:root {
  /* OKLCH Color Tokens */
  --bg-primary: oklch(100% 0 0);
  --bg-secondary: oklch(98% 0 0);
  --text-primary: oklch(20% 0 0);
  --text-secondary: oklch(45% 0 0);
  --accent-primary: oklch(60% 0.15 250); /* A refined blue accent */
  --border-subtle: oklch(92% 0 0);
  --border-strong: oklch(85% 0 0);

  /* Spacing Scale (4px base) */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 20px;
  --space-6: 24px;
  --space-8: 32px;
  --space-12: 48px;

  /* Typography */
  --font-sans: 'DM Sans', -apple-system, BlinkMacSystemFont, sans-serif;
}

/* Base Reset */
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

/* Top Bar */
.top-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--space-2) var(--space-6);
  border-bottom: 1px solid var(--border-subtle);
  background-color: var(--bg-primary);
  position: sticky;
  top: 0;
  z-index: 100;
}

.top-bar-left, .top-bar-right {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  text-decoration: none;
  color: var(--text-primary);
  font-weight: 700;
  font-size: 1.1rem;
}

.logo i {
  color: var(--accent-primary);
  font-size: 1.5rem;
}

.icon-btn {
  background: none;
  border: none;
  color: var(--text-secondary);
  font-size: 1.25rem;
  cursor: pointer;
  padding: var(--space-1);
  border-radius: var(--space-1);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s;
}

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

.search-container {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  background-color: var(--bg-secondary);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--space-1);
  border: 1px solid var(--border-subtle);
  width: 240px;
}

.search-container input {
  background: none;
  border: none;
  outline: none;
  font-family: var(--font-sans);
  font-size: 0.9rem;
  width: 100%;
}

#menu-toggle {
  display: none;
}

/* Layout - 24 Column Grid Logic */
.container {
  max-width: 1440px;
  margin: 0 auto;
  padding: 0 var(--space-6);
  display: grid;
  grid-template-columns: repeat(24, 1fr);
  gap: var(--space-4);
}

.sidebar {
  grid-column: 1 / span 5;
  position: sticky;
  top: 57px; /* top-bar height */
  height: calc(100vh - 57px);
  padding: var(--space-8) 0;
  border-right: 1px solid var(--border-subtle);
  overflow-y: auto;
}

.main-content {
  grid-column: 7 / span 12;
  padding-top: var(--space-8);
  padding-bottom: var(--space-12);
}

.right-rail {
  grid-column: 20 / span 5;
  position: sticky;
  top: 57px;
  height: calc(100vh - 57px);
  padding: var(--space-8) 0;
  overflow-y: auto;
}

/* Responsive Overrides */
@media (max-width: 1024px) {
  .top-bar {
    padding: var(--space-2) var(--space-4);
  }

  .search-container {
    display: none;
  }

  #menu-toggle {
    display: flex;
  }

  .container {
    display: block;
    padding: 0 var(--space-4);
  }
  
  .sidebar {
    position: fixed;
    top: 57px;
    left: -100%;
    width: 280px;
    background-color: var(--bg-primary);
    z-index: 90;
    transition: left 0.3s;
    border-right: 1px solid var(--border-subtle);
    padding: var(--space-4);
  }

  .sidebar.active {
    left: 0;
  }

  .main-content {
    padding-top: var(--space-4);
  }

  .right-rail {
    display: none;
  }
}
.Link {
  color: var(--accent-primary);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: all 0.2s;
}

.Link:hover {
  border-bottom-color: var(--accent-primary);
}

.Button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--space-1);
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
  border: 1px solid transparent;
}

.Input, .Select {
  width: 100%;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--space-1);
  border: 1px solid var(--border-strong);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 1rem;
  transition: all 0.2s;
  outline: none;
}

.Input:focus, .Select:focus {
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 2px oklch(60% 0.15 250 / 0.1);
}

.Input::placeholder {
  color: var(--text-secondary);
  opacity: 0.6;
}

.Button--primary {
  background-color: var(--accent-primary);
  color: white;
}

/* Breadcrumbs */
.breadcrumbs { font-size: 0.85rem; color: var(--text-secondary); margin-bottom: var(--space-4); display: flex; align-items: center; gap: var(--space-2); }
.breadcrumbs a { color: var(--text-secondary); text-decoration: none; transition: color 0.2s; }
.breadcrumbs a:hover { color: var(--accent-primary); }
.breadcrumbs .sep { color: var(--border-strong); }

.page-header h1 { font-size: 2.5rem; font-weight: 700; margin-bottom: var(--space-8); }

/* Navigation */
.nav-tree ul { list-style: none; padding-left: var(--space-4); }
.nav-tree > ul { padding-left: 0; }
.nav-tree li { margin-bottom: var(--space-2); }
.nav-tree a { text-decoration: none; color: var(--text-secondary); transition: color 0.2s; }
.nav-tree a:hover { color: var(--accent-primary); }
.nav-group { display: block; font-weight: 600; font-size: 0.8em; text-transform: uppercase; letter-spacing: 0.05em; color: var(--text-secondary); margin: var(--space-6) 0 var(--space-2); }

/* TOC */
.right-rail { grid-column: 20 / span 5; position: sticky; top: 0; height: 100vh; padding: var(--space-12) 0; }
.toc h3 { font-size: 0.8em; text-transform: uppercase; letter-spacing: 0.05em; color: var(--text-secondary); margin-bottom: var(--space-4); }
.toc ul { list-style: none; border-left: 1px solid var(--border-subtle); padding-left: var(--space-4); }
.toc li { margin-bottom: var(--space-2); }
.toc a { text-decoration: none; color: var(--text-secondary); font-size: 0.9em; transition: color 0.2s; }
.toc a:hover { color: var(--accent-primary); }
.toc-l3 { padding-left: var(--space-4); font-size: 0.85em; }

/* Dark Mode (Basic) */
[data-theme="dark"] {
  --bg-primary: oklch(15% 0 0);
  --bg-secondary: oklch(18% 0 0);
  --text-primary: oklch(95% 0 0);
  --text-secondary: oklch(75% 0 0);
  --accent-primary: oklch(70% 0.15 250);
  --border-subtle: oklch(25% 0 0);
  --border-strong: oklch(35% 0 0);
}

/* Preview Blocks */
.Preview-container {
  border: 1px solid var(--border-subtle);
  border-radius: var(--space-2);
  margin: var(--space-6) 0;
  overflow: hidden;
}

.Preview-canvas {
  padding: var(--space-8);
  background-color: var(--bg-secondary);
  display: flex;
  gap: var(--space-4);
  align-items: center;
  /* No flex-wrap as per spec */
}

.Preview-code {
  background-color: var(--bg-primary);
  border-top: 1px solid var(--border-subtle);
  padding: var(--space-4);
  font-family: monospace;
  font-size: 0.9em;
  overflow-x: auto;
}

/* Badges */
.Badge {
  display: inline-flex;
  align-items: center;
  padding: 2px var(--space-2);
  border-radius: var(--space-1);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background-color: var(--bg-secondary);
  color: var(--text-secondary);
  border: 1px solid var(--border-subtle);
}

.Badge--primary {
  background-color: var(--accent-primary);
  color: white;
  border-color: transparent;
}

.Badge--success { color: oklch(65% 0.15 150); border-color: oklch(65% 0.15 150 / 0.2); }
.Badge--warning { color: oklch(75% 0.15 80); border-color: oklch(75% 0.15 80 / 0.2); }
.Badge--error { color: oklch(60% 0.2 30); border-color: oklch(60% 0.2 30 / 0.2); }

/* Avatars */
.Avatar {
  width: var(--space-8);
  height: var(--space-8);
  border-radius: 50%;
  object-fit: cover;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-subtle);
}

.Avatar--small { width: var(--space-6); height: var(--space-6); }
.Avatar--large { width: var(--space-12); height: var(--space-12); }

/* Cards */
.Card {
  background-color: var(--bg-primary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--space-2);
  overflow: hidden;
  transition: transform 0.2s, box-shadow 0.2s;
  display: flex;
  flex-direction: column;
}

.Card--interactive:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px oklch(0% 0 0 / 0.05);
  border-color: var(--border-strong);
}

.Card-image {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background-color: var(--bg-secondary);
}

.Card-body {
  padding: var(--space-4);
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.Card-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
}

.Card-description {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.Card-footer {
  padding: var(--space-3) var(--space-4);
  border-top: 1px solid var(--border-subtle);
  background-color: var(--bg-secondary);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

/* Tables */
.Table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-4) 0;
  font-size: 0.9rem;
}

.Table th {
  text-align: left;
  padding: var(--space-3) var(--space-4);
  background-color: var(--bg-secondary);
  color: var(--text-secondary);
  font-weight: 600;
  text-transform: uppercase;
  font-size: 0.75rem;
  letter-spacing: 0.05em;
  border-bottom: 2px solid var(--border-subtle);
}

.Table td {
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-primary);
}

.Table tbody tr:hover {
  background-color: oklch(0% 0 0 / 0.02);
}

.Table--bordered {
  border: 1px solid var(--border-subtle);
}

.Table--bordered td, .Table--bordered th {
  border: 1px solid var(--border-subtle);
}

/* Modals */
.Modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: oklch(0% 0 0 / 0.4);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: all 0.2s ease;
}

.Modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.Modal {
  background-color: var(--bg-primary);
  border-radius: var(--space-3);
  width: 100%;
  max-width: 480px;
  box-shadow: 0 20px 40px oklch(0% 0 0 / 0.2);
  transform: translateY(20px);
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  display: flex;
  flex-direction: column;
}

.Modal-overlay.active .Modal {
  transform: translateY(0);
}

.Modal-header {
  padding: var(--space-4) var(--space-6);
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.Modal-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.Modal-body {
  padding: var(--space-6);
  color: var(--text-secondary);
}

.Modal-footer {
  padding: var(--space-4) var(--space-6);
  border-top: 1px solid var(--border-subtle);
  display: flex;
  justify-content: flex-end;
  gap: var(--space-3);
}