:root {
  --bg-canvas: hsl(216, 24%, 9%);
  --bg-surface: hsl(216, 21%, 12%);
  --bg-elevated: hsl(216, 19%, 15%);
  --bg-code: hsl(218, 26%, 8%);
  --bg-interactive: hsl(215, 18%, 18%);

  --border-subtle: hsl(215, 16%, 19%);
  --border-strong: hsl(215, 16%, 26%);

  --text-primary: hsl(210, 24%, 95%);
  --text-secondary: hsl(214, 15%, 72%);
  --text-muted: hsl(215, 13%, 54%);

  --accent-blue: hsl(208, 88%, 62%);
  --accent-blue-bg: hsla(208, 88%, 62%, 0.12);
  --accent-amber: hsl(37, 92%, 58%);
  --accent-amber-bg: hsla(37, 92%, 58%, 0.14);
  --accent-green: hsl(152, 65%, 52%);
  --accent-green-bg: hsla(152, 65%, 52%, 0.12);
  --accent-teal: hsl(184, 70%, 54%);
  --accent-teal-bg: hsla(184, 70%, 54%, 0.12);

  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
}

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

html, body {
  margin: 0;
  padding: 0;
  background-color: var(--bg-canvas);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--accent-blue);
  text-decoration: none;
  transition: color 0.15s ease;
}

a:hover {
  color: hsl(208, 95%, 74%);
}

code, pre {
  font-family: var(--font-mono);
}

p code, li code, td code {
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  padding: 0.12rem 0.38rem;
  border-radius: 4px;
  font-size: 0.86em;
  color: hsl(204, 80%, 82%);
}

/* Header & Navigation */
.site-header {
  border-bottom: 1px solid var(--border-subtle);
  background: var(--bg-surface);
  position: sticky;
  top: 0;
  z-index: 50;
}

.header-inner {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0.85rem 1.75rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--text-primary);
  font-weight: 600;
  font-size: 1rem;
}

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

.brand-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 30px;
  height: 30px;
  border-radius: var(--radius-sm);
  background: var(--accent-blue-bg);
  border: 1px solid hsla(208, 88%, 62%, 0.35);
  color: var(--accent-blue);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.85rem;
}

.header-nav {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.nav-pill {
  padding: 0.4rem 0.75rem;
  border-radius: var(--radius-sm);
  font-size: 0.84rem;
  font-weight: 500;
  color: var(--text-secondary);
  border: 1px solid transparent;
  transition: all 0.15s ease;
}

.nav-pill:hover {
  color: var(--text-primary);
  background: var(--bg-elevated);
  border-color: var(--border-subtle);
}

.nav-pill.active {
  color: var(--accent-blue);
  background: var(--accent-blue-bg);
  border-color: hsla(208, 88%, 62%, 0.35);
}

.nav-pill.bug-link {
  color: var(--accent-amber);
  background: var(--accent-amber-bg);
  border-color: hsla(37, 92%, 58%, 0.35);
}

.other-things {
  margin-top: 0.85rem;
  font-size: 0.87rem;
}

.other-things summary {
  cursor: pointer;
  font-weight: 600;
  color: var(--text-secondary);
}

.other-things .check-list {
  margin-top: 0.5rem;
  border-top: none;
  padding-left: 1.5rem;
}

.triage-hint {
  margin: 0.85rem 0 0;
  font-size: 0.84rem;
  color: var(--text-muted);
}

/* Containers */
.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 2.25rem 1.75rem 4rem;
}

/* Hero Section */
.hero {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 2.25rem 2.5rem;
  margin-bottom: 2.25rem;
}

.hero-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent-amber);
  margin-bottom: 0.65rem;
  display: block;
}

.hero h1 {
  font-size: clamp(1.75rem, 3vw, 2.35rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin: 0 0 0.85rem;
  line-height: 1.2;
}

.hero-lead {
  color: var(--text-secondary);
  font-size: 1.04rem;
  max-width: 860px;
  margin: 0 0 1.5rem;
}

.prereq-banner {
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  border-left: 3px solid var(--accent-blue);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1rem;
}

.prereq-item strong {
  display: block;
  font-size: 0.84rem;
  color: var(--text-primary);
  margin-bottom: 0.2rem;
}

.prereq-item span {
  font-size: 0.84rem;
  color: var(--text-secondary);
}

/* Feature Tags */
.capability-tag {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  font-weight: 600;
  padding: 0.18rem 0.5rem;
  border-radius: 4px;
  display: inline-block;
  margin-bottom: 0.55rem;
}

.tag-stack {
  background: var(--accent-amber-bg);
  color: var(--accent-amber);
}

.tag-scope {
  background: var(--accent-blue-bg);
  color: var(--accent-blue);
}

.tag-hints {
  background: var(--accent-teal-bg);
  color: var(--accent-teal);
}

.tag-eval {
  background: var(--accent-green-bg);
  color: var(--accent-green);
}

.tag-auto {
  background: hsla(198, 90%, 60%, 0.14);
  color: hsl(198, 92%, 68%);
}

.tag-bp {
  background: hsla(14, 88%, 60%, 0.14);
  color: hsl(14, 92%, 68%);
}

/* Examples Cards Grid on Index */
.section-heading {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 1.1rem;
}

.section-heading h2 {
  margin: 0;
  font-size: 1.3rem;
  letter-spacing: -0.01em;
}

.examples-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
}

@media (max-width: 920px) {
  .examples-grid {
    grid-template-columns: 1fr;
  }
}

.example-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.5rem 1.65rem;
  display: flex;
  flex-direction: column;
  transition: transform 0.16s ease, border-color 0.16s ease, background-color 0.16s ease;
}

.example-card:hover {
  transform: translateY(-2px);
  border-color: var(--accent-blue);
  background: hsl(216, 21%, 13.5%);
}

.example-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.75rem;
}

.example-num {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--accent-blue);
  background: var(--accent-blue-bg);
  padding: 0.2rem 0.55rem;
  border-radius: 4px;
}

.example-card h3 {
  margin: 0 0 0.5rem;
  font-size: 1.18rem;
  color: var(--text-primary);
}

.example-card p {
  margin: 0 0 1.15rem;
  color: var(--text-secondary);
  font-size: 0.92rem;
}

.chip-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 1.25rem;
}

.chip {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
}

.example-card .chip-list {
  margin-top: auto;
  margin-bottom: 0;
}

.example-card .capability-tag {
  margin-bottom: 0;
}

/* Example Detail Page Layout */
.example-header-bar {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.65rem 2rem;
  margin-bottom: 1.5rem;
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.example-title-block {
  max-width: 780px;
}

.example-title-block h1 {
  margin: 0.35rem 0 0.5rem;
  font-size: 1.65rem;
  letter-spacing: -0.02em;
}

.example-title-block p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.98rem;
}

.action-panel {
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  padding: 1.1rem 1.25rem;
  min-width: 330px;
  flex: 1;
  max-width: 440px;
}

.action-buttons {
  display: flex;
  gap: 0.65rem;
  flex-wrap: wrap;
  margin-bottom: 0.75rem;
}

.btn-primary {
  appearance: none;
  border: 1px solid hsla(37, 92%, 58%, 0.45);
  background: linear-gradient(180deg, hsl(37, 90%, 52%), hsl(34, 88%, 44%));
  color: hsl(216, 28%, 8%);
  font-family: var(--font-sans);
  font-weight: 700;
  font-size: 0.9rem;
  padding: 0.62rem 1.1rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  transition: filter 0.15s ease, transform 0.1s ease;
}

.btn-primary:hover {
  filter: brightness(1.08);
}

.btn-primary:active {
  transform: translateY(1px);
}

.btn-secondary {
  appearance: none;
  border: 1px solid var(--border-strong);
  background: var(--bg-surface);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 0.85rem;
  padding: 0.58rem 0.95rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background-color 0.15s ease, border-color 0.15s ease;
}

.btn-secondary:hover {
  background: var(--bg-interactive);
  border-color: var(--accent-blue);
}

.output-readout {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  background: var(--bg-code);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.6rem 0.75rem;
  color: var(--accent-green);
  overflow-x: auto;
  white-space: pre-wrap;
  word-break: break-word;
}

/* Workbench Split Grid */
.workbench-grid {
  display: grid;
  grid-template-columns: 5fr 6fr;
  gap: 1.5rem;
  align-items: start;
}

@media (max-width: 1120px) {
  .workbench-grid {
    grid-template-columns: 1fr;
  }
}

.panel-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.4rem 1.6rem;
  margin-bottom: 1.25rem;
}

.panel-card h2 {
  margin: 0 0 0.85rem;
  font-size: 1.12rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* What to Try & Verify Cards */
.steps-list {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.step-item {
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 0.95rem 1.15rem;
  transition: border-color 0.15s ease, opacity 0.15s ease;
}

.step-item:hover {
  border-color: var(--border-strong);
}

.step-item.checked {
  opacity: 0.62;
  border-color: hsla(152, 65%, 52%, 0.35);
}

.step-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.65rem;
  margin-bottom: 0.45rem;
}

.step-num-title {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  font-weight: 600;
  font-size: 0.94rem;
  cursor: pointer;
}

.step-checkbox {
  width: 16px;
  height: 16px;
  accent-color: var(--accent-green);
  cursor: pointer;
  margin: 0;
  flex-shrink: 0;
}

.try-prompt {
  font-size: 0.87rem;
  color: var(--text-primary);
  margin: 0 0 0.5rem;
  padding-left: 1.55rem;
}

.try-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--accent-amber);
  margin-right: 0.35rem;
}

.check-list {
  margin: 0;
  padding: 0.45rem 0 0 2.55rem;
  border-top: 1px dashed var(--border-subtle);
  font-size: 0.84rem;
  color: var(--text-secondary);
  display: flex;
  flex-direction: column;
  gap: 0.28rem;
}

.check-list li strong {
  color: var(--text-primary);
}

/* Console Debug Evaluate Table */
.eval-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.eval-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 0.85rem 1rem;
}

.eval-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  background: var(--bg-code);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.45rem 0.7rem;
  margin-bottom: 0.5rem;
}

.eval-expr {
  font-family: var(--font-mono);
  font-size: 0.83rem;
  color: hsl(42, 95%, 72%);
  overflow-x: auto;
}

.btn-copy {
  appearance: none;
  background: var(--bg-elevated);
  border: 1px solid var(--border-strong);
  color: var(--text-secondary);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 0.22rem 0.55rem;
  border-radius: 4px;
  cursor: pointer;
  flex-shrink: 0;
}

.btn-copy:hover {
  color: var(--text-primary);
  border-color: var(--accent-blue);
}

.eval-meta {
  font-size: 0.82rem;
  color: var(--text-secondary);
}

.eval-result {
  font-family: var(--font-mono);
  color: var(--accent-green);
  font-weight: 600;
}

/* Code & SourceMap Tabbed Inspector */
.inspector-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
  position: sticky;
  top: 4.5rem;
}

.tabs-bar {
  display: flex;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border-subtle);
  overflow-x: auto;
}

.tab-btn {
  appearance: none;
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  color: var(--text-secondary);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.85rem 1.1rem;
  cursor: pointer;
  white-space: nowrap;
  transition: color 0.15s ease, background-color 0.15s ease;
}

.tab-btn:hover {
  color: var(--text-primary);
  background: hsla(215, 18%, 24%, 0.4);
}

.tab-btn.active {
  color: var(--accent-blue);
  border-bottom-color: var(--accent-blue);
  background: var(--bg-surface);
}

.tab-pane {
  display: none;
}

.tab-pane.active {
  display: block;
}

.code-block-wrapper {
  background: var(--bg-code);
  padding: 1rem 0;
  overflow-x: auto;
  max-height: 700px;
  overflow-y: auto;
}

.code-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.55;
}

.code-line-row:hover {
  background: hsla(210, 30%, 20%, 0.28);
}

.code-line-row.debugger-line {
  background: hsla(37, 92%, 58%, 0.14);
}

.code-line-num {
  user-select: none;
  text-align: right;
  padding: 0 0.85rem 0 1rem;
  color: var(--text-muted);
  width: 1%;
  white-space: nowrap;
  border-right: 1px solid var(--border-subtle);
}

.code-line-text {
  padding: 0 1.25rem;
  white-space: pre;
  color: hsl(210, 22%, 90%);
}

/* Scope Tree Visualizer inside Tab 4 */
.tree-section {
  padding: 1.25rem 1.4rem;
  border-bottom: 1px solid var(--border-subtle);
}

.tree-section h3 {
  margin: 0 0 0.65rem;
  font-size: 0.92rem;
  font-family: var(--font-mono);
  color: var(--accent-blue);
}

.scope-tree-node {
  margin-left: 1.1rem;
  padding: 0.45rem 0.65rem;
  border-left: 2px solid var(--border-strong);
  margin-top: 0.4rem;
  background: var(--bg-elevated);
  border-radius: 0 6px 6px 0;
  font-family: var(--font-mono);
  font-size: 0.78rem;
}

.node-badge {
  display: inline-block;
  padding: 0.1rem 0.4rem;
  border-radius: 3px;
  font-weight: 700;
  font-size: 0.72rem;
  margin-right: 0.4rem;
}