/* LF Audio Help Center — matches lf-audio.com Shopify store */

:root {
  --color-bg: #ffffff;
  --color-text: #444444;
  --color-heading: #111111;
  /* Brand + semantic tokens — synced with app-portal/style.css,
     admin/theme.css, and the AuralSync mobile app (lib/constants.dart
     → AppColors + lib/main.dart). Theme-token changes here MUST flow
     to all four projects. See repo CLAUDE.md "Theme sync". */
  --color-accent: #0891b2;
  --color-accent-light: #cffafe;
  /* Near-black foreground that clears AA (>= 4.5:1) on BOTH the light
     accent (#0891b2) and the dark accent (#00d3f3), so filled-accent
     buttons don't need per-theme overrides. */
  --color-accent-contrast: #0c1429;
  --color-border: #e5e7eb;
  --color-surface: #f9fafb;
  --color-surface-alt: #f1f3f7;
  --color-muted: #6b7280;
  --color-success: #16a34a;
  --color-success-bg: #dcfce7;
  --color-warning: #d97706;
  --color-warning-bg: #fef3c7;
  --color-danger: #dc2626;
  --color-danger-bg: #fee2e2;
  --color-info: #2563eb;
  --color-info-bg: #dbeafe;
  --color-purple: #9333ea;
  --color-purple-bg: #f3e8ff;
  --font-family: "Instrument Sans", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;

  /* Type scale — synced across admin/theme.css, app-portal/style.css,
     and the AuralSync mobile app (lib/constants.dart → AppTypography).
     Existing inline font-size values are NOT migrated en masse; new code
     SHOULD prefer these. */
  --font-size-xs: 11px;
  --font-size-sm: 12px;
  --font-size-base: 14px;
  --font-size-md: 16px;
  --font-size-lg: 18px;
  --font-size-xl: 20px;
  --font-size-2xl: 24px;
  --font-size-3xl: 32px;

  /* Spacing scale — synced with the three other LF Audio projects.
     Use in place of bare px values for paddings/margins/gaps. */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 12px;
  --space-lg: 16px;
  --space-xl: 24px;
  --space-2xl: 32px;
  --space-3xl: 48px;

  --radius: 12px;
  --radius-sm: 8px;
  --radius-large: 16px;
  --radius-pill: 999px;

  /* Shadow scale — synced with admin/theme.css's --lf-shadow / --lf-shadow-lg
     (admin keeps both names via an alias). App-portal mirrors these
     identical values. Mobile is intentionally border-only (no elevation)
     by design — see CLAUDE.md "Theme sync". */
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 40px rgba(0, 0, 0, 0.1);

  --max-width: 1440px;
  --sidebar-width: 260px;
}

/* --- Dark theme --- */
[data-theme="dark"] {
  --color-bg: #1a1a2e;
  --color-text: #d1d5db;
  --color-heading: #f3f4f6;
  --color-accent: #00d3f3;
  --color-accent-light: #164e63;
  /* Bumped from #2d2d44 (1.28:1 vs page) to improve card-boundary
     perception per WCAG 1.4.11. Still below strict 3:1 but a clear
     improvement without lighting up the "ghost card" aesthetic. */
  --color-border: #3d3d5e;
  --color-surface: #22223a;
  --color-surface-alt: #2a2a45;
  --color-muted: #9ca3af;
  --color-success: #34d399;
  --color-success-bg: #103828;
  --color-warning: #f59e0b;
  --color-warning-bg: #3d2a0a;
  --color-danger: #f87171;
  --color-danger-bg: #3d1d1d;
  /* Lightened from #6b8cff to gain contrast headroom against info-bg
     for small labels (4.6:1 → 5.85:1). */
  --color-info: #8aa2ff;
  --color-info-bg: #1e2a4a;
  --color-purple: #caa4ff;
  --color-purple-bg: #3a1f4d;

  /* Dark-theme shadow values mirror admin/theme.css. */
  --shadow: 0 1px 3px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 10px 40px rgba(0, 0, 0, 0.5);
}

/* Respect user preference for reduced motion — disables card hover lifts,
 * loading-dot animation, chevron rotations, etc. WCAG 2.3.3. */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* Scrollbars — tinted to the theme palette so the default bright-white
 * browser scrollbar doesn't drift visually on dark surfaces. Transparent
 * track lets the underlying page/panel color show through. */
* {
  scrollbar-width: thin;
  scrollbar-color: var(--color-border) transparent;
}
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}
::-webkit-scrollbar-track {
  background: transparent;
}
::-webkit-scrollbar-thumb {
  background: var(--color-border);
  border-radius: 5px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--color-muted);
}
::-webkit-scrollbar-corner {
  background: transparent;
}
[data-theme="dark"] .search-dialog { background: var(--color-surface); }
[data-theme="dark"] .search-trigger { background: var(--color-surface); border-color: var(--color-border); }
[data-theme="dark"] .search-input-wrapper kbd { background: var(--color-surface-alt); border-color: var(--color-border); }

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

body {
  font-family: var(--font-family);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--color-accent); text-decoration: underline; }
a:hover { color: var(--color-accent); text-decoration: none; }

/* Global focus ring — synced with app-portal + admin. Uses :focus-visible
 * so mouse clicks don't get the outline, only keyboard navigation does.
 * Theme-sync rule: mirrored in app-portal/style.css + admin/theme.css. */
:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: 4px;
}

/* --- Header --- */
.site-header {
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg);
  position: sticky;
  top: 0;
  z-index: 100;
}
.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.75rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.logo-link {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--color-heading);
  font-weight: 600;
  font-size: 1.1rem;
  white-space: nowrap;
  text-decoration: none;
}
.logo-link:hover { text-decoration: none; color: var(--color-heading); }
.logo-img { height: 18px; width: auto; }
.logo-divider { color: var(--color-border); font-weight: 300; }
.logo-sub { color: var(--color-muted); font-weight: 400; }

/* --- Search trigger --- */
.search-trigger {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: 30px;
  background: var(--color-surface);
  color: var(--color-muted);
  font-family: var(--font-family);
  font-size: 0.875rem;
  cursor: pointer;
  transition: border-color 0.15s;
  min-width: 200px;
}
.search-trigger:hover { border-color: var(--color-accent); }
.search-trigger kbd {
  margin-left: auto;
  padding: 0.15rem 0.4rem;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  font-size: 0.75rem;
  background: var(--color-bg);
}

/* --- Nav bar (removed — navigation in sidebar) --- */

/* --- Page layout --- */
.page-layout {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  min-height: calc(100vh - 200px);
}

/* --- Sidebar --- */
.sidebar {
  width: var(--sidebar-width);
  flex-shrink: 0;
  border-right: 1px solid var(--color-border);
  padding: 1.25rem 0.75rem 2rem 0.75rem;
  overflow-y: auto;
  max-height: calc(100vh - 60px);
  position: sticky;
  top: 60px;
}
.sidebar-inner { }
.sidebar-collection { margin-bottom: 0.25rem; }
.sidebar-collection-title {
  font-size: 0.95rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--color-muted);
  margin-bottom: 0;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.25rem;
  padding: 0.35rem 0.25rem;
  border-radius: var(--radius-sm);
  transition: background 0.1s;
}
.sidebar-collection-title:hover { background: var(--color-surface-alt); }
.sidebar-collection-title a {
  color: var(--color-muted);
  text-decoration: none;
  flex: 1;
}
.sidebar-collection-title a:hover {
  color: var(--color-heading);
  text-decoration: none;
}
.sidebar-collection.open > .sidebar-collection-title a {
  color: var(--color-heading);
}

/* Chevron arrows */
.chevron {
  display: inline-block;
  width: 0;
  height: 0;
  border-left: 4px solid transparent;
  border-right: 4px solid transparent;
  border-top: 5px solid var(--color-muted);
  transition: transform 0.15s;
  transform: rotate(-90deg);
  flex-shrink: 0;
}
.open > .sidebar-collection-title > .chevron,
.sidebar-section.open > .sidebar-section-title > .chevron {
  transform: rotate(0deg);
}

/* Collapse/expand body */
.sidebar-collection-body {
  display: none;
  padding-left: 0.25rem;
}
.sidebar-collection.open > .sidebar-collection-body {
  display: block;
}

.sidebar-section { margin-bottom: 0.25rem; margin-left: 0.5rem; }
.sidebar-section > ul {
  display: none;
}
.sidebar-section.open > ul {
  display: block;
}
.sidebar-section-title {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-heading);
  margin-bottom: 0.15rem;
  padding: 0.2rem 0.5rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.3rem;
  border-radius: var(--radius-sm);
  transition: background 0.1s;
}
.sidebar-section-title:hover { background: var(--color-surface-alt); }
.sidebar-section ul { list-style: none; padding-left: 0.5rem; }
.sidebar-section li { margin-bottom: 0.1rem; }
.sidebar-section li a {
  display: block;
  padding: 0.25rem 0.5rem;
  border-radius: var(--radius-sm);
  color: var(--color-text);
  font-size: 0.825rem;
  transition: background 0.1s;
  text-decoration: none;
}
.sidebar-section li a:hover {
  background: var(--color-surface-alt);
  text-decoration: none;
}
.sidebar-section li.active a {
  background: var(--color-accent-light);
  color: var(--color-accent);
  font-weight: 500;
}

/* --- Main content --- */
.main-content {
  flex: 1;
  min-width: 0;
  padding: 1.5rem 2rem 3rem;
}

/* --- Breadcrumb --- */
.breadcrumb {
  font-size: 0.85rem;
  color: var(--color-muted);
  margin-bottom: 1.5rem;
}
.breadcrumb a { color: var(--color-muted); }
.breadcrumb a:hover { color: var(--color-accent); }
.breadcrumb span { margin: 0 0.35rem; }

/* --- Article --- */
.article-header { margin-bottom: 2rem; }
.article-header h1 {
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-heading);
  line-height: 1.2;
  margin-bottom: 0.5rem;
}
.article-body h2 {
  font-size: 1.4rem;
  font-weight: 600;
  color: var(--color-heading);
  margin: 1.5rem 0 0.5rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--color-border);
}
.article-body h3 {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--color-heading);
  margin: 1rem 0 0.35rem;
}
.article-body p { margin-bottom: 0.65rem; }
.article-body ul, .article-body ol {
  margin: 0 0 0.65rem 1.5rem;
}
.article-body li { margin-bottom: 0.2rem; }
.article-body img {
  max-width: 100%;
  border-radius: var(--radius-sm);
  margin: 1rem 0;
}
.article-body hr {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: 1.25rem 0;
}

/* --- Tables --- */
.article-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0 1.5rem;
  font-size: 0.9rem;
  table-layout: auto;
}
.article-body th, .article-body td {
  padding: 0.6rem 0.75rem;
  text-align: left;
  border: 1px solid var(--color-border);
}
.article-body th:first-child, .article-body td:first-child {
  white-space: nowrap;
}
.article-body th {
  background: var(--color-surface-alt);
  font-weight: 600;
  color: var(--color-heading);
}
.article-body tr:nth-child(even) td {
  background: var(--color-surface);
}

/* --- Code --- */
.article-body code {
  background: var(--color-surface-alt);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  font-size: 0.85em;
}
.article-body pre {
  background: var(--color-surface-alt);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 1rem;
  overflow-x: auto;
  margin: 1rem 0 1.5rem;
}
.article-body pre code {
  background: none;
  padding: 0;
}

/* --- Callouts --- */
.callout {
  border-left: 4px solid;
  border-radius: var(--radius-sm);
  padding: 0.75rem 1rem;
  margin: 1rem 0 1.5rem;
}
.callout-label {
  font-weight: 600;
  display: block;
  margin-bottom: 0.25rem;
}
.callout-note {
  border-color: var(--color-info);
  background: var(--color-info-bg);
}
.callout-note .callout-label { color: var(--color-info); }
.callout-warning {
  border-color: var(--color-warning);
  background: var(--color-warning-bg);
}
.callout-warning .callout-label { color: var(--color-warning); }
.callout-tip {
  border-color: var(--color-success);
  background: var(--color-success-bg);
}
.callout-tip .callout-label { color: var(--color-success); }

/* --- Badges --- */
.badge {
  display: inline-block;
  padding: 0.2rem 0.6rem;
  border-radius: 30px;
  font-size: 0.75rem;
  font-weight: 500;
  text-transform: capitalize;
}
.badge-basic { background: var(--color-info-bg); color: var(--color-info); }
.badge-advanced { background: var(--color-purple-bg); color: var(--color-purple); }

/* --- Homepage --- */
.home-hero {
  text-align: center;
  padding: 3rem 1rem 2rem;
}
.home-hero h1 {
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--color-heading);
  margin-bottom: 0.5rem;
}
.home-hero p {
  color: var(--color-muted);
  font-size: 1.1rem;
}
.getting-started-section {
  max-width: 700px;
  margin: 0 auto 2rem;
  padding: 1.5rem 2rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-bg);
}
.getting-started-section h2 {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--color-heading);
  margin-bottom: 1rem;
}
.getting-started-links {
  display: flex;
  gap: 1rem;
  margin-bottom: 1.25rem;
}
.getting-started-link {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 1rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  transition: border-color 0.15s, box-shadow 0.15s;
  color: var(--color-text);
}
.getting-started-link:hover {
  border-color: var(--color-accent);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
  text-decoration: none;
}
.getting-started-link strong { font-size: 1.05rem; }
.getting-started-link span { font-size: 0.85rem; color: var(--color-muted); margin-top: 0.25rem; }
.app-download { margin-bottom: 1rem; }
.app-download p { font-size: 0.95rem; color: var(--color-text); margin-bottom: 0.75rem; }
.app-badges { display: flex; gap: 0.75rem; align-items: center; }
.app-badge { height: 48px; width: auto; border-radius: 6px; }
.getting-started-footer { font-size: 0.9rem; color: var(--color-muted); margin: 0; }

.collection-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.25rem;
  padding: 0 1rem 3rem;
  max-width: 900px;
  margin: 0 auto;
}
.collection-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 2rem 1.5rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  transition: border-color 0.15s, box-shadow 0.15s;
  color: var(--color-text);
}
.collection-card:hover {
  border-color: var(--color-accent);
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
  text-decoration: none;
}
.collection-icon { font-size: 2rem; margin-bottom: 0.75rem; }
.collection-product-img {
  width: 100px;
  height: 100px;
  object-fit: contain;
  margin-bottom: 0.75rem;
  border-radius: var(--radius-sm);
}
.collection-card h2 {
  font-size: 1.2rem;
  color: var(--color-heading);
  margin-bottom: 0.25rem;
}
.collection-card p { font-size: 0.9rem; color: var(--color-muted); margin-bottom: 0.5rem; }
.article-count { font-size: 0.8rem; color: var(--color-muted); }

/* --- Collection page --- */
.collection-header {
  margin-bottom: 1.5rem;
}
.collection-header h1 {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--color-heading);
}
.collection-desc { color: var(--color-muted); margin-top: 0.25rem; }

.category-tabs {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1.25rem;
}
.cat-tab {
  padding: 0.4rem 1rem;
  border: 1px solid var(--color-border);
  border-radius: 30px;
  background: var(--color-bg);
  font-family: var(--font-family);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--color-muted);
  cursor: pointer;
  transition: all 0.15s;
}
.cat-tab:hover { border-color: var(--color-accent); color: var(--color-accent); }
.cat-tab.active {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-accent-contrast);
}

.article-list { display: flex; flex-direction: column; gap: 0.5rem; }
.article-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.25rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  transition: border-color 0.15s, background 0.15s;
  color: var(--color-text);
}
.article-card:hover {
  border-color: var(--color-accent);
  background: var(--color-surface);
  text-decoration: none;
}
.card-content h3 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-heading);
  margin-bottom: 0.15rem;
}
.card-content p {
  font-size: 0.85rem;
  color: var(--color-muted);
  margin: 0;
}

/* --- Footer --- */
.site-footer {
  border-top: 1px solid var(--color-border);
  background: var(--color-bg);
  margin-top: 3rem;
  padding: 1.25rem 1.5rem;
}
.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1.25rem;
  flex-wrap: wrap;
  color: var(--color-muted);
  font-size: 0.85rem;
}
.site-footer a { color: var(--color-muted); text-decoration: none; }
.site-footer a:hover { color: var(--color-accent); }

/* --- Search modal --- */
.search-modal[hidden] { display: none; }
.search-modal {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding-top: 15vh;
}
.search-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.4);
}
.search-dialog {
  position: relative;
  background: var(--color-bg);
  border-radius: var(--radius);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.15);
  width: 90%;
  max-width: 560px;
  max-height: 70vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
.search-input-wrapper {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--color-border);
}
.search-input-wrapper svg { flex-shrink: 0; color: var(--color-muted); }
.search-input-wrapper input {
  flex: 1;
  border: none;
  outline: none;
  font-family: var(--font-family);
  font-size: 1rem;
  color: var(--color-heading);
  background: transparent;
}
.search-input-wrapper kbd {
  padding: 0.15rem 0.4rem;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  font-size: 0.75rem;
  color: var(--color-muted);
  background: var(--color-surface);
}
.search-results {
  overflow-y: auto;
  padding: 0.5rem;
}
.search-result {
  display: block;
  padding: 0.6rem 0.75rem;
  border-radius: var(--radius-sm);
  color: var(--color-text);
  transition: background 0.1s;
}
.search-result:hover, .search-result.focused {
  background: var(--color-surface-alt);
  text-decoration: none;
}
.search-result-title {
  font-weight: 600;
  color: var(--color-heading);
  font-size: 0.9rem;
}
.search-result-meta {
  font-size: 0.8rem;
  color: var(--color-muted);
}
.search-empty {
  padding: 2rem 1rem;
  text-align: center;
  color: var(--color-muted);
  font-size: 0.9rem;
}

/* --- YouTube embeds --- */
.video-embed {
  position: relative;
  padding-bottom: 56.25%;
  height: 0;
  overflow: hidden;
  margin: 0.75rem 0 1rem;
  border-radius: var(--radius-sm);
}
.video-embed iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
  border-radius: var(--radius-sm);
}

/* --- Table of Contents (right rail) --- */
.article-with-toc {
  display: flex;
  gap: 2rem;
}
.article-with-toc .article {
  flex: 1;
  min-width: 0;
}
.toc {
  width: 220px;
  flex-shrink: 0;
  position: sticky;
  top: 100px;
  align-self: flex-start;
  max-height: calc(100vh - 120px);
  overflow-y: auto;
  border-left: 1px solid var(--color-border);
  padding-left: 1rem;
}
.toc h4 {
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-muted);
  margin-bottom: 0.5rem;
}
.toc ul {
  list-style: none;
  margin: 0;
  padding: 0;
}
.toc li {
  margin-bottom: 0.15rem;
}
.toc li a {
  display: block;
  padding: 0.2rem 0;
  font-size: 0.8rem;
  color: var(--color-muted);
  text-decoration: none;
  line-height: 1.35;
  transition: color 0.1s;
}
.toc li a:hover {
  color: var(--color-accent);
  text-decoration: none;
}
.toc .toc-indent {
  padding-left: 0.75rem;
}

/* --- No-underline nav links --- */
.collection-card,
.article-card,
.search-result,
.breadcrumb a {
  text-decoration: none;
}
.article-card:hover,
.collection-card:hover {
  text-decoration: none;
}
/* Footer anchor styles consolidated into the .site-footer block above. */

/* --- Theme toggle --- */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border: none;
  border-radius: 50%;
  background: transparent;
  color: var(--color-muted);
  cursor: pointer;
  transition: background 0.15s;
}
.theme-toggle:hover { background: var(--color-surface-alt); color: var(--color-heading); }
.icon-moon { display: none; }
[data-theme="dark"] .icon-sun { display: none; }
[data-theme="dark"] .icon-moon { display: block; }

/* --- Header right area --- */
.header-right {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.menu-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border: none;
  border-radius: var(--radius-sm);
  background: transparent;
  color: var(--color-text);
  cursor: pointer;
}
.menu-toggle:hover { background: var(--color-surface-alt); }

/* --- Sidebar backdrop (mobile) --- */
.sidebar-backdrop {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.4);
  z-index: 149;
}
.sidebar-backdrop.open { display: block; }

/* --- Responsive --- */
@media (max-width: 768px) {
  .menu-toggle { display: flex; }

  .sidebar {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    width: 280px;
    max-height: 100vh;
    z-index: 150;
    background: var(--color-bg);
    transform: translateX(-100%);
    transition: transform 0.25s ease;
    padding-top: 1.5rem;
    box-shadow: none;
  }
  .sidebar.open {
    transform: translateX(0);
    box-shadow: 4px 0 20px rgba(0, 0, 0, 0.15);
  }

  .toc { display: none; }
  .article-with-toc { flex-direction: column; }
  .main-content { padding: 1rem; }
  .header-inner { padding: 0.5rem 1rem; }
  .search-trigger { min-width: 0; }
  .search-trigger span { display: none; }
  .search-trigger kbd { display: none; }
  .home-hero { padding: 2rem 1rem 1.5rem; }
  .home-hero h1 { font-size: 1.6rem; }
  .getting-started-section { margin: 0 0.5rem 1.5rem; padding: 1rem 1.25rem; }
  .getting-started-links { flex-direction: column; gap: 0.75rem; }
  .collection-grid { grid-template-columns: 1fr 1fr; padding: 0 0.5rem 2rem; gap: 0.75rem; }
  .collection-card { padding: 1.25rem 1rem; }
  .article-header h1 { font-size: 1.5rem; }
  .article-body h2 { font-size: 1.2rem; }
  .article-card { flex-direction: column; align-items: flex-start; gap: 0.5rem; }
  .footer-inner { flex-direction: column; text-align: center; gap: 0.75rem; }

  .search-modal { padding-top: 5vh; }
  .search-dialog { width: 95%; }

  .breadcrumb { font-size: 0.8rem; }
}

@media (max-width: 480px) {
  .collection-grid { grid-template-columns: 1fr; }
  .collection-product-img { width: 70px; height: 70px; }
}