/* ===================================
   SekiUI Demo - Modern Design System
   =================================== */

/* Design Tokens */
:root {
  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Monaco, Consolas, "Liberation Mono", "Courier New", monospace;

  /* Colors - Light Mode */
  --bg-primary: #ffffff;
  --bg-secondary: #f8f9fa;
  --bg-tertiary: #f0f1f3;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-tertiary: #64748b;
  --border-color: #e2e8f0;
  --border-light: #f1f5f9;

  /* Accent Colors */
  --accent-primary: #3b82f6;
  --accent-primary-light: #dbeafe;
  --accent-primary-dark: #1e40af;
  --accent-secondary: #8b5cf6;
  --accent-success: #10b981;
  --accent-warning: #f59e0b;
  --accent-error: #ef4444;

  /* Shadows */
  --shadow-xs: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);

  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;

  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;

  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Mode */
[data-theme="dark"] {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-tertiary: #334155;
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-tertiary: #94a3b8;
  --border-color: #334155;
  --border-light: #1e293b;

  --accent-primary-light: #1e3a8a;
}

/* ===================================
   Reset & Base Styles
   =================================== */

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  color: var(--text-primary);
  background-color: var(--bg-primary);
  line-height: 1.6;
  transition: background-color var(--transition-base), color var(--transition-base);
}

/* ===================================
   Page Layout
   =================================== */

.page-wrapper {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  background: linear-gradient(to bottom, var(--bg-primary), var(--bg-secondary));
}

/* ===================================
   Hero Header
   =================================== */

.hero-header {
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.05), rgba(139, 92, 246, 0.05));
  border-bottom: 1px solid var(--border-color);
  color: var(--text-primary);
  padding: var(--spacing-3xl) var(--spacing-xl);
  position: relative;
  overflow: hidden;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
}

.hero-header::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -10%;
  width: 500px;
  height: 500px;
  background: linear-gradient(135deg, rgba(59, 130, 246, 0.03), rgba(139, 92, 246, 0.03));
  border-radius: 50%;
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 600px;
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 800;
  margin-bottom: var(--spacing-sm);
  letter-spacing: -0.02em;
}

.hero-subtitle {
  font-size: clamp(1.125rem, 3vw, 1.5rem);
  font-weight: 600;
  margin-bottom: var(--spacing-md);
  opacity: 0.95;
}

.hero-description {
  font-size: 1rem;
  margin-bottom: var(--spacing-lg);
  opacity: 0.9;
}

.cdn-badge {
  display: inline-block;
  background: var(--accent-primary-light);
  border: 1px solid var(--accent-primary);
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-md);
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--accent-primary-dark);
}

/* Theme Toggle */
.theme-toggle {
  position: relative;
  z-index: 2;
}

.theme-btn {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  padding: var(--spacing-md);
  border-radius: var(--radius-lg);
  font-size: 1.25rem;
  cursor: pointer;
  transition: all var(--transition-base);
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
}

.theme-btn:hover {
  background: var(--bg-tertiary);
  border-color: var(--border-light);
  transform: scale(1.05);
}

.theme-btn:active {
  transform: scale(0.95);
}

/* ===================================
   Main Content Layout
   =================================== */

.main-content-wrapper {
  display: flex;
  flex: 1;
  gap: 0;
}

/* ===================================
   Sidebar Navigation
   =================================== */

.sidebar {
  width: 280px;
  background: var(--bg-secondary);
  border-right: 1px solid var(--border-color);
  padding: var(--spacing-lg);
  flex-shrink: 0;
  height: fit-content;
  position: sticky;
  top: 0;
  max-height: 100vh;
  overflow-y: auto;
}

.sidebar-header {
  margin-bottom: var(--spacing-lg);
}

.sidebar-header h2 {
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 0;
}

.component-nav {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.component-nav-item {
  padding: var(--spacing-md);
  background: var(--bg-primary);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-base);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  text-decoration: none;
  display: block;
}

.component-nav-item:hover {
  background: var(--bg-tertiary);
  border-color: var(--border-color);
  color: var(--text-primary);
}

.component-nav-item.active {
  background: var(--accent-primary-light);
  border-color: var(--accent-primary);
  color: var(--accent-primary-dark);
  font-weight: 600;
}

/* ===================================
   Main Content Area
   =================================== */

.main-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: auto;
}

/* ===================================
   Showcase Grid
   =================================== */

.showcase-grid {
  flex: 1;
  max-width: 1400px;
  margin: 0 auto;
  width: 100%;
  padding: var(--spacing-2xl) var(--spacing-xl);
  display: grid;
  gap: var(--spacing-2xl);
}

/* Component Sections */
.component-section {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: var(--spacing-2xl);
  transition: all var(--transition-base);
  box-shadow: var(--shadow-sm);
}

.component-section:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--accent-primary-light);
}

.component-section h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.component-section h2::before {
  content: '';
  display: inline-block;
  width: 4px;
  height: 24px;
  background: linear-gradient(to bottom, var(--accent-primary), var(--accent-secondary));
  border-radius: var(--radius-sm);
}

.component-section h3 {
  font-size: 1rem;
  font-weight: 600;
  margin: var(--spacing-xl) 0 var(--spacing-md) 0;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding-bottom: var(--spacing-sm);
  border-bottom: 1px solid var(--border-light);
}

/* Variant Groups */
.variant-group {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

.variant-wrapper {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  padding: var(--spacing-lg);
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-light);
  transition: all var(--transition-base);
}

.variant-wrapper:hover {
  background: var(--bg-tertiary);
  border-color: var(--border-color);
}

.variant-label {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-tertiary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--spacing-xs);
}

/* Dark Theme Section */
.dark-theme {
  background: linear-gradient(135deg, #0f172a, #1e293b);
  padding: var(--spacing-xl);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
}

/* ===================================
   Typography Showcase
   =================================== */

.typography-section {
  display: grid;
  gap: var(--spacing-lg);
}

.typography-example {
  padding: var(--spacing-lg);
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-light);
}

/* ===================================
   Footer
   =================================== */

.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: var(--spacing-xl);
  text-align: center;
  color: var(--text-tertiary);
  margin-top: auto;
}

/* ===================================
   Typography Styles
   =================================== */

h1, h2, h3, h4, h5, h6 {
  line-height: 1.2;
  font-weight: 600;
}

p {
  color: var(--text-secondary);
}

code {
  font-family: var(--font-mono);
  background: var(--bg-tertiary);
  padding: 2px 6px;
  border-radius: var(--radius-sm);
  font-size: 0.9em;
}

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

a:hover {
  color: var(--accent-primary-dark);
  text-decoration: underline;
}

/* ===================================
   Responsive Design
   =================================== */

@media (max-width: 1024px) {
  .sidebar {
    width: 240px;
  }
}

@media (max-width: 768px) {
  .page-wrapper {
    min-height: auto;
  }

  .hero-header {
    flex-direction: column;
    gap: var(--spacing-xl);
    padding: var(--spacing-2xl) var(--spacing-lg);
  }

  .hero-header::before {
    width: 300px;
    height: 300px;
  }

  .theme-toggle {
    align-self: flex-start;
  }

  .main-content-wrapper {
    flex-direction: column;
  }

  .sidebar {
    width: 100%;
    max-height: none;
    border-right: none;
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-lg);
  }

  .sidebar-header {
    margin-bottom: var(--spacing-md);
  }

  .component-nav {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: var(--spacing-md);
  }

  .showcase-grid {
    padding: var(--spacing-lg);
    gap: var(--spacing-lg);
  }

  .component-section {
    padding: var(--spacing-lg);
  }

  .variant-group {
    grid-template-columns: 1fr;
  }

  .variant-wrapper {
    padding: var(--spacing-md);
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 2rem;
  }

  .hero-subtitle {
    font-size: 1.125rem;
  }

  .cdn-badge {
    font-size: 0.75rem;
    padding: var(--spacing-sm) var(--spacing-md);
  }

  .component-section h2 {
    font-size: 1.25rem;
  }

  .showcase-grid {
    padding: var(--spacing-md);
  }

  .variant-wrapper {
    padding: var(--spacing-md);
  }
}

/* ===================================
   Animations
   =================================== */

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.component-section {
  animation: fadeIn var(--transition-slow) ease-out;
}

/* ===================================
   Utility Classes
   =================================== */

.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;
}