;
}
.textInput:focus::placeholder {
    color: var(--text-quaternary);
    transform: translateX(4px);
}
.chatbot-messages {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    width: 100%;
}
.message {
    width: 100%;
    opacity: 0;
    transform: translateY(10px);
    animation: messageSlideIn 0.3s ease forwards;
}
.message-content {
    padding: 1.25rem 1.5rem;
    border-radius: 1rem;
    font-size: 1rem;
    line-height: 1.7;
    background: var(--bg-secondary);
    border: 1px solid var(--border-primary);
    color: var(--text-primary);
}
.message-user .message-content {
    background: linear-gradient(135deg, rgba(67, 83, 255, 0.1), rgba(236, 72, 153, 0.1));
    border-color: var(--accent-primary);
}
@keyframes messageSlideIn {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}
@media (max-width: 768px) {
    .main-content {
        width: calc(100% - 32px);
        margin: 120px auto 60px;
        padding: 32px 24px 60px;
    }
    .quiz-card,
    .note-card,
    .analysis-card {
        padding: 1.75rem;
    }
    .question-header {
        flex-direction: column;
        align-items: flex-start;
    }
    .score-circle {
        width: 160px;
        height: 160px;
    }
    .score-percentage {
        font-size: 2.75rem;
    }
    .insight-grid {
        grid-template-columns: 1fr;
    }
}
@media (max-width: 480px) {
    .main-content {
        padding: 24px 20px 48px;
    }
    .quiz-card,
    .note-card,
    .analysis-card {
        padding: 1.5rem;
    }
    .option-item {
        padding: 1rem 1.25rem;
    }
}
.study-plan-options {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
    width: 100%;
    max-width: 700px;
    margin: 0 auto;
    padding: 2rem;
    background: var(--card-bg);
    border: 1px solid var(--card-bg-border);
    border-radius: 1.25rem;
    backdrop-filter: blur(20px) saturate(180%);
}
.study-plan-options > label {
    display: flex;
    align-items: center;
    gap: 1rem;
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--text-primary);
}
.study-plan-options input[type="date"],
.study-plan-options input[type="number"],
.study-plan-options input[type="text"] {
    flex: 1;
    padding: 0.875rem 1.25rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-primary);
    border-radius: 0.75rem;
    color: var(--text-primary);
    font-size: 1rem;
    font-family: inherit;
    transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    outline: none;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}
.study-plan-options input[type="date"]:hover,
.study-plan-options input[type="number"]:hover,
.study-plan-options input[type="text"]:hover {
    border-color: var(--border-secondary);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
}
.study-plan-options input[type="date"]:focus,
.study-plan-options input[type="number"]:focus,
.study-plan-options input[type="text"]:focus {
    border-color: var(--accent-primary);
    background: var(--bg-primary);
    box-shadow: 0 0 0 4px rgba(67, 83, 255, 0.1), 0 4px 12px rgba(0, 0, 0, 0.08);
    transform: translateY(-1px);
}
#startDate,
#endDate {
    min-width: 150px;
    cursor: pointer;
}
#startDate::-webkit-calendar-picker-indicator,
#endDate::-webkit-calendar-picker-indicator {
    cursor: pointer;
    filter: invert(0.5);
    transition: filter 0.2s ease;
}
#startDate::-webkit-calendar-picker-indicator:hover,
#endDate::-webkit-calendar-picker-indicator:hover {
    filter: invert(0.3);
}
[data-theme="dark"] #startDate::-webkit-calendar-picker-indicator,
[data-theme="dark"] #endDate::-webkit-calendar-picker-indicator,
body.dark #startDate::-webkit-calendar-picker-indicator,
body.dark #endDate::-webkit-calendar-picker-indicator {
    filter: invert(0.7);
}
[data-theme="dark"] #startDate::-webkit-calendar-picker-indicator:hover,
[data-theme="dark"] #endDate::-webkit-calendar-picker-indicator:hover,
body.dark #startDate::-webkit-calendar-picker-indicator:hover,
body.dark #endDate::-webkit-calendar-picker-indicator:hover {
    filter: invert(1);
}
#hoursPerDay {
    max-width: 120px;
    text-align: center;
    -moz-appearance: textfield;
}
#hoursPerDay::-webkit-outer-spin-button,
#hoursPerDay::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}
#studyGoal {
    width: 100%;
}
#studyGoal::placeholder {
    color: var(--text-tertiary);
    font-style: italic;
}
.learningStyle {
    width: 1.25rem;
    height: 1.25rem;
    margin-right: 0.5rem;
    cursor: pointer;
    accent-color: var(--accent-primary);
    border-radius: 0.25rem;
    transition: all 0.2s ease;
}
.learningStyle:checked {
    background: var(--accent-primary);
    border-color: var(--accent-primary);
}
.study-plan-options > div {
    display: flex;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
    padding: 1rem 0;
}
.study-plan-options > div label {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    font-weight: 500;
    color: var(--text-secondary);
    padding: 0.625rem 1rem;
    border-radius: 0.75rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-primary);
    transition: all 0.3s ease;
}
.study-plan-options > div label:hover {
    background: var(--bg-tertiary);
    border-color: var(--accent-primary);
    color: var(--text-primary);
}
.study-plan-options > div label:has(input:checked) {
    background: rgba(67, 83, 255, 0.1);
    border-color: var(--accent-primary);
    color: var(--accent-primary);
}
#output-language {
    width: 100%;
    max-width: 300px;
    margin: 0 auto;
}
.chat-container {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
}
.chat-messages {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    max-height: 500px;
    overflow-y: auto;
    padding: 1rem;
}
.chat-input-wrapper {
    display: flex;
    gap: 1rem;
    align-items: flex-end;
    padding: 1rem;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 1rem;
}
.chat-input-wrapper .textInput {
    flex: 1;
    min-height: 60px;
    resize: none;
}
.message-bubble {
    padding: 1.25rem 1.5rem;
    border-radius: 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-primary);
    color: var(--text-primary);
    line-height: 1.7;
    max-width: 75%;
    word-wrap: break-word;
}
.ai-message {
    align-self: flex-start !important;
    margin-right: auto;
}
.ai-message .message-bubble {
    border-radius: 1rem 1rem 1rem 0.25rem;
}
.user-message {
    align-self: flex-end !important;
    margin-left: auto;
}
.user-message .message-bubble {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-pink));
    color: white;
    border: none;
    border-radius: 1rem 1rem 0.25rem 1rem;
}
.status-wrapper {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    padding: 1rem;
}
.status-text {
    font-size: 1rem;
    color: var(--text-secondary);
    font-weight: 500;
}
.score-card {
    text-align: center;
    padding: 3rem 2rem;
    background: var(--card-bg);
    backdrop-filter: blur(20px) saturate(180%);
    border: 1px solid var(--card-bg-border);
    border-radius: 2rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow-lg);
}
.score-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 2rem;
}
.overall-score {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 2rem;
}
.score-value {
    font-size: 5rem;
    font-weight: 800;
    line-height: 1;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-pink));
    -webkit-background-clip: text;
    background-clip: text;
}
.score-subtitle {
    font-size: 0.95rem;
    color: var(--text-tertiary);
    margin-top: 0.5rem;
}
.interpretation {
    padding: 1.25rem 1.75rem;
    border-radius: 1rem;
    font-size: 1rem;
    line-height: 1.6;
}
.interpretation.excellent {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success);
    border: 1px solid rgba(16, 185, 129, 0.3);
}
.interpretation.good {
    background: rgba(59, 130, 246, 0.1);
    color: var(--info);
    border: 1px solid rgba(59, 130, 246, 0.3);
}
.interpretation.needs-work {
    background: rgba(245, 158, 11, 0.1);
    color: var(--warning);
    border: 1px solid rgba(245, 158, 11, 0.3);
}
.interpretation.poor {
    background: rgba(239, 68, 68, 0.1);
    color: var(--error);
    border: 1px solid rgba(239, 68, 68, 0.3);
}
.result-header {
    text-align: center;
    padding: 2rem;
    margin-bottom: 2rem;
}
.result-stats {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-top: 1rem;
    font-size: 1rem;
    color: var(--text-secondary);
}
.result-actions {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-top: 2rem;
    flex-wrap: wrap;
}
.action-buttons {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin: 2rem 0;
    flex-wrap: wrap;
}
.footer-actions {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-top: 3rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-primary);
    flex-wrap: wrap;
}
.sections-container {
    margin-top: 3rem;
}
.sections-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 2rem;
    text-align: center;
}
.section-card {
    background: var(--card-bg);
    border: 1px solid var(--card-bg-border);
    border-radius: 1.5rem;
    padding: 2rem;
    margin-bottom: 1.5rem;
    transition: all 0.3s ease;
}
.section-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(67, 83, 255, 0.1);
    border-color: var(--accent-primary);
}
.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
    gap: 1rem;
}
.section-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
}
.section-content {
    margin-top: 1.5rem;
    padding: 1.25rem;
    border-radius: 0.75rem;
    background: var(--bg-secondary);
}
.content-title {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 1rem;
}
.issues-title {
    color: var(--error);
}
.why-title {
    color: var(--warning);
}
.suggestions-title {
    color: var(--success);
}
.issues-section {
    border-left: 4px solid var(--error);
}
.suggestions-section {
    border-left: 4px solid var(--success);
}
.content-list {
    margin: 0;
    padding-left: 1.5rem;
}
.content-list li {
    margin-bottom: 0.75rem;
    color: var(--text-secondary);
    line-height: 1.6;
    list-style: disc;
}
.next-steps {
    margin-top: 3rem;
    padding: 2rem;
    background: var(--card-bg);
    border: 1px solid var(--card-bg-border);
    border-radius: 1.5rem;
}
.next-steps h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1.5rem;
}
.steps-list {
    padding-left: 1.5rem;
}
.steps-list li {
    margin-bottom: 1rem;
    color: var(--text-secondary);
    line-height: 1.6;
    list-style: decimal;
}
.inline-link {
    color: var(--accent-primary);
    font-weight: 500;
    text-decoration: underline;
    text-underline-offset: 2px;
    transition: color 0.2s ease;
}
.inline-link:hover {
    color: var(--accent-primary-hover);
}
.error-container {
    text-align: center;
    padding: 4rem 2rem;
}
.error-icon {
    font-size: 4rem;
    margin-bottom: 1.5rem;
}
.error-container h2 {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1rem;
}
.error-container p {
    color: var(--text-secondary);
    max-width: 500px;
    margin: 0 auto 2rem;
}
.md-content {
    text-align: left;
    line-height: 1.8;
    color: var(--text-primary);
}
.md-content h1,
.md-content h2,
.md-content h3,
.md-content h4,
.md-content h5,
.md-content h6 {
    margin-top: 2rem;
    margin-bottom: 1rem;
}
.md-content p {
    margin-bottom: 1rem;
}
.md-content ul,
.md-content ol {
    padding-left: 2rem;
    margin-bottom: 1rem;
}
.md-content li {
    margin-bottom: 0.5rem;
    list-style: inherit;
}
.md-content code {
    background: var(--bg-tertiary);
    padding: 0.2em 0.4em;
    border-radius: 0.25rem;
    font-family: var(--font-mono);
    font-size: 0.875em;
}
.md-content pre {
    background: var(--bg-tertiary);
    padding: 1rem;
    border-radius: 0.75rem;
    overflow-x: auto;
    margin: 1rem 0;
}
.md-content pre code {
    background: none;
    padding: 0;
}
.md-content blockquote {
    border-left: 4px solid var(--accent-primary);
    padding-left: 1rem;
    margin: 1rem 0;
    color: var(--text-secondary);
    font-style: italic;
}
.md-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
}
.md-content th,
.md-content td {
    border: 1px solid var(--border-primary);
    padding: 0.75rem;
    text-align: left;
}
.md-content th {
    background: var(--bg-secondary);
    font-weight: 600;
}
.Enhanced {
    padding: 2rem;
}
.dropdown-open {
    opacity: 1 !important;
    pointer-events: auto !important;
    transform: translateY(0) !important;
}
.user-menu-wrapper {
    position: relative;
}
.user-menu {
    min-width: 240px;
}
.menu-header {
    padding: 1rem;
    border-bottom: 1px solid var(--border-primary);
}
.usage-badge {
    font-size: 0.875rem;
    font-weight: 600;
}
.menu-icon {
    flex-shrink: 0;
}
.menu-divider {
    border: none;
    border-top: 1px solid var(--border-primary);
    margin: 0.5rem 0;
}
.dropdown-item.danger {
    color: var(--error);
}
.dropdown-item.danger:hover {
    background: rgba(239, 68, 68, 0.1);
}
.page-content-wrapper {
    padding-top: var(--header-height);
}
.link-primary {
    color: var(--accent-primary);
    transition: color 0.2s ease;
}
.link-primary:hover {
    color: var(--accent-primary-hover);
}
.button.secondary {
    background: var(--card-bg);
    color: var(--text-primary);
    border: 1px solid var(--border-primary);
    box-shadow: var(--shadow-sm);
}
.button.secondary:hover {
    background: var(--card-bg-hover);
    border-color: var(--accent-primary);
    transform: translateY(-2px);
}
.button.primary {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-pink));
    color: white;
    border: none;
}
.button.export {
    background: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border-primary);
}
.button.export:hover {
    background: var(--bg-tertiary);
    border-color: var(--accent-primary);
}
.submit-quiz {
    min-width: 200px;
}
.textInput.slimmest {
    min-height: 50px;
    padding: 0.875rem 1rem;
}
.textInput.standard {
    min-height: 200px;
}
.customModelSelector,
.FreeUsage {
    display: flex;
    align-items: center;
    justify-content: center;
}
.customModelInput {
    max-width: 700px;
    width: 100%;
}
#quizContainer {
    display: flex;
    flex-direction: column;
    gap: 2rem;
    width: 100%;
}
#resultsList {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}
.theme-icon {
    display: flex;
    align-items: center;
    justify-content: center;
}
.z-fixed {
    z-index: var(--z-fixed);
}
.z-50 {
    z-index: 50;
}
.fixed {
    position: fixed;
}
.top-0 { top: 0; }
.left-0 { left: 0; }
.right-0 { right: 0; }
.bottom-6 { bottom: 1.5rem; }
.right-6 { right: 1.5rem; }
.inset-0 {
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
}
.text-error {
    color: var(--error) !important;
}
.bg-error-soft {
    background: rgba(239, 68, 68, 0.1);
}
.bg-secondary {
    background: var(--bg-secondary);
}
.bg-card {
    background: var(--card-bg);
}
.border-b {
    border-bottom: 1px solid var(--border-primary);
}
.border-t {
    border-top: 1px solid var(--border-primary);
}
.border-primary {
    border-color: var(--border-primary);
}
.shadow-sm {
    box-shadow: var(--shadow-sm);
}
.shadow-xl {
    box-shadow: var(--shadow-xl);
}
.hover\:shadow-xl:hover {
    box-shadow: var(--shadow-xl);
}
.container {
    width: 100%;
    max-width: var(--container-xl);
    margin-left: auto;
    margin-right: auto;
    padding-left: 1.5rem;
    padding-right: 1.5rem;
}
.mr-1 { margin-right: 0.25rem; }
.mx-2 { margin-left: 0.5rem; margin-right: 0.5rem; }
.py-12 { padding-top: 3rem; padding-bottom: 3rem; }
.px-6 { padding-left: 1.5rem; padding-right: 1.5rem; }
.py-4 { padding-top: 1rem; padding-bottom: 1rem; }
.py-3 { padding-top: 0.75rem; padding-bottom: 0.75rem; }
.px-4 { padding-left: 1rem; padding-right: 1rem; }
.px-2 { padding-left: 0.5rem; padding-right: 0.5rem; }
.mt-2 { margin-top: 0.5rem; }
.my-2 { margin-top: 0.5rem; margin-bottom: 0.5rem; }
.mb-0 { margin-bottom: 0; }
.m-0 { margin: 0; }
.w-8 { width: 2rem; }
.h-8 { height: 2rem; }
.w-64 { width: 16rem; }
.import {
    display: none;
}
.pfp {
    object-fit: cover;
}
.duckai-icon {
    width: 80px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(67, 83, 255, 0.1), rgba(236, 72, 153, 0.1));
    border-radius: 1.5rem;
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    transition: all 0.3s ease;
    box-shadow: 0 8px 24px rgba(67, 83, 255, 0.15);
}
.benefits-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}
.benefit-card {
    padding: 2rem;
    text-align: center;
    transition: all 0.3s ease;
}
.benefit-icon {
    font-size: 3rem;
    margin-bottom: 1.5rem;
}
.results-container {
    max-width: 900px;
    margin: 0 auto;
}
.QuizResult .main {
    max-width: 900px;
    margin: 0 auto;
}
@media (max-width: 768px) {
    .study-plan-options {
        padding: 1rem;
    }
    .study-plan-options label {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5rem;
    }
    .chat-input-wrapper {
        flex-direction: column;
    }
    .action-buttons,
    .footer-actions,
    .result-actions {
        flex-direction: column;
        align-items: center;
    }
    .section-header {
        flex-direction: column;
        align-items: flex-start;
    }
    .score-value {
        font-size: 4rem;
    }
    .result-stats {
        flex-direction: column;
        gap: 0.5rem;
    }
}
@media (max-width: 480px) {
    .chat-messages {
        padding: 0.5rem;
    }
    .ai-message .message-bubble,
    .message-bubble {
        padding: 1rem;
    }
    .next-steps {
        padding: 1.5rem;
    }
    .section-card {
        padding: 1.5rem;
    }
    .score-card {
        padding: 2rem 1.5rem;
    }
}
.message.ai-message .message-bubble {
    background: var(--bg-secondary);
    border: 1px solid var(--border-primary);
    color: var(--text-primary);
    border-radius: 1rem 1rem 1rem 0.25rem;
}
.message.user-message .message-bubble {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-pink));
    color: white;
    border: none;
    border-radius: 1rem 1rem 0.25rem 1rem;
}
.header {
  position: sticky;
  top: 0;
  width: 100%;
  z-index: var(--z-sticky, 1100);
  background-image: url("/static/img/duck.jpg");
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
  transition: all var(--transition-base);
}

[data-theme="dark"] .header,
body.dark .header {
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
}


.header.scrolled {
  box-shadow: 0 12px 48px rgba(0, 0, 0, 0.12);
  backdrop-filter: blur(30px);
}


.header-nav {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: var(--header-nav-gap);
  padding: var(--chatbot-input-padding) 2rem;
  width: 100%;
  margin: 0;
  position: relative;
  z-index: 10;
  min-height: var(--header-nav-min-height);
}


.header-redirect {
  justify-self: start;
  display: inline-flex;
  align-items: center;
  gap: var(--space-3, 0.75rem);
  color: var(--text-primary);
  font-size: var(--text-base, 1rem);
  font-weight: var(--font-semibold, 600);
  text-decoration: none;
  padding: var(--space-3, 0.75rem) var(--space-6, 1.5rem);
  border-radius: var(--radius-xl, 1rem);
  background: linear-gradient(135deg, rgba(67, 83, 255, 0.1), rgba(236, 72, 153, 0.1));
  border: 2px solid var(--border-primary);
  transition: all var(--transition-base);
  box-shadow: 0 4px 12px rgba(67, 83, 255, 0.1);
}

.header-redirect:hover {
  background: linear-gradient(135deg, rgba(67, 83, 255, 0.2), rgba(236, 72, 153, 0.2));
  border-color: var(--accent-primary);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(67, 83, 255, 0.2);
}

.header-redirect:active {
  transform: translateY(0);
}

.donate-icon {
  width: 20px;
  height: 20px;
  color: var(--accent-primary);
  transition: color var(--transition-fast);
}

.header-redirect:hover .donate-icon {
  color: var(--accent-pink);
  filter: drop-shadow(0 0 8px rgba(236, 72, 153, 0.6));
}


.header-brand {
  display: flex;
  justify-content: center;
  align-items: center;
  grid-column: 2;
}

.header-text {
  display: inline-flex;
  align-items: center;
  gap: var(--space-4, 1rem);
  color: var(--text-primary);
  font-size: clamp(1.5rem, 4vw, 2.25rem);
  font-weight: var(--font-extrabold, 800);
  line-height: var(--leading-tight, 1.25);
  margin: 0;
  transition: all var(--transition-base);
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.header-text a {
  color: inherit;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: var(--space-3, 0.75rem);
  transition: all var(--transition-base);
}

.header-text a:hover {
  color: var(--accent-primary);
  text-shadow: 0 4px 16px rgba(67, 83, 255, 0.4);
}

.brand-icon {
  font-size: 1.6em;
  line-height: 1;
  transition: all var(--transition-base);
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1));
}

.header-text a:hover .brand-icon {
  transform: scale(1.1) rotate(5deg);
  filter: drop-shadow(0 4px 12px rgba(67, 83, 255, 0.6));
}


@keyframes subtle-float {
  0%, 100% {
    transform: translateY(0px);
  }
  50% {
    transform: translateY(-3px);
  }
}

.brand-icon {
  animation: subtle-float 3s ease-in-out infinite;
}


@media (prefers-reduced-motion: reduce) {
  .brand-icon {
    animation: none;
  }
}


.header-actions {
  justify-self: end;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--space-5, 1.25rem);
}

.auth-links {
  display: flex;
  align-items: center;
  gap: var(--space-4, 1rem);
}

.header-link {
  color: var(--text-primary);
  font-size: var(--text-base, 1rem);
  font-weight: var(--font-semibold, 600);
  text-decoration: none;
  padding: var(--space-3, 0.75rem) var(--space-5, 1.25rem);
  border-radius: var(--radius-lg, 0.75rem);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.header-link::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(67, 83, 255, 0.1), rgba(236, 72, 153, 0.1));
  opacity: 0;
  transition: opacity var(--transition-base);
}

.header-link:hover::before {
  opacity: 1;
}

.header-link:hover {
  color: var(--accent-primary);
  transform: translateY(-2px);
}

.header-link-primary {
  background: linear-gradient(135deg, #4353ff, #ec4899);
  color: var(--text-inverse);
  border: none;
  box-shadow: 0 8px 24px rgba(67, 83, 255, 0.3);
  position: relative;
  overflow: hidden;
}

.header-link-primary::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, #5865ff, #f472b6);
  opacity: 0;
  transition: opacity var(--transition-base);
}

.header-link-primary:hover::before {
  opacity: 1;
}

.header-link-primary:hover {
  color: var(--text-inverse);
  transform: translateY(-2px) scale(1.02);
  box-shadow: 0 12px 36px rgba(67, 83, 255, 0.4), 0 0 40px rgba(236, 72, 153, 0.3);
}

.header-link-primary:active {
  transform: translateY(0);
}

.divider {
  color: var(--text-tertiary);
  font-size: var(--text-base, 1rem);
  user-select: none;
  opacity: 0.5;
}


.free-uses {
  color: var(--accent-primary);
  font-size: var(--text-sm, 0.875rem);
  font-weight: var(--font-bold, 700);
  padding: var(--space-2-5, 0.625rem) var(--space-4, 1rem);
  background: linear-gradient(135deg, rgba(67, 83, 255, 0.15), rgba(0, 212, 170, 0.15));
  border: 2px solid var(--accent-primary);
  border-radius: var(--radius-full, 9999px);
  white-space: nowrap;
  display: inline-flex;
  align-items: center;
  gap: var(--space-2, 0.5rem);
  box-shadow: 0 4px 12px rgba(67, 83, 255, 0.2);
  animation: pulse-glow 2s ease-in-out infinite;
}

@keyframes pulse-glow {
  0%, 100% {
    box-shadow: 0 4px 12px rgba(67, 83, 255, 0.2);
  }
  50% {
    box-shadow: 0 4px 20px rgba(67, 83, 255, 0.4), 0 0 30px rgba(67, 83, 255, 0.2);
  }
}


.user-menu-wrapper {
  position: relative;
}

.user-menu-toggle {
  display: flex;
  align-items: center;
  gap: var(--space-3, 0.75rem);
  background: var(--card-bg);
  border: 2px solid var(--border-primary);
  border-radius: var(--radius-full, 9999px);
  color: var(--text-primary);
  cursor: pointer;
  transition: all var(--transition-base);
  padding: 0.5rem 1rem 0.5rem 0.5rem !important; 
  min-height: auto !important;
}

.user-menu-toggle:hover {
  background: var(--card-bg-hover);
  border-color: var(--accent-primary);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(67, 83, 255, 0.15);
}

.user-menu-toggle:active {
  transform: translateY(0);
}

.user-menu-toggle:focus-visible {
  outline: 2px solid var(--accent-primary);
  outline-offset: 2px;
}

.user-avatar {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full, 9999px);
  object-fit: cover;
  border: 2px solid var(--border-primary);
  transition: all var(--transition-base);
}

.user-menu-toggle:hover .user-avatar {
  border-color: var(--accent-primary);
  box-shadow: 0 0 20px rgba(67, 83, 255, 0.4);
}

.menu-chevron {
  font-size: var(--text-sm, 0.875rem);
  color: var(--text-tertiary);
  transition: transform var(--transition-base), color var(--transition-base);
  line-height: 1;
}

.user-menu-toggle:hover .menu-chevron {
  color: var(--accent-primary);
}

.user-menu-toggle[aria-expanded="true"] .menu-chevron {
  transform: rotate(180deg);
}


.user-menu {
  position: absolute;
  top: calc(100% + var(--space-3, 0.75rem));
  right: 0;
  width: max-content;
  background: var(--card-bg);
  border: 2px solid var(--border-primary);
  border-radius: var(--radius-xl, 1rem);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
  padding: var(--space-3, 0.75rem);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-12px);
  pointer-events: none;
  transition: all var(--transition-base);
  z-index: var(--z-dropdown, 1000);
}

.user-menu.open,
.user-menu[aria-hidden="false"] {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
  pointer-events: all;
}

.menu-header {
  padding: var(--space-4, 1rem);
  border-bottom: 2px solid var(--border-primary);
  margin-bottom: var(--space-2, 0.5rem);
}

.usage-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2, 0.5rem);
  font-size: var(--text-sm, 0.875rem);
  font-weight: var(--font-bold, 700);
  color: var(--accent-primary);
  background: linear-gradient(135deg, rgba(67, 83, 255, 0.1), rgba(0, 212, 170, 0.1));
  border: 2px solid var(--accent-primary);
  padding: var(--space-2-5, 0.625rem) var(--space-4, 1rem);
  border-radius: var(--radius-lg, 0.75rem);
  white-space: nowrap;
  box-shadow: 0 4px 12px rgba(67, 83, 255, 0.2);
}

.badge-icon {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.user-menu-item {
  display: flex;
  align-items: center;
  gap: var(--space-3, 0.75rem);
  padding: var(--space-4, 1rem);
  color: var(--text-primary);
  font-size: var(--text-base, 1rem);
  font-weight: var(--font-medium, 500);
  text-decoration: none;
  border-radius: var(--radius-lg, 0.75rem);
  transition: all var(--transition-base);
  cursor: pointer;
}

.user-menu-item:hover {
  background: linear-gradient(135deg, rgba(67, 83, 255, 0.1), rgba(236, 72, 153, 0.05));
  color: var(--accent-primary);
  transform: translateX(4px);
}

.user-menu-item:active {
  background: var(--bg-tertiary);
}

.user-menu-item.danger {
  color: var(--error);
}

.user-menu-item.danger:hover {
  background: var(--error-soft, rgba(239, 68, 68, 0.1));
  color: var(--error-hover);
}

.menu-icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
}

.menu-divider {
  border: none;
  height: 2px;
  background: var(--border-primary);
  margin: var(--space-3, 0.75rem) 0;
}


@media (max-width: 1024px) {
  .header-nav {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: var(--header-nav-gap);
  padding: var(--chatbot-input-padding) 2rem;
  width: 100%;
  margin: 0;
  position: relative;
  z-index: 10;
  min-height: var(--header-nav-min-height);
}
}

@media (max-width: 768px) {
  .header-nav {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: var(--header-nav-gap);
  padding: var(--chatbot-input-padding) 2rem;
  width: 100%;
  margin: 0;
  position: relative;
  z-index: 10;
  min-height: var(--header-nav-min-height);
}

  .header-text {
    font-size: 1.5rem;
  }

  .brand-icon {
    font-size: 1.4em;
  }

  .free-uses {
    display: none;
  }

  .header-redirect span {
    display: none;
  }

  .header-redirect {
    padding: var(--space-3, 0.75rem);
    width: 44px;
    height: 44px;
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .header-nav {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: var(--header-nav-gap);
  padding: var(--chatbot-input-padding) 2rem;
  width: 100%;
  margin: 0;
  position: relative;
  z-index: 10;
  min-height: var(--header-nav-min-height);
}

  .header-text {
    font-size: 1.25rem;
  }

  .auth-links {
    gap: var(--space-2, 0.5rem);
  }

  .header-link {
    padding: var(--space-2, 0.5rem) var(--space-4, 1rem);
    font-size: var(--text-sm, 0.875rem);
  }

  .divider {
    display: none;
  }
}


.header-link:focus-visible,
.header-redirect:focus-visible {
  outline: 3px solid var(--accent-primary);
  outline-offset: 3px;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}


@media print {
  .header {
    position: static;
    box-shadow: none;
    border-bottom: 1px solid #000;
  }

  .header-redirect,
  .header-actions,
  .user-menu {
    display: none;
  }

  .header-nav {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    gap: var(--header-nav-gap);
    padding: var(--chatbot-input-padding) 2rem;
    width: 100%;
    margin: 0;
    position: relative;
    z-index: 10;
    min-height: var(--header-nav-min-height);
  }

  .header-brand {
    grid-column: 1;
  }
}