/* DevTools Field Guide - Nervous System Light Theme */
/* DESN378 palette adapted for light documentation */

:root {
  /* Nervous System Light - DESN378 palette */
  --bg: #f8fafc;
  --bg-sidebar: #ffffff;
  --text: #1a1a1a;
  --text-muted: #6b7280;
  --text-light: #9ca3af;
  --border: #e2e8f0;

  /* Primary: Teal */
  --accent: #01B799;
  --accent-light: rgba(1, 183, 153, 0.15);
  --accent-hover: #019a80;

  /* Links: Cyan */
  --link: #22D3EE;
  --link-hover: #06B6D4;

  /* Special: Violet */
  --violet: #A855F7;
  --violet-light: rgba(168, 85, 247, 0.15);

  /* Component colors */
  --code-bg: #f1f5f9;
  --warning-bg: #fef3c7;
  --warning-border: #f59e0b;
  --success-bg: rgba(1, 183, 153, 0.12);
  --success-border: #01B799;
  --error-bg: #fee2e2;
  --error-border: #ef4444;

  /* Layout */
  --sidebar-width: 260px;
  --toc-width: 200px;
  --content-max: 720px;
  --header-height: 56px;
  --layout-max: 1300px;
}

/* ========== Base Styles ========== */

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

body {
  font-family: 'DM Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  font-size: 15px;
}

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

.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background: var(--bg-sidebar);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  padding: 0 24px;
  z-index: 100;
  max-width: var(--layout-max);
  margin-left: auto;
  margin-right: auto;
}

.header-logo {
  font-weight: 600;
  font-size: 16px;
  color: var(--text);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 10px;
}

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

.header-nav {
  display: flex;
  gap: 8px;
  margin-left: 32px;
}

.header-nav a {
  padding: 8px 14px;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  border-radius: 6px;
  transition: all 0.15s ease;
}

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

.header-nav a.active {
  color: var(--accent);
  background: var(--accent-light);
}

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

.layout {
  display: flex;
  padding-top: var(--header-height);
  min-height: 100vh;
  max-width: var(--layout-max);
  margin: 0 auto;
}

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

.sidebar {
  position: fixed;
  top: var(--header-height);
  left: max(0px, calc((100vw - var(--layout-max)) / 2));
  width: var(--sidebar-width);
  height: calc(100vh - var(--header-height));
  background: var(--bg-sidebar);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  padding: 20px 0;
}

.sidebar-section {
  margin-bottom: 24px;
}

.sidebar-title {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  padding: 8px 24px;
}

.sidebar-link {
  display: block;
  padding: 8px 24px;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 14px;
  border-left: 2px solid transparent;
  transition: all 0.15s ease;
}

.sidebar-link:hover {
  color: var(--text);
  background: var(--code-bg);
}

.sidebar-link.active {
  color: var(--accent);
  border-left-color: var(--accent);
  background: var(--accent-light);
  font-weight: 500;
}

.sidebar-link.indent {
  padding-left: 40px;
  font-size: 13px;
}

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

.main {
  flex: 1;
  margin-left: var(--sidebar-width);
  margin-right: var(--toc-width);
  padding: 40px 60px;
  max-width: calc(var(--layout-max) - var(--sidebar-width) - var(--toc-width));
}

/* ========== Breadcrumb ========== */

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.breadcrumb a {
  color: var(--link);
  text-decoration: none;
}

.breadcrumb a:hover {
  color: var(--link-hover);
  text-decoration: underline;
}

.breadcrumb-sep {
  color: var(--text-light);
}

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

h1 {
  font-size: 36px;
  font-weight: 600;
  line-height: 1.2;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 24px;
  font-weight: 600;
  margin-top: 48px;
  margin-bottom: 16px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  letter-spacing: -0.01em;
}

h2:first-of-type {
  margin-top: 32px;
  border-top: none;
  padding-top: 0;
}

h3 {
  font-size: 18px;
  font-weight: 600;
  margin-top: 32px;
  margin-bottom: 12px;
}

p {
  margin-bottom: 16px;
  color: var(--text);
}

.lead {
  font-size: 17px;
  color: var(--text-muted);
  margin-bottom: 32px;
}

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

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

ul, ol {
  margin: 16px 0;
  padding-left: 24px;
}

li {
  margin-bottom: 8px;
}

/* ========== Code ========== */

code {
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
  background: var(--code-bg);
  padding: 2px 6px;
  border-radius: 4px;
}

pre {
  background: #1e293b;
  color: #e2e8f0;
  padding: 20px 24px;
  border-radius: 8px;
  overflow-x: auto;
  margin: 20px 0;
  font-size: 13px;
  line-height: 1.7;
}

pre code {
  background: none;
  padding: 0;
  color: inherit;
}

/* Syntax highlighting */
.code-comment { color: #64748b; }
.code-keyword { color: #A855F7; }
.code-string { color: #01B799; }
.code-property { color: #22D3EE; }
.code-result { color: #94a3b8; font-style: italic; }
.code-error { color: #fca5a5; }

/* ========== Callouts ========== */

.callout {
  padding: 16px 20px;
  border-radius: 8px;
  margin: 24px 0;
  border-left: 4px solid;
}

.callout-note {
  background: var(--accent-light);
  border-color: var(--accent);
}

.callout-warning {
  background: var(--warning-bg);
  border-color: var(--warning-border);
}

.callout-success {
  background: var(--success-bg);
  border-color: var(--success-border);
}

.callout-error {
  background: var(--error-bg);
  border-color: var(--error-border);
}

.callout-title {
  font-weight: 600;
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 8px;
}

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

/* ========== Exercise Blocks ========== */

.exercise {
  background: linear-gradient(135deg, rgba(1, 183, 153, 0.08) 0%, rgba(1, 183, 153, 0.12) 100%);
  border: 1px solid rgba(1, 183, 153, 0.3);
  border-radius: 12px;
  padding: 24px;
  margin: 24px 0;
}

.exercise-title {
  font-weight: 600;
  font-size: 14px;
  color: var(--accent);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.exercise ol {
  margin: 0;
  padding-left: 20px;
}

.exercise li {
  color: var(--accent-hover);
}

/* ========== Metaphor Blocks ========== */

.metaphor {
  background: linear-gradient(135deg, rgba(168, 85, 247, 0.08) 0%, rgba(168, 85, 247, 0.12) 100%);
  border: 1px solid rgba(168, 85, 247, 0.3);
  border-radius: 12px;
  padding: 24px;
  margin: 24px 0;
}

.metaphor-title {
  font-weight: 600;
  font-size: 14px;
  color: var(--violet);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.metaphor p {
  color: #7c3aed;
  margin-bottom: 0;
}

/* ========== Keyboard Keys ========== */

kbd {
  display: inline-block;
  padding: 3px 8px;
  font-family: 'JetBrains Mono', monospace;
  font-size: 12px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  box-shadow: 0 1px 2px rgba(0,0,0,0.05);
}

/* ========== Tables ========== */

table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  font-size: 14px;
}

th, td {
  padding: 12px 16px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

th {
  font-weight: 600;
  background: var(--code-bg);
}

/* ========== Concept/Feature Cards ========== */

.concept-grid,
.feature-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin: 24px 0;
}

.concept-card,
.feature-card {
  background: var(--bg-sidebar);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
  transition: all 0.2s ease;
}

.concept-card:hover,
.feature-card:hover {
  border-color: var(--accent);
  box-shadow: 0 4px 12px rgba(1, 183, 153, 0.15);
}

.concept-card h4,
.feature-card h4 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 8px;
}

.concept-card p,
.feature-card p {
  font-size: 13px;
  color: var(--text-muted);
  margin: 0;
}

/* ========== Step Cards ========== */

.step-cards {
  display: grid;
  gap: 16px;
  margin: 24px 0;
}

.step-card {
  display: flex;
  gap: 16px;
  background: var(--bg-sidebar);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
}

.step-number {
  width: 32px;
  height: 32px;
  background: var(--accent);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 14px;
  flex-shrink: 0;
}

.step-content h4 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 4px;
}

.step-content p {
  font-size: 14px;
  color: var(--text-muted);
  margin: 0;
}

.step-content code {
  font-size: 12px;
}

/* ========== Diagrams ========== */

.diagram {
  background: var(--bg-sidebar);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 32px;
  margin: 24px 0;
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
  line-height: 1.8;
  overflow-x: auto;
}

.diagram-label {
  color: var(--link);
  font-weight: 500;
}

.diagram-arrow {
  color: var(--text-light);
}

/* ========== Bridge Visualization ========== */

.bridge-visual {
  background: linear-gradient(135deg, rgba(34, 211, 238, 0.1) 0%, rgba(1, 183, 153, 0.15) 100%);
  border: 1px solid rgba(34, 211, 238, 0.3);
  border-radius: 16px;
  padding: 32px;
  margin: 32px 0;
  text-align: center;
}

.bridge-panels {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 24px;
  margin-bottom: 24px;
}

.bridge-panel {
  background: white;
  border-radius: 12px;
  padding: 20px 24px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.08);
  min-width: 160px;
}

.bridge-panel-title {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.bridge-panel-content {
  font-family: 'JetBrains Mono', monospace;
  font-size: 14px;
  color: var(--text);
}

.bridge-arrow {
  font-size: 32px;
  color: var(--accent);
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 0.5; transform: scale(1); }
  50% { opacity: 1; transform: scale(1.1); }
}

.bridge-label {
  font-size: 18px;
  font-weight: 600;
  color: var(--accent);
  margin-top: 16px;
}

.bridge-sublabel {
  font-size: 14px;
  color: var(--text-muted);
}

/* ========== Console Simulation ========== */

.console-demo {
  background: #1e293b;
  border-radius: 12px;
  overflow: hidden;
  margin: 24px 0;
  font-family: 'JetBrains Mono', monospace;
  font-size: 13px;
}

.console-header {
  background: #334155;
  padding: 8px 16px;
  display: flex;
  gap: 8px;
  align-items: center;
}

.console-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}

.console-dot.red { background: #ef4444; }
.console-dot.yellow { background: #eab308; }
.console-dot.green { background: #22c55e; }

.console-tab {
  margin-left: 16px;
  padding: 4px 12px;
  background: #1e293b;
  color: #94a3b8;
  border-radius: 4px 4px 0 0;
  font-size: 11px;
}

.console-body {
  padding: 16px;
  color: #e2e8f0;
}

.console-line {
  display: flex;
  align-items: flex-start;
  margin-bottom: 8px;
}

.console-prompt {
  color: #60a5fa;
  margin-right: 8px;
  user-select: none;
}

.console-output { color: #94a3b8; }
.console-log { color: #e2e8f0; }
.console-error { color: #fca5a5; }
.console-warn { color: #fcd34d; }
.console-object { color: #22D3EE; }

.message-type {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 11px;
  font-weight: 600;
  margin-right: 8px;
}

.message-type.log { background: #334155; color: #94a3b8; }
.message-type.error { background: #7f1d1d; color: #fca5a5; }
.message-type.warn { background: #713f12; color: #fcd34d; }
.message-type.info { background: #1e3a5f; color: #7dd3fc; }

/* ========== Badges ========== */

.badge {
  display: inline-block;
  padding: 2px 8px;
  font-size: 11px;
  font-weight: 600;
  border-radius: 4px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.badge-flex { background: rgba(168, 85, 247, 0.15); color: #A855F7; }
.badge-grid { background: rgba(34, 211, 238, 0.15); color: #22D3EE; }
.badge-scroll { background: rgba(1, 183, 153, 0.15); color: #01B799; }
.badge-new { background: #fef3c7; color: #b45309; }

/* ========== Compare Table ========== */

.compare-table {
  margin: 24px 0;
}

.compare-table th:first-child {
  width: 40%;
}

.compare-table .skip {
  color: var(--text-light);
  font-style: italic;
}

.compare-table .keep {
  color: #166534;
  font-weight: 500;
}

/* ========== Table of Contents ========== */

.toc {
  position: fixed;
  top: var(--header-height);
  right: max(0px, calc((100vw - var(--layout-max)) / 2));
  width: var(--toc-width);
  height: calc(100vh - var(--header-height));
  padding: 32px 20px;
  overflow-y: auto;
  border-left: 1px solid var(--border);
  background: var(--bg);
}

.toc-title {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 12px;
}

.toc-link {
  display: block;
  padding: 6px 0;
  font-size: 13px;
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.15s ease;
}

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

.toc-link.active {
  color: var(--accent);
  font-weight: 500;
}

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

@media (max-width: 1200px) {
  .toc {
    display: none;
  }
  .main {
    margin-right: 0;
  }
}

@media (max-width: 900px) {
  .sidebar {
    display: none;
  }
  .main {
    margin-left: 0;
    padding: 24px;
  }
  .bridge-panels {
    flex-direction: column;
  }
  .bridge-arrow {
    transform: rotate(90deg);
  }
  .concept-grid,
  .feature-grid {
    grid-template-columns: 1fr;
  }
}

/* ========== Page Navigation (Primer-style) ========== */

.page-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  gap: 16px;
}

.page-nav-link {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 16px 20px;
  background: var(--bg-sidebar);
  border: 1px solid var(--border);
  border-radius: 8px;
  text-decoration: none;
  transition: all 0.15s ease;
  min-width: 180px;
}

.page-nav-link:hover {
  border-color: var(--accent);
  box-shadow: 0 2px 8px rgba(1, 183, 153, 0.15);
  text-decoration: none;
}

.page-nav-prev {
  align-items: flex-start;
}

.page-nav-next {
  align-items: flex-end;
  margin-left: auto;
}

.page-nav-label {
  font-size: 12px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.page-nav-title {
  font-size: 15px;
  font-weight: 500;
  color: var(--accent);
}

.page-nav-link:hover .page-nav-title {
  color: var(--accent-hover);
}

/* When only one direction available */
.page-nav-link:only-child.page-nav-next {
  margin-left: auto;
}

@media (max-width: 600px) {
  .page-nav {
    flex-direction: column;
  }
  .page-nav-link {
    width: 100%;
  }
  .page-nav-prev,
  .page-nav-next {
    align-items: flex-start;
  }
}