/* ============================================
   WEB DESIGN FORMULA GUIDE - STYLE SYSTEM
   ============================================ */

/* ============================================
   1. CSS VARIABLES (Design Tokens)
   ============================================ */
:root {
  /* Colors - Light Mode */
  --color-bg: #ffffff;
  --color-bg-soft: #f6f6f7;
  --color-bg-mute: #e9e9eb;
  --color-bg-alt: #f9fafb;
  
  --color-text: #1a1a2e;
  --color-text-soft: #3c3c43;
  --color-text-mute: #6b7280;
  
  --color-border: #e5e7eb;
  --color-border-soft: #f0f0f0;
  
  --color-primary: #6366f1;
  --color-primary-soft: #818cf8;
  --color-primary-bg: #eef2ff;
  
  --color-code-bg: #f8f8fc;
  --color-code-text: #1f2937;
  
  /* Sidebar */
  --sidebar-width: 280px;
  --sidebar-bg: var(--color-bg);
  --nav-height: 64px;
  
  /* Spacing (8pt Grid) */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 16px;
  --space-4: 24px;
  --space-5: 32px;
  --space-6: 40px;
  --space-7: 48px;
  --space-8: 64px;
  
  /* Typography */
  --font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'Fira Code', 'Consolas', monospace;
  
  --font-size-xs: 12px;
  --font-size-sm: 14px;
  --font-size-base: 16px;
  --font-size-lg: 18px;
  --font-size-xl: 20px;
  --font-size-2xl: 24px;
  --font-size-3xl: 32px;
  --font-size-4xl: 40px;
  
  --line-height-tight: 1.25;
  --line-height-normal: 1.6;
  
  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  
  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
}

/* Dark Mode */
[data-theme="dark"] {
  --color-bg: #0f0f1a;
  --color-bg-soft: #1a1a2e;
  --color-bg-mute: #252540;
  --color-bg-alt: #16162a;
  
  --color-text: #e4e4e7;
  --color-text-soft: #a1a1aa;
  --color-text-mute: #71717a;
  
  --color-border: #27273f;
  --color-border-soft: #1f1f35;
  
  --color-primary: #818cf8;
  --color-primary-soft: #a5b4fc;
  --color-primary-bg: #1e1b4b;
  
  --color-code-bg: #1a1a2e;
  --color-code-text: #e4e4e7;
  
  --sidebar-bg: var(--color-bg-soft);
}

/* ============================================
   2. RESET & BASE
   ============================================ */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-height) + var(--space-4));
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  line-height: var(--line-height-normal);
  color: var(--color-text);
  background-color: var(--color-bg);
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

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

a:hover {
  color: var(--color-primary-soft);
}

/* ============================================
   3. LAYOUT
   ============================================ */
.layout {
  display: flex;
  min-height: 100vh;
}

/* No Sidebar Layout (Landing Page) */
.layout.no-sidebar .sidebar {
  display: none;
}

.layout.no-sidebar .main-content {
  margin-left: 0;
  max-width: 1200px;
  margin-left: auto;
  margin-right: auto;
  padding: var(--space-6);
}

/* Notice Banner */
.notice-banner {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 36px;
  background: var(--color-primary);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-base);
  font-weight: 500;
  z-index: 101;
}

/* Top Navigation */
.top-nav {
  position: fixed;
  top: 36px;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-4);
  z-index: 100;
  backdrop-filter: blur(8px);
  background: rgba(255, 255, 255, 0.9);
}

[data-theme="dark"] .top-nav {
  background: rgba(15, 15, 26, 0.9);
}

.logo {
  font-size: var(--font-size-xl);
  font-weight: 700;
  color: var(--color-text);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.logo-icon {
  display: flex;
  align-items: center;
  justify-content: center;
}

.logo-icon svg {
  width: 24px;
  height: 24px;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

/* Theme Toggle */
.theme-toggle {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  border: none;
  background: var(--color-bg-soft);
  display: flex;
  align-items: center;
  justify-content: center;
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
  stroke: var(--color-text);
}

.theme-toggle:hover {
  background: var(--color-bg-mute);
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
  display: none;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  border: none;
  background: var(--color-bg-soft);
  color: var(--color-text);
  cursor: pointer;
  align-items: center;
  justify-content: center;
}

.mobile-menu-toggle svg {
  width: 20px;
  height: 20px;
  stroke: var(--color-text);
}

/* Sidebar */
.sidebar {
  position: fixed;
  top: calc(var(--nav-height) + 36px);
  left: 0;
  width: var(--sidebar-width);
  height: calc(100vh - var(--nav-height) - 36px);
  background: var(--sidebar-bg);
  border-right: 1px solid var(--color-border);
  overflow-y: auto;
  padding: var(--space-4);
  z-index: 50;
}

/* Sidebar Home Button */
.sidebar-home {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-4);
  margin-bottom: var(--space-4);
  background: var(--color-primary-bg);
  border: 1px solid var(--color-primary);
  border-radius: var(--radius-md);
  color: var(--color-primary);
  font-weight: 600;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.sidebar-home:hover {
  background: var(--color-primary);
  color: white;
}

.sidebar-home .home-icon {
  display: flex;
  align-items: center;
  justify-content: center;
}

.sidebar-home .home-icon svg {
  width: 18px;
  height: 18px;
}

[data-theme="dark"] .sidebar-home {
  background: rgba(99, 102, 241, 0.1);
}

[data-theme="dark"] .sidebar-home:hover {
  background: var(--color-primary);
}

.sidebar-home.active {
  background: var(--color-primary);
  color: white;
}

.sidebar-section {
  margin-bottom: var(--space-5);
}

.sidebar-title {
  font-size: var(--font-size-base);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-mute);
  margin-bottom: var(--space-2);
  padding: 0 var(--space-2);
}

.sidebar-nav {
  list-style: none;
}

.sidebar-nav a {
  display: block;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  color: var(--color-text-soft);
  font-size: var(--font-size-base);
  transition: all var(--transition-fast);
}

.sidebar-nav a:hover {
  background: var(--color-bg-soft);
  color: var(--color-text);
}

.sidebar-nav a.active {
  background: var(--color-primary-bg);
  color: var(--color-primary);
  font-weight: 500;
}

/* Main Content */
.main-content {
  flex: 1;
  margin-left: var(--sidebar-width);
  margin-top: calc(var(--nav-height) + 36px);
  padding: var(--space-6) var(--space-8);
  max-width: 900px;
}

/* ============================================
   4. TYPOGRAPHY
   ============================================ */
h1, h2, h3, h4, h5, h6 {
  color: var(--color-text);
  font-weight: 600;
  line-height: var(--line-height-tight);
}

h1 {
  font-size: var(--font-size-4xl);
  margin-bottom: var(--space-4);
}

h2 {
  font-size: var(--font-size-2xl);
  margin-top: var(--space-8);
  margin-bottom: var(--space-4);
  padding-bottom: var(--space-2);
  border-bottom: 1px solid var(--color-border);
}

h3 {
  font-size: var(--font-size-xl);
  margin-top: var(--space-6);
  margin-bottom: var(--space-3);
}

p {
  margin-bottom: var(--space-4);
  color: var(--color-text-soft);
}

.lead {
  font-size: var(--font-size-lg);
  color: var(--color-text-mute);
  margin-bottom: var(--space-6);
}

/* ============================================
   5. COMPONENTS
   ============================================ */

/* Section */
.section {
  margin-bottom: var(--space-8);
  padding-bottom: var(--space-6);
  border-bottom: 1px solid var(--color-border-soft);
}

.section:last-child {
  border-bottom: none;
}

/* Info Box */
.info-box {
  padding: var(--space-4);
  border-radius: var(--radius-lg);
  margin: var(--space-4) 0;
  border-left: 4px solid;
}

.info-box.tip {
  background: #ecfdf5;
  border-color: #10b981;
}

.info-box.important {
  background: #fef3c7;
  border-color: #f59e0b;
}

.info-box.warning {
  background: #fef2f2;
  border-color: #ef4444;
}

[data-theme="dark"] .info-box.tip {
  background: #064e3b;
}

[data-theme="dark"] .info-box.important {
  background: #78350f;
}

[data-theme="dark"] .info-box.warning {
  background: #7f1d1d;
}

.info-box-title {
  font-weight: 600;
  margin-bottom: var(--space-2);
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

/* Table */
.table-wrapper {
  overflow-x: auto;
  margin: var(--space-4) 0;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--font-size-base);
}

th, td {
  padding: var(--space-3);
  text-align: left;
  border-bottom: 1px solid var(--color-border);
}

th {
  background: var(--color-bg-soft);
  font-weight: 600;
  color: var(--color-text);
}

tr:hover {
  background: var(--color-bg-alt);
}

/* Code Block */
.code-block {
  position: relative;
  margin: var(--space-4) 0;
}

.code-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-2) var(--space-3);
  background: var(--color-bg-mute);
  border-radius: var(--radius-md) var(--radius-md) 0 0;
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
}

.copy-btn {
  padding: var(--space-1) var(--space-2);
  border: none;
  border-radius: var(--radius-sm);
  background: var(--color-bg);
  color: var(--color-text-mute);
  cursor: pointer;
  font-size: var(--font-size-base);
  transition: all var(--transition-fast);
}

.copy-btn:hover {
  background: var(--color-primary);
  color: white;
}

pre {
  margin: 0;
  padding: var(--space-4);
  background: var(--color-code-bg);
  border-radius: 0 0 var(--radius-md) var(--radius-md);
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: var(--font-size-base);
  line-height: 1.7;
  color: var(--color-code-text);
}

code {
  font-family: var(--font-mono);
  font-size: 0.9em;
}

:not(pre) > code {
  padding: 2px 6px;
  background: var(--color-bg-soft);
  border-radius: var(--radius-sm);
  color: var(--color-primary);
}

/* Formula Box */
.formula-box {
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  margin: var(--space-4) 0;
  font-family: var(--font-mono);
  font-size: var(--font-size-base);
}

.formula-box .formula-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-2) 0;
}

.formula-box .formula-item::before {
  content: '✅';
}

/* Color Swatch */
.color-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
  gap: var(--space-3);
  margin: var(--space-4) 0;
}

.color-swatch {
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--color-border);
}

.color-swatch-color {
  height: 60px;
}

.color-swatch-info {
  padding: var(--space-2);
  background: var(--color-bg);
  font-size: var(--font-size-base);
}

/* Demo Box */
.demo-box {
  background: var(--color-bg-soft);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  margin: var(--space-4) 0;
}

.demo-box-title {
  font-size: var(--font-size-base);
  text-transform: uppercase;
  color: var(--color-text-mute);
  margin-bottom: var(--space-3);
}

/* Spacing Demo */
.spacing-demo {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
}

.spacing-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.spacing-bar {
  height: 24px;
  background: var(--color-primary);
  border-radius: var(--radius-sm);
}

.spacing-label {
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
  white-space: nowrap;
}

/* ============================================
   VISUAL DEMO COMPONENTS
   ============================================ */

/* Visual Demo Container */
.visual-demo {
  background: var(--color-bg-soft);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  margin: var(--space-4) 0;
}

.visual-demo-label {
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
  text-transform: uppercase;
  margin-bottom: var(--space-3);
  letter-spacing: 0.05em;
}

/* Button Demo */
.btn-demo {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  align-items: center;
}

.demo-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--color-primary);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.demo-btn:hover {
  filter: brightness(1.1);
}

.demo-btn.xs { height: 24px; padding: 0 8px; font-size: 12px; }
.demo-btn.sm { height: 32px; padding: 0 12px; font-size: 14px; }
.demo-btn.md { height: 40px; padding: 0 16px; font-size: 14px; }
.demo-btn.lg { height: 48px; padding: 0 24px; font-size: 16px; }
.demo-btn.xl { height: 56px; padding: 0 32px; font-size: 18px; }

/* Typography Demo */
.typo-demo {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.typo-item {
  display: flex;
  align-items: baseline;
  gap: var(--space-4);
  padding: var(--space-2) 0;
  border-bottom: 1px solid var(--color-border-soft);
}

.typo-sample {
  flex: 1;
  color: var(--color-text);
}

.typo-info {
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
  white-space: nowrap;
}

/* Grid Demo */
.grid-demo {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 4px;
}

.grid-col {
  background: var(--color-primary);
  opacity: 0.7;
  height: 40px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 10px;
  font-weight: 600;
}

/* Color Ratio Demo (60-30-10) */
.color-ratio-demo {
  display: flex;
  height: 80px;
  border-radius: var(--radius-md);
  overflow: hidden;
}

.color-ratio-60 {
  flex: 6;
  background: #1a1a2e;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: var(--font-size-base);
}

.color-ratio-30 {
  flex: 3;
  background: #3d3d5c;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: var(--font-size-base);
}

.color-ratio-10 {
  flex: 1;
  background: #6366f1;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: var(--font-size-base);
}

/* Radius Demo */
.radius-demo {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
}

.radius-item {
  text-align: center;
}

.radius-box {
  width: 60px;
  height: 60px;
  background: var(--color-primary);
  margin-bottom: var(--space-2);
}

.radius-label {
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
}

/* Shadow Demo */
.shadow-demo {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-5);
}

.shadow-item {
  text-align: center;
}

.shadow-box {
  width: 80px;
  height: 60px;
  background: var(--color-bg);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-2);
}

.shadow-box.xs { box-shadow: 0 1px 2px rgba(0,0,0,0.05); }
.shadow-box.sm { box-shadow: 0 1px 3px rgba(0,0,0,0.1); }
.shadow-box.md { box-shadow: 0 4px 6px rgba(0,0,0,0.1); }
.shadow-box.lg { box-shadow: 0 10px 15px rgba(0,0,0,0.1); }
.shadow-box.xl { box-shadow: 0 20px 25px rgba(0,0,0,0.15); }

.shadow-label {
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
}

/* Aspect Ratio Demo */
.ratio-demo {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  align-items: flex-end;
}

.ratio-item {
  text-align: center;
}

.ratio-box {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-soft));
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: var(--font-size-base);
  font-weight: 600;
  margin-bottom: var(--space-2);
}

.ratio-box.r1-1 { width: 60px; height: 60px; }
.ratio-box.r4-3 { width: 80px; height: 60px; }
.ratio-box.r16-9 { width: 107px; height: 60px; }
.ratio-box.r9-16 { width: 34px; height: 60px; }

.ratio-label {
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
}

/* Z-Index Demo */
.zindex-demo {
  position: relative;
  height: 120px;
  background: var(--color-bg-mute);
  border-radius: var(--radius-md);
}

.zindex-layer {
  position: absolute;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-base);
  color: white;
  font-weight: 500;
}

.zindex-layer.base {
  left: 10px; top: 50px;
  width: 120px; height: 50px;
  background: #64748b;
}

.zindex-layer.dropdown {
  left: 60px; top: 40px;
  width: 100px; height: 40px;
  background: #6366f1;
}

.zindex-layer.modal {
  left: 100px; top: 25px;
  width: 90px; height: 70px;
  background: #ec4899;
}

.zindex-layer.toast {
  right: 20px; top: 10px;
  width: 80px; height: 30px;
  background: #22c55e;
}

/* Scanning Pattern Demo */
.pattern-demo {
  position: relative;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  height: 150px;
}

.pattern-demo.f-pattern::before {
  content: '';
  position: absolute;
  width: 90%;
  height: 3px;
  background: var(--color-primary);
  top: 20px;
  left: 10px;
}

.pattern-demo.f-pattern::after {
  content: '';
  position: absolute;
  width: 60%;
  height: 3px;
  background: var(--color-primary);
  top: 50px;
  left: 10px;
}

.pattern-arrow {
  position: absolute;
  font-size: 24px;
  color: var(--color-primary);
}

/* Touch Target Demo */
.touch-demo {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.touch-target {
  background: var(--color-primary-bg);
  border: 2px dashed var(--color-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-base);
  color: var(--color-primary);
}

.touch-target.bad { 
  width: 32px; 
  height: 32px; 
  border-color: #ef4444;
  background: #fef2f2;
  color: #ef4444;
}

.touch-target.good { 
  width: 44px; 
  height: 44px; 
  border-color: #22c55e;
  background: #ecfdf5;
  color: #22c55e;
}

/* Container Demo */
.container-demo {
  position: relative;
  background: linear-gradient(90deg, var(--color-bg-mute) 0%, var(--color-bg-mute) 100%);
  height: 60px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
}

.container-inner {
  background: var(--color-primary);
  height: 100%;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: var(--font-size-base);
}

/* ============================================
   6. RESPONSIVE
   ============================================ */
@media (max-width: 1024px) {
  .main-content {
    padding: var(--space-5) var(--space-4);
  }
}

@media (max-width: 768px) {
  .mobile-menu-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
  }
  
  .sidebar {
    transform: translateX(-100%);
    transition: transform var(--transition-normal);
    width: 100%;
    max-width: 300px;
  }
  
  .sidebar.open {
    transform: translateX(0);
  }
  
  .main-content {
    margin-left: 0;
    padding: var(--space-4) var(--space-3);
  }
  
  h1 {
    font-size: var(--font-size-3xl);
  }
  
  h2 {
    font-size: var(--font-size-xl);
  }
  
  .overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 40;
  }
  
  .overlay.active {
    display: block;
  }
}

/* ============================================
   7. UTILITIES
   ============================================ */
.text-mute {
  color: var(--color-text-mute);
}

.text-primary {
  color: var(--color-primary);
}

.mt-4 { margin-top: var(--space-4); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }

/* Scrollbar */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--color-bg);
}

::-webkit-scrollbar-thumb {
  background: var(--color-border);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-text-mute);
}

/* ============================================
   8. VISUAL DEMO STYLES
   ============================================ */

/* Loading State */
.loading {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 200px;
  color: var(--color-text-mute);
}

/* Content Area Transition */
#contentArea {
  transition: opacity 0.2s ease;
}

/* Layout Width Demo */
.layout-width-demo {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.layout-demo-item {
  background: var(--color-primary);
  color: white;
  padding: var(--space-3);
  border-radius: var(--radius-md);
  text-align: center;
  font-size: var(--font-size-base);
  font-weight: 500;
}

.layout-demo-item.full { width: 100%; }
.layout-demo-item.wide { width: 90%; margin: 0 auto; }
.layout-demo-item.standard { width: 80%; margin: 0 auto; }
.layout-demo-item.narrow { width: 60%; margin: 0 auto; }

/* Breakpoint Demo */
.breakpoint-demo {
  display: flex;
  gap: var(--space-2);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
  overflow-x: auto;
}

.bp-item {
  flex: 1;
  min-width: 80px;
  padding: var(--space-3);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  text-align: center;
}

.bp-label {
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-1);
}

.bp-value {
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
  font-family: var(--font-mono);
}

.bp-item.mobile-xs { border-top: 3px solid #ef4444; }
.bp-item.mobile-sm { border-top: 3px solid #f97316; }
.bp-item.tablet { border-top: 3px solid #eab308; }
.bp-item.desktop { border-top: 3px solid #22c55e; }
.bp-item.large { border-top: 3px solid #3b82f6; }

/* Grid Span Demo */
.grid-span-demo {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.span-row {
  display: flex;
  gap: var(--space-2);
}

.span-col {
  background: var(--color-primary);
  color: white;
  padding: var(--space-2);
  border-radius: var(--radius-sm);
  text-align: center;
  font-size: var(--font-size-base);
  font-weight: 500;
}

.span-col.span-12 { flex: 12; }
.span-col.span-8 { flex: 8; }
.span-col.span-6 { flex: 6; }
.span-col.span-4 { flex: 4; }
.span-col.span-3 { flex: 3; }

/* Spacing Context Demo */
.spacing-context-demo {
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.spacing-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  max-width: 300px;
  margin: 0 auto;
}

.spacing-card-header,
.spacing-card-footer {
  padding: var(--space-4);
  background: var(--color-bg-mute);
  font-size: var(--font-size-base);
  position: relative;
}

.spacing-card-body {
  padding: var(--space-3);
  font-size: var(--font-size-base);
  position: relative;
}

.spacing-indicator {
  font-size: var(--font-size-base);
  color: var(--color-primary);
  font-family: var(--font-mono);
}

/* Typography Demo */
.typography-demo {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.typo-item {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: var(--space-2) 0;
  border-bottom: 1px solid var(--color-border);
}

.typo-item:last-child {
  border-bottom: none;
}

.typo-sample {
  color: var(--color-text);
}

.typo-sample.display { font-size: 56px; line-height: 1.1; }
.typo-sample.h1 { font-size: 40px; line-height: 1.2; }
.typo-sample.h2 { font-size: 32px; line-height: 1.2; }
.typo-sample.h3 { font-size: 28px; line-height: 1.3; }
.typo-sample.h4 { font-size: 24px; line-height: 1.3; }
.typo-sample.body-lg { font-size: 18px; line-height: 1.5; }
.typo-sample.body { font-size: 16px; line-height: 1.5; }
.typo-sample.caption { font-size: 12px; line-height: 1.4; }

.typo-info {
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
  font-family: var(--font-mono);
}

/* Modular Scale Demo */
.modular-scale-demo {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.scale-group {
  padding-bottom: var(--space-4);
  border-bottom: 1px solid var(--color-border);
}

.scale-group:last-child {
  padding-bottom: 0;
  border-bottom: none;
}

.scale-title {
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-3);
}

.scale-items {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: var(--space-3);
}

.scale-item {
  color: var(--color-text);
}

/* Icon Size Demo */
.icon-size-demo {
  display: flex;
  align-items: flex-end;
  gap: var(--space-4);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.icon-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
}

.icon-box {
  background: var(--color-primary);
  border-radius: var(--radius-sm);
}

.icon-item span {
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
}

/* Touch Target Demo */
.touch-target-demo {
  display: flex;
  justify-content: center;
  padding: var(--space-6);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.touch-target {
  position: relative;
  width: 80px;
  height: 80px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.touch-inner {
  width: 24px;
  height: 24px;
  background: var(--color-primary);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 10px;
  color: white;
}

.touch-area {
  position: absolute;
  inset: 0;
  border: 2px dashed var(--color-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: flex-end;
  justify-content: center;
  padding-bottom: var(--space-1);
  font-size: var(--font-size-base);
  color: var(--color-primary);
}

/* Color Palette Demo */
.color-palette-demo {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.palette-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.palette-title {
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--color-text);
}

.palette-colors {
  display: flex;
  gap: var(--space-1);
}

.palette-colors.semantic {
  flex-wrap: wrap;
}

.color-swatch {
  flex: 1;
  min-width: 60px;
  height: 60px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-base);
  font-weight: 500;
}

/* Contrast Demo */
.contrast-demo {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.contrast-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
}

.contrast-sample {
  width: 80px;
  height: 60px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  border: 1px solid var(--color-border);
}

.contrast-ratio {
  font-size: var(--font-size-base);
  font-family: var(--font-mono);
}

.contrast-item.pass .contrast-ratio {
  color: #22c55e;
}

.contrast-item.fail .contrast-ratio {
  color: #ef4444;
}

/* Border Width Demo */
.border-width-demo {
  display: flex;
  gap: var(--space-4);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.border-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
}

.border-box {
  width: 60px;
  height: 60px;
  border-style: solid;
  border-color: var(--color-primary);
  border-radius: var(--radius-md);
  background: var(--color-bg);
}

.border-item span {
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
}

/* Shadow Dark Demo */
.shadow-dark-demo {
  display: flex;
  gap: var(--space-4);
  padding: var(--space-6);
  background: #1a1a2e;
  border-radius: var(--radius-lg);
}

.dark-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
}

.dark-box {
  width: 80px;
  height: 60px;
  background: #2d2d44;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: var(--font-size-base);
}

.shadow-method .dark-box {
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
}

.border-method .dark-box {
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.glow-method .dark-box {
  box-shadow: 0 0 20px rgba(99, 102, 241, 0.3);
}

.dark-item span {
  font-size: var(--font-size-base);
  color: rgba(255, 255, 255, 0.6);
}

/* Scanning Pattern Demos */
.scanning-demo {
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.scanning-demo .scan-area {
  position: relative;
  width: 100%;
  max-width: 400px;
  margin: 0 auto;
  padding: var(--space-4);
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  min-height: 200px;
}

/* F-Pattern */
.f-pattern .scan-line {
  position: absolute;
  background: rgba(239, 68, 68, 0.3);
  border-radius: 2px;
}

.f-pattern .scan-line.top {
  top: 20px;
  left: 20px;
  right: 40px;
  height: 8px;
}

.f-pattern .scan-line.middle {
  top: 60px;
  left: 20px;
  width: 60%;
  height: 8px;
}

.f-pattern .scan-line.vertical {
  top: 20px;
  left: 20px;
  width: 8px;
  height: 150px;
}

.f-pattern .scan-content {
  padding-top: 80px;
}

.f-pattern .scan-text {
  margin-bottom: var(--space-2);
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
}

.f-pattern .scan-text.primary {
  color: var(--color-text);
  font-weight: 600;
}

.f-pattern .scan-text.secondary {
  color: var(--color-text-soft);
}

/* Z-Pattern */
.z-pattern .scan-area {
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: auto 1fr auto;
  gap: var(--space-4);
  min-height: 250px;
}

.z-pattern .z-line {
  position: absolute;
  top: 50%;
  left: 20%;
  right: 20%;
  height: 2px;
  background: linear-gradient(90deg, transparent, rgba(239, 68, 68, 0.5), transparent);
  transform: rotate(20deg);
}

.z-pattern .z-point {
  padding: var(--space-2);
  background: var(--color-bg-mute);
  border-radius: var(--radius-sm);
  font-size: var(--font-size-base);
  text-align: center;
  font-weight: 500;
}

.z-pattern .z-point.top-left { grid-area: 1 / 1; }
.z-pattern .z-point.top-right { grid-area: 1 / 2; }
.z-pattern .z-point.center { grid-area: 2 / 1 / 3 / 3; display: flex; align-items: center; justify-content: center; }
.z-pattern .z-point.bottom-left { grid-area: 3 / 1; }
.z-pattern .z-point.bottom-right { grid-area: 3 / 2; background: var(--color-primary); color: white; }

/* Gutenberg Diagram */
.gutenberg-demo {
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: 1fr 1fr;
  gap: var(--space-2);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.gut-area {
  padding: var(--space-4);
  border-radius: var(--radius-md);
  text-align: center;
  font-size: var(--font-size-base);
  line-height: 1.4;
}

.gut-area.primary {
  background: rgba(34, 197, 94, 0.2);
  border: 1px solid rgba(34, 197, 94, 0.5);
}

.gut-area.strong {
  background: rgba(59, 130, 246, 0.2);
  border: 1px solid rgba(59, 130, 246, 0.5);
}

.gut-area.weak {
  background: rgba(156, 163, 175, 0.2);
  border: 1px solid rgba(156, 163, 175, 0.5);
}

.gut-area.terminal {
  background: rgba(239, 68, 68, 0.2);
  border: 1px solid rgba(239, 68, 68, 0.5);
}

/* Animation Duration Demo */
.duration-demo {
  display: flex;
  gap: var(--space-4);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.duration-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
}

.duration-box {
  width: 80px;
  height: 50px;
  background: var(--color-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: var(--font-size-base);
  font-weight: 500;
  cursor: pointer;
}

.duration-box.instant { transition: transform 50ms, background 50ms; }
.duration-box.fast { transition: transform 150ms, background 150ms; }
.duration-box.normal { transition: transform 250ms, background 250ms; }
.duration-box.slow { transition: transform 500ms, background 500ms; }

.duration-box:hover {
  transform: scale(1.1);
  background: var(--color-primary-soft);
}

.duration-item span {
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
}

/* Easing Demo */
.easing-demo {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
}

.easing-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.easing-track {
  flex: 1;
  height: 30px;
  background: var(--color-bg);
  border-radius: var(--radius-md);
  position: relative;
  overflow: hidden;
}

.easing-ball {
  position: absolute;
  left: 10px;
  top: 50%;
  transform: translateY(-50%);
  width: 20px;
  height: 20px;
  background: var(--color-primary);
  border-radius: 50%;
}

.easing-ball.animate {
  animation-duration: 1s;
  animation-fill-mode: forwards;
}

.easing-ball.linear.animate { animation-name: moveLinear; animation-timing-function: linear; }
.easing-ball.ease-in.animate { animation-name: moveLinear; animation-timing-function: cubic-bezier(0.4, 0, 1, 1); }
.easing-ball.ease-out.animate { animation-name: moveLinear; animation-timing-function: cubic-bezier(0, 0, 0.2, 1); }
.easing-ball.ease-in-out.animate { animation-name: moveLinear; animation-timing-function: cubic-bezier(0.4, 0, 0.2, 1); }

@keyframes moveLinear {
  from { left: 10px; }
  to { left: calc(100% - 30px); }
}

.easing-item span {
  width: 120px;
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
}

.play-btn {
  margin-top: var(--space-3);
  padding: var(--space-2) var(--space-4);
  background: var(--color-primary);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: var(--font-size-base);
  transition: background var(--transition-fast);
}

.play-btn:hover {
  background: var(--color-primary-soft);
}

/* Z-Index Demo */
.z-index-demo {
  position: relative;
  height: 300px;
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
  perspective: 1000px;
}

.z-layer {
  position: absolute;
  width: 120px;
  height: 80px;
  background: var(--color-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: var(--font-size-base);
  transform: translateX(calc(var(--offset) * 40px)) translateY(calc(var(--offset) * 25px));
  opacity: calc(0.5 + var(--offset) * 0.07);
  box-shadow: var(--shadow-md);
}

.z-label {
  background: rgba(0, 0, 0, 0.3);
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
}

/* Aspect Ratio Demo */
.aspect-ratio-demo {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border-radius: var(--radius-lg);
  align-items: flex-end;
}

.aspect-ratio-demo.portrait {
  align-items: flex-start;
}

.ratio-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
}

.ratio-box {
  width: 120px;
  background: var(--color-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: var(--font-size-base);
  font-weight: 500;
}

.aspect-ratio-demo.portrait .ratio-box {
  width: 80px;
}

.ratio-item span {
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
}

/* ============================================
   9. FOOTER
   ============================================ */
.page-footer {
  margin-top: var(--space-8);
  padding: var(--space-6) 0;
  border-top: 1px solid var(--color-border);
  color: var(--color-text-mute);
  text-align: center;
}

.page-footer p {
  margin-bottom: var(--space-2);
}

.page-footer p:last-child {
  margin-bottom: 0;
}

/* ============================================
   10. LANDING PAGE STYLES
   ============================================ */

/* Landing Page Layout */
.landing-page {
  max-width: 100%;
}

/* Hero Section */
.hero {
  text-align: center;
  padding: var(--space-8) var(--space-4);
  margin-bottom: var(--space-6);
}

.hero-title {
  font-size: clamp(2.5rem, 5vw, 3.5rem);
  font-weight: 800;
  color: var(--color-text);
  margin-bottom: var(--space-3);
  letter-spacing: -0.02em;
}

.hero-subtitle {
  font-size: var(--font-size-lg);
  color: var(--color-text-mute);
  margin-bottom: var(--space-6);
}

/* Search Container */
.search-container {
  position: relative;
  max-width: 600px;
  margin: 0 auto;
}

.search-input {
  width: 100%;
  padding: var(--space-4) var(--space-5);
  font-size: var(--font-size-base);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-xl);
  background: var(--color-bg);
  color: var(--color-text);
  outline: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.search-input::placeholder {
  color: var(--color-text-mute);
}

.search-input:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 4px var(--color-primary-bg);
}

[data-theme="dark"] .search-input:focus {
  box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.2);
}

/* Search Results Dropdown */
.search-results {
  position: absolute;
  top: calc(100% + var(--space-2));
  left: 0;
  right: 0;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  max-height: 300px;
  overflow-y: auto;
  z-index: 100;
  display: none;
}

.search-results.active {
  display: block;
}

.search-result-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-3) var(--space-4);
  cursor: pointer;
  transition: background var(--transition-fast);
}

.search-result-item:hover {
  background: var(--color-bg-soft);
}

.search-result-item:first-child {
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}

.search-result-item:last-child {
  border-radius: 0 0 var(--radius-lg) var(--radius-lg);
}

.search-result-title {
  font-weight: 500;
  color: var(--color-text);
}

.search-result-arrow {
  color: var(--color-text-mute);
}

.search-no-result {
  padding: var(--space-4);
  text-align: center;
  color: var(--color-text-mute);
}

/* Menu Cards Section */
.menu-cards-section {
  padding: 0 var(--space-2);
}

.section-label {
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--color-text-mute);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-4);
}

/* Menu Cards Grid */
.menu-cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--space-4);
}

/* Menu Card */
.menu-card {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-4);
  background: var(--color-bg-soft);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.menu-card:hover {
  border-color: var(--color-primary);
  background: var(--color-bg);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.menu-card-icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-bg);
  border-radius: var(--radius-md);
  color: var(--color-primary);
}

.menu-card-icon svg {
  width: 24px;
  height: 24px;
}

.menu-card-content {
  flex: 1;
  min-width: 0;
}

.menu-card-content h3 {
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-1);
}

.menu-card-content p {
  font-size: var(--font-size-base);
  color: var(--color-text-mute);
  line-height: 1.4;
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

.menu-card-arrow {
  font-size: var(--font-size-lg);
  color: var(--color-text-mute);
  flex-shrink: 0;
  transition: transform var(--transition-fast);
}

.menu-card:hover .menu-card-arrow {
  transform: translateX(4px);
  color: var(--color-primary);
}

/* Responsive adjustments for landing page */
@media (max-width: 768px) {
  .hero {
    padding: var(--space-6) var(--space-3);
  }

  .hero-title {
    font-size: 2rem;
  }

  .hero-subtitle {
    font-size: var(--font-size-base);
  }

  .search-input {
    padding: var(--space-3) var(--space-4);
  }

  .menu-cards-grid {
    grid-template-columns: 1fr;
  }

  .menu-card {
    padding: var(--space-3);
  }

  .menu-card-icon {
    width: 40px;
    height: 40px;
    font-size: 24px;
  }
}