/* ==========================================================================
   LearnToday Design System 3.0 - Creative Revolution
   시각 디자이너 + UX 디자이너 협업 결과물
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700;800;900&family=Inter:wght@300;400;500;600;700;800;900&family=Noto+Sans+KR:wght@400;500;600;700;800;900&display=swap');

/* ==========================================================================
   🎨 Creative Color System - 감성과 기술의 조화
   ========================================================================== */

:root {
  /* 🌅 Primary - 학습의 열정 (Warm Coral Pink to Golden) */
  --color-passion-50: #FFF5F0;
  --color-passion-100: #FFE8DC;
  --color-passion-200: #FFCDB8;
  --color-passion-300: #FFB095;
  --color-passion-400: #FF9271;
  --color-passion-500: #FF6B6B;  /* Main */
  --color-passion-600: #FF5252;
  --color-passion-700: #E63946;
  --color-passion-800: #CC2936;
  --color-passion-900: #A61E27;

  /* 🔮 Secondary - 신뢰와 전문성 (Deep Indigo) */
  --color-trust-50: #F0F1FE;
  --color-trust-100: #E0E3FD;
  --color-trust-200: #C1C7FB;
  --color-trust-300: #9DA7F9;
  --color-trust-400: #7A87F7;
  --color-trust-500: #4A5FE6;  /* Main */
  --color-trust-600: #3A4FD8;
  --color-trust-700: #2D3FE8;
  --color-trust-800: #2332C5;
  --color-trust-900: #1A2699;

  /* ⚡ Accent - 혁신과 성장 (Vivid Cyan to Mint) */
  --color-innovation-50: #E5FFFF;
  --color-innovation-100: #CCFFF5;
  --color-innovation-200: #99FFEB;
  --color-innovation-300: #66FFE0;
  --color-innovation-400: #33FFD6;
  --color-innovation-500: #00D9FF;  /* Main */
  --color-innovation-600: #00BDDE;
  --color-innovation-700: #00A0BD;
  --color-innovation-800: #00839C;
  --color-innovation-900: #00667A;

  /* 🌈 상태 컬러 - 감성적 피드백 */
  --color-success: #10B981;
  --color-success-light: #34D399;
  --color-success-dark: #059669;

  --color-warning: #FBBF24;
  --color-warning-light: #FCD34D;
  --color-warning-dark: #F59E0B;

  --color-error: #EF4444;
  --color-error-light: #F87171;
  --color-error-dark: #DC2626;

  --color-info: #3B82F6;
  --color-info-light: #60A5FA;
  --color-info-dark: #2563EB;

  /* 🖤 Neutral System - 세련된 회색톤 */
  --color-white: #FFFFFF;
  --color-black: #000000;
  --color-gray-50: #FAFAFA;
  --color-gray-100: #F5F5F5;
  --color-gray-200: #E5E7EB;
  --color-gray-300: #D1D5DB;
  --color-gray-400: #9CA3AF;
  --color-gray-500: #6B7280;
  --color-gray-600: #4B5563;
  --color-gray-700: #374151;
  --color-gray-800: #1F2937;
  --color-gray-900: #111827;

  /* 📝 Semantic Text Colors */
  --text-primary: #0F172A;
  --text-secondary: #475569;
  --text-tertiary: #64748B;
  --text-muted: #94A3B8;
  --text-inverse: #FFFFFF;
  --text-link: var(--color-trust-600);
  --text-link-hover: var(--color-trust-700);

  /* 🎨 Background System */
  --bg-primary: #FFFFFF;
  --bg-secondary: #FAFAFA;
  --bg-tertiary: #F1F5F9;
  --bg-overlay: rgba(0, 0, 0, 0.6);
  --bg-overlay-light: rgba(0, 0, 0, 0.3);

  /* ✨ Glassmorphism 2.0 - 더욱 세련된 유리 효과 */
  --glass-bg: rgba(255, 255, 255, 0.85);
  --glass-bg-dark: rgba(255, 255, 255, 0.65);
  --glass-border: rgba(255, 255, 255, 0.3);
  --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
  --glass-blur: 24px;

  /* 🌈 Creative Gradients - 감성적 그라디언트 */
  --gradient-passion: linear-gradient(135deg, #FF6B6B 0%, #FFB84D 100%);
  --gradient-trust: linear-gradient(135deg, #4A5FE6 0%, #2D3FE8 100%);
  --gradient-innovation: linear-gradient(135deg, #00D9FF 0%, #00FFA3 100%);
  --gradient-sunset: linear-gradient(135deg, #FF6B6B 0%, #FFB84D 50%, #FF9271 100%);
  --gradient-ocean: linear-gradient(135deg, #00D9FF 0%, #4A5FE6 100%);
  --gradient-forest: linear-gradient(135deg, #10B981 0%, #059669 100%);
  --gradient-surface: linear-gradient(135deg, #FAFAFA 0%, #F1F5F9 100%);

  /* 🎭 Dynamic Hero Backgrounds */
  --gradient-hero-creative:
    radial-gradient(1400px 800px at 15% -25%, rgba(255, 107, 107, 0.18), transparent),
    radial-gradient(1000px 600px at 85% 5%, rgba(0, 217, 255, 0.15), transparent),
    radial-gradient(800px 400px at 50% 50%, rgba(74, 95, 230, 0.08), transparent),
    linear-gradient(180deg, #FAFAFA 0%, #F8FAFC 100%);

  --gradient-hero-warm:
    radial-gradient(1200px 700px at 20% -20%, rgba(255, 184, 77, 0.2), transparent),
    radial-gradient(900px 500px at 80% 10%, rgba(255, 107, 107, 0.15), transparent),
    linear-gradient(180deg, #FFFBF5 0%, #FFF5F0 100%);

  --gradient-hero-cool:
    radial-gradient(1200px 700px at 25% -15%, rgba(74, 95, 230, 0.15), transparent),
    radial-gradient(900px 500px at 75% 5%, rgba(0, 217, 255, 0.12), transparent),
    linear-gradient(180deg, #F8FAFC 0%, #F0F9FF 100%);

  /* 🔲 Border System */
  --border-color: #E5E7EB;
  --border-light: #F3F4F6;
  --border-focus: var(--color-trust-500);
  --border-width: 1px;
  --border-width-thick: 2px;

  /* 🎯 Border Radius - 더욱 다양한 곡률 */
  --radius-xs: 0.25rem;   /* 4px */
  --radius-sm: 0.5rem;    /* 8px */
  --radius-md: 0.75rem;   /* 12px */
  --radius-lg: 1rem;      /* 16px */
  --radius-xl: 1.5rem;    /* 24px */
  --radius-2xl: 2rem;     /* 32px */
  --radius-3xl: 2.5rem;   /* 40px */
  --radius-full: 9999px;

  /* 🌟 Elevated Shadow System - 더욱 입체적인 그림자 */
  --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 8px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 16px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 12px 24px rgba(0, 0, 0, 0.12);
  --shadow-2xl: 0 16px 32px rgba(0, 0, 0, 0.14);
  --shadow-3xl: 0 24px 48px rgba(0, 0, 0, 0.18);

  /* 🎨 Colored Shadows - 브랜드 컬러 그림자 */
  --shadow-passion: 0 8px 24px rgba(255, 107, 107, 0.25);
  --shadow-trust: 0 8px 24px rgba(74, 95, 230, 0.25);
  --shadow-innovation: 0 8px 24px rgba(0, 217, 255, 0.25);

  /* 📏 Dynamic Spacing System - 더욱 유연한 간격 */
  --space-0: 0;
  --space-px: 1px;
  --space-0-5: 0.125rem;  /* 2px */
  --space-1: 0.25rem;     /* 4px */
  --space-1-5: 0.375rem;  /* 6px */
  --space-2: 0.5rem;      /* 8px */
  --space-2-5: 0.625rem;  /* 10px */
  --space-3: 0.75rem;     /* 12px */
  --space-3-5: 0.875rem;  /* 14px */
  --space-4: 1rem;        /* 16px */
  --space-5: 1.25rem;     /* 20px */
  --space-6: 1.5rem;      /* 24px */
  --space-7: 1.75rem;     /* 28px */
  --space-8: 2rem;        /* 32px */
  --space-9: 2.25rem;     /* 36px */
  --space-10: 2.5rem;     /* 40px */
  --space-11: 2.75rem;    /* 44px */
  --space-12: 3rem;       /* 48px */
  --space-14: 3.5rem;     /* 56px */
  --space-16: 4rem;       /* 64px */
  --space-20: 5rem;       /* 80px */
  --space-24: 6rem;       /* 96px */
  --space-28: 7rem;       /* 112px */
  --space-32: 8rem;       /* 128px */
  --space-36: 9rem;       /* 144px */
  --space-40: 10rem;      /* 160px */
  --space-48: 12rem;      /* 192px */
  --space-56: 14rem;      /* 224px */
  --space-64: 16rem;      /* 256px */

  /* 📱 Advanced Typography System */
  --font-family-heading: 'Outfit', 'Noto Sans KR', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-family-body: 'Inter', 'Noto Sans KR', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-family-mono: 'SF Mono', 'Monaco', 'Inconsolata', 'Fira Code', monospace;

  /* 📏 Fluid Typography - 더욱 정교한 반응형 크기 */
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);        /* 12px → 14px */
  --text-sm: clamp(0.875rem, 0.825rem + 0.25vw, 1rem);         /* 14px → 16px */
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);        /* 16px → 18px */
  --text-lg: clamp(1.125rem, 1.05rem + 0.375vw, 1.25rem);      /* 18px → 20px */
  --text-xl: clamp(1.25rem, 1.15rem + 0.5vw, 1.5rem);          /* 20px → 24px */
  --text-2xl: clamp(1.5rem, 1.35rem + 0.75vw, 2rem);           /* 24px → 32px */
  --text-3xl: clamp(1.875rem, 1.65rem + 1.125vw, 2.5rem);      /* 30px → 40px */
  --text-4xl: clamp(2.25rem, 1.95rem + 1.5vw, 3rem);           /* 36px → 48px */
  --text-5xl: clamp(3rem, 2.5rem + 2.5vw, 4rem);               /* 48px → 64px */
  --text-6xl: clamp(3.75rem, 3rem + 3.75vw, 5rem);             /* 60px → 80px */
  --text-7xl: clamp(4.5rem, 3.5rem + 5vw, 6rem);               /* 72px → 96px */

  /* 🏋️ Font Weights */
  --font-light: 300;
  --font-normal: 400;
  --font-medium: 500;
  --font-semibold: 600;
  --font-bold: 700;
  --font-extrabold: 800;
  --font-black: 900;

  /* 📏 Line Heights */
  --leading-none: 1;
  --leading-tight: 1.25;
  --leading-snug: 1.375;
  --leading-normal: 1.5;
  --leading-relaxed: 1.625;
  --leading-loose: 1.8;
  --leading-extraloose: 2;

  /* 📝 Letter Spacing */
  --tracking-tighter: -0.05em;
  --tracking-tight: -0.025em;
  --tracking-normal: 0em;
  --tracking-wide: 0.025em;
  --tracking-wider: 0.05em;
  --tracking-widest: 0.1em;

  /* ⚡ Advanced Transitions - 더욱 자연스러운 움직임 */
  --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-bounce: 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
  --transition-elastic: 0.6s cubic-bezier(0.68, -0.55, 0.265, 1.55);

  /* 🎬 Animation Durations */
  --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-Index System */
  --z-base: 0;
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
  --z-notification: 1080;
  --z-maximum: 9999;

  /* 📱 Breakpoints */
  --breakpoint-xs: 475px;
  --breakpoint-sm: 640px;
  --breakpoint-md: 768px;
  --breakpoint-lg: 1024px;
  --breakpoint-xl: 1280px;
  --breakpoint-2xl: 1536px;

  /* 🎛️ Container System */
  --container-xs: 475px;
  --container-sm: 640px;
  --container-md: 768px;
  --container-lg: 1024px;
  --container-xl: 1280px;
  --container-2xl: 1536px;
  --container-max: 1600px;
  --container-padding: var(--space-6);
  --header-height: 80px;

  /* 🎯 Interactive Elements */
  --interactive-size-sm: 36px;
  --interactive-size-md: 44px;
  --interactive-size-lg: 52px;
}

/* ==========================================================================
   🔄 Modern CSS Reset & Base Styles
   ========================================================================== */

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  font-feature-settings: "kern" 1;
  font-kerning: normal;
}

body {
  font-family: var(--font-family-body);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--text-primary);
  background: var(--bg-primary);
  min-height: 100vh;
  overflow-x: hidden;
}

/* ==========================================================================
   📐 Layout Components
   ========================================================================== */

.container {
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-padding);
  width: 100%;
}

.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); }

.section {
  position: relative;
  padding-block: var(--space-24);
}

.section-tight { padding-block: var(--space-16); }
.section-spacious { padding-block: var(--space-32); }
.section-hero { padding-block: var(--space-40); }

/* ==========================================================================
   ✍️ Advanced Typography Components
   ========================================================================== */

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-family-heading);
  font-weight: var(--font-bold);
  line-height: var(--leading-tight);
  color: var(--text-primary);
  margin-bottom: var(--space-4);
  letter-spacing: var(--tracking-tight);
}

h1 {
  font-size: var(--text-5xl);
  font-weight: var(--font-extrabold);
  letter-spacing: var(--tracking-tighter);
}
h2 {
  font-size: var(--text-4xl);
  font-weight: var(--font-bold);
}
h3 {
  font-size: var(--text-3xl);
  font-weight: var(--font-bold);
}
h4 {
  font-size: var(--text-2xl);
  font-weight: var(--font-semibold);
}
h5 {
  font-size: var(--text-xl);
  font-weight: var(--font-semibold);
}
h6 {
  font-size: var(--text-lg);
  font-weight: var(--font-medium);
}

p {
  margin-bottom: var(--space-4);
  line-height: var(--leading-relaxed);
  color: var(--text-secondary);
}

.lead {
  font-size: var(--text-xl);
  line-height: var(--leading-loose);
  color: var(--text-tertiary);
}

a {
  color: var(--text-link);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--text-link-hover);
}

/* ==========================================================================
   🎯 Advanced Button System - 10+ Variations
   ========================================================================== */

.btn {
  /* Base Structure */
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);

  /* Sizing */
  min-height: var(--interactive-size-md);
  padding-inline: var(--space-6);
  padding-block: var(--space-3);

  /* Typography */
  font-family: var(--font-family-body);
  font-size: var(--text-base);
  font-weight: var(--font-semibold);
  line-height: 1;
  text-decoration: none;
  white-space: nowrap;

  /* Visual */
  border: var(--border-width) solid transparent;
  border-radius: var(--radius-lg);
  background: transparent;
  color: var(--text-primary);

  /* Interaction */
  cursor: pointer;
  user-select: none;
  transition: all var(--transition-base);
  -webkit-tap-highlight-color: transparent;
}

.btn:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 2px;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

/* Primary Variants */
.btn-primary {
  background: var(--gradient-passion);
  color: var(--text-inverse);
  box-shadow: var(--shadow-passion);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 28px rgba(255, 107, 107, 0.35);
}

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

/* Secondary Variant */
.btn-secondary {
  background: var(--gradient-trust);
  color: var(--text-inverse);
  box-shadow: var(--shadow-trust);
}

.btn-secondary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 28px rgba(74, 95, 230, 0.35);
}

/* Accent Variant */
.btn-accent {
  background: var(--gradient-innovation);
  color: var(--text-primary);
  box-shadow: var(--shadow-innovation);
}

.btn-accent:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 28px rgba(0, 217, 255, 0.35);
}

/* Outline Variant */
.btn-outline {
  background: transparent;
  color: var(--color-passion-600);
  border-color: currentColor;
}

.btn-outline:hover {
  background: var(--color-passion-50);
  border-color: var(--color-passion-600);
}

/* Ghost Variant */
.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
}

.btn-ghost:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

/* Glass Variant */
.btn-glass {
  background: var(--glass-bg);
  backdrop-filter: blur(var(--glass-blur));
  border: var(--border-width) solid var(--glass-border);
  color: var(--text-primary);
  box-shadow: var(--glass-shadow);
}

.btn-glass:hover {
  background: var(--glass-bg-dark);
  transform: translateY(-2px);
}

/* Soft Variant */
.btn-soft {
  background: var(--color-passion-100);
  color: var(--color-passion-700);
}

.btn-soft:hover {
  background: var(--color-passion-200);
}

/* Size Variants */
.btn-sm {
  min-height: var(--interactive-size-sm);
  padding-inline: var(--space-4);
  padding-block: var(--space-2);
  font-size: var(--text-sm);
}

.btn-lg {
  min-height: var(--interactive-size-lg);
  padding-inline: var(--space-8);
  padding-block: var(--space-4);
  font-size: var(--text-lg);
}

.btn-xl {
  min-height: 60px;
  padding-inline: var(--space-12);
  padding-block: var(--space-5);
  font-size: var(--text-xl);
  border-radius: var(--radius-xl);
}

/* Full Width */
.btn-block {
  width: 100%;
}

/* Icon Buttons */
.btn-icon {
  width: var(--interactive-size-md);
  height: var(--interactive-size-md);
  padding: 0;
  border-radius: var(--radius-md);
}

.btn-icon-sm {
  width: var(--interactive-size-sm);
  height: var(--interactive-size-sm);
}

.btn-icon-lg {
  width: var(--interactive-size-lg);
  height: var(--interactive-size-lg);
}

/* ==========================================================================
   🎴 Advanced Card System - Multiple Variations
   ========================================================================== */

.card {
  position: relative;
  background: var(--bg-primary);
  border: var(--border-width) solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-bounce);
  overflow: hidden;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
  border-color: var(--border-focus);
}

/* Card Variants */
.card-elevated {
  border: none;
  box-shadow: var(--shadow-lg);
}

.card-elevated:hover {
  box-shadow: var(--shadow-2xl);
}

.card-glass {
  background: var(--glass-bg);
  backdrop-filter: blur(var(--glass-blur));
  border: var(--border-width) solid var(--glass-border);
  box-shadow: var(--glass-shadow);
}

.card-gradient {
  background: var(--gradient-surface);
  border: none;
}

.card-bordered {
  background: transparent;
  border-width: var(--border-width-thick);
}

/* Card Interactive */
.card-interactive {
  cursor: pointer;
  user-select: none;
}

.card-interactive:hover {
  transform: translateY(-6px) scale(1.02);
}

.card-interactive:active {
  transform: translateY(-2px) scale(1);
}

/* Card Sizes */
.card-sm {
  padding: var(--space-4);
  border-radius: var(--radius-lg);
}

.card-lg {
  padding: var(--space-8);
  border-radius: var(--radius-2xl);
}

/* Card Header/Body/Footer */
.card-header {
  margin-bottom: var(--space-4);
  padding-bottom: var(--space-4);
  border-bottom: var(--border-width) solid var(--border-light);
}

.card-body {
  flex: 1;
}

.card-footer {
  margin-top: var(--space-4);
  padding-top: var(--space-4);
  border-top: var(--border-width) solid var(--border-light);
}

/* ==========================================================================
   📊 Advanced Grid Systems - Flexible Layouts
   ========================================================================== */

.grid {
  display: grid;
  gap: var(--space-6);
}

/* Standard Grids */
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
.grid-5 { grid-template-columns: repeat(5, 1fr); }
.grid-6 { grid-template-columns: repeat(6, 1fr); }

/* Auto-fit Grids */
.grid-auto-fit {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid-auto-fill {
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
}

/* Gap Variants */
.gap-2 { gap: var(--space-2); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.gap-8 { gap: var(--space-8); }
.gap-12 { gap: var(--space-12); }

/* Flex Utilities */
.flex {
  display: flex;
  gap: var(--space-4);
}

.flex-col { flex-direction: column; }
.flex-wrap { flex-wrap: wrap; }
.items-center { align-items: center; }
.items-start { align-items: flex-start; }
.items-end { align-items: flex-end; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.justify-end { justify-content: flex-end; }

/* ==========================================================================
   🎨 Utility Classes - Extensive Collection
   ========================================================================== */

/* Text Alignment */
.text-left { text-align: left; }
.text-center { text-align: center; }
.text-right { text-align: right; }

/* Text Colors */
.text-primary { color: var(--text-primary); }
.text-secondary { color: var(--text-secondary); }
.text-tertiary { color: var(--text-tertiary); }
.text-muted { color: var(--text-muted); }
.text-inverse { color: var(--text-inverse); }
.text-passion { color: var(--color-passion-600); }
.text-trust { color: var(--color-trust-600); }
.text-innovation { color: var(--color-innovation-600); }
.text-success { color: var(--color-success); }
.text-warning { color: var(--color-warning); }
.text-error { color: var(--color-error); }

/* Background Colors */
.bg-primary { background: var(--bg-primary); }
.bg-secondary { background: var(--bg-secondary); }
.bg-tertiary { background: var(--bg-tertiary); }
.bg-passion { background: var(--gradient-passion); }
.bg-trust { background: var(--gradient-trust); }
.bg-innovation { background: var(--gradient-innovation); }

/* Font Weights */
.font-light { font-weight: var(--font-light); }
.font-normal { font-weight: var(--font-normal); }
.font-medium { font-weight: var(--font-medium); }
.font-semibold { font-weight: var(--font-semibold); }
.font-bold { font-weight: var(--font-bold); }
.font-extrabold { font-weight: var(--font-extrabold); }

/* Display */
.hidden { display: none; }
.block { display: block; }
.inline-block { display: inline-block; }
.flex { display: flex; }
.inline-flex { display: inline-flex; }
.grid { display: grid; }

/* Visibility */
.visible { visibility: visible; }
.invisible { visibility: hidden; }

/* Overflow */
.overflow-hidden { overflow: hidden; }
.overflow-auto { overflow: auto; }
.overflow-x-auto { overflow-x: auto; }
.overflow-y-auto { overflow-y: auto; }

/* Position */
.relative { position: relative; }
.absolute { position: absolute; }
.fixed { position: fixed; }
.sticky { position: sticky; }

/* ==========================================================================
   🎬 Advanced Animation System
   ========================================================================== */

.animate-fade-in {
  animation: fadeIn var(--duration-700) var(--transition-base);
}

.animate-slide-up {
  animation: slideUp var(--duration-700) var(--transition-base);
}

.animate-slide-down {
  animation: slideDown var(--duration-700) var(--transition-base);
}

.animate-slide-left {
  animation: slideLeft var(--duration-700) var(--transition-base);
}

.animate-slide-right {
  animation: slideRight var(--duration-700) var(--transition-base);
}

.animate-scale-up {
  animation: scaleUp var(--duration-500) var(--transition-bounce);
}

.animate-bounce {
  animation: bounce var(--duration-1000) var(--transition-elastic) infinite;
}

/* Keyframes */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideLeft {
  from {
    opacity: 0;
    transform: translateX(30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes slideRight {
  from {
    opacity: 0;
    transform: translateX(-30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes scaleUp {
  from {
    opacity: 0;
    transform: scale(0.9);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

@keyframes bounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

/* ==========================================================================
   📱 Responsive Design System
   ========================================================================== */

@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .grid-3 { grid-template-columns: repeat(2, 1fr); }
  .grid-6 { grid-template-columns: repeat(3, 1fr); }

  .lg\:hidden { display: none; }
}

@media (max-width: 768px) {
  :root {
    --container-padding: var(--space-4);
    --header-height: 64px;
  }

  .section { padding-block: var(--space-16); }
  .section-spacious { padding-block: var(--space-20); }

  .grid-4,
  .grid-3,
  .grid-2,
  .grid-6,
  .grid-5 {
    grid-template-columns: 1fr;
  }

  .md\:hidden { display: none; }
  .md\:flex { display: flex; }
  .md\:block { display: block; }

  h1 { font-size: var(--text-4xl); }
  h2 { font-size: var(--text-3xl); }
  h3 { font-size: var(--text-2xl); }
}

@media (max-width: 640px) {
  .sm\:hidden { display: none; }
  .sm\:flex { display: flex; }
  .sm\:block { display: block; }
}

/* ==========================================================================
   ♿ Accessibility Features
   ========================================================================== */

/* Touch Optimization */
* {
  -webkit-tap-highlight-color: rgba(255, 107, 107, 0.2);
}

/* Focus Visible for Keyboard Navigation */
*:focus-visible {
  outline: 3px solid var(--color-passion-500);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* Touch Feedback */
button:active:not(:disabled),
a:active:not([aria-disabled="true"]),
[role="button"]:active:not([aria-disabled="true"]) {
  transform: scale(0.97);
}

/* Reduced Motion Support */
@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;
  }
}

/* Dark Mode Support (Future-ready) */
@media (prefers-color-scheme: dark) {
  :root {
    --text-primary: #F8FAFC;
    --text-secondary: #CBD5E1;
    --text-tertiary: #94A3B8;
    --text-muted: #64748B;
    --bg-primary: #0F172A;
    --bg-secondary: #1E293B;
    --bg-tertiary: #334155;
    --border-color: #334155;
    --border-light: #1E293B;
  }
}

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