/* style.css — Material You Expressive, Celeslyn Adrenalin */

/* =====================================================
   Design
   ===================================================== */
:root {
  --md-primary: #ffffff;
  --md-on-primary: #000000;
  --md-primary-container: #1a1a1a;
  --md-on-primary-container: #f5f5f5;

  --md-secondary: #d1d5db;
  --md-on-secondary: #111111;
  --md-secondary-container: #202020;
  --md-on-secondary-container: #e5e7eb;

  --md-tertiary: #9ca3af;
  --md-on-tertiary: #000000;
  --md-tertiary-container: #262626;
  --md-on-tertiary-container: #f3f4f6;

  --md-error: #ef4444;
  --md-on-error: #ffffff;
  --md-error-container: #7f1d1d;
  --md-on-error-container: #fecaca;

  --md-surface: #000000;
  --md-on-surface: #ffffff;

  --md-surface-variant: #1f1f1f;
  --md-on-surface-variant: #cfcfcf;

  --md-surface-dim: #050505;
  --md-surface-bright: #161616;

  --md-surface-container-lowest: #000000;
  --md-surface-container-low: #0d0d0d;
  --md-surface-container: #121212;
  --md-surface-container-high: #1a1a1a;
  --md-surface-container-highest: #242424;

  --md-inverse-surface: #ffffff;
  --md-inverse-on-surface: #000000;
  --md-inverse-primary: #111111;

  --md-outline: #525252;
  --md-outline-variant: #2a2a2a;

  --md-scrim: rgba(0, 0, 0, 0.7);

  /* Shape — expressive scale */
  --md-shape-xs: 4px;
  --md-shape-sm: 8px;
  --md-shape-md: 12px;
  --md-shape-lg: 16px;
  --md-shape-xl: 28px;
  --md-shape-2xl: 36px;
  --md-shape-full: 999px;

  /* Motion */
  --md-easing-emphasized: cubic-bezier(0.2, 0, 0, 1);
  --md-easing-emphasized-decelerate: cubic-bezier(0.05, 0.7, 0.1, 1);
  --md-easing-standard: cubic-bezier(0.4, 0, 0.2, 1);
  --md-duration-short1: 100ms;
  --md-duration-short2: 150ms;
  --md-duration-short3: 200ms;
  --md-duration-short4: 250ms;
  --md-duration-medium2: 350ms;
  --md-duration-long2: 500ms;
  --md-duration-extra-long: 700ms;

  /* Type families */
  --font-display: 'Montserrat', system-ui, sans-serif;
  --font-body: 'TikTok Sans', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  /* Layout */
  --app-bar-height: 64px;
  --nav-rail-width: 248px;
  --max-content-width: 1200px;
}

/* =====================================================
   Reset
   ===================================================== */
*, *::before, *::after 
{ box-sizing: border-box; margin: 0; padding: 0; -webkit-tap-highlight-color: transparent; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; }}

body {
  background: var(--md-surface);
  color: var(--md-on-surface);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  min-height: 100vh;
  overflow-x: hidden;
}

img { display: block; max-width: 100%; height: auto; }
button { background: none; border: none; color: inherit; font: inherit; cursor: pointer; }
a { color: inherit; text-decoration: none; }
input { font: inherit; color: inherit; }

.material-symbols-outlined {
  font-family: 'Material Symbols Outlined';
  font-weight: normal;
  font-style: normal;
  font-size: 24px;
  line-height: 1;
  letter-spacing: normal;
  text-transform: none;
  display: inline-block;
  white-space: nowrap;
  word-wrap: normal;
  direction: ltr;
  font-variation-settings: 'FILL' 0, 'wght' 400, 'GRAD' 0, 'opsz' 24;
}

/* =====================================================
   App bar
   ===================================================== */
.app-bar {
  position: sticky;
  top: 0;
  z-index: 50;
  height: var(--app-bar-height);
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 0 16px;
  background: color-mix(in srgb, var(--md-surface) 85%, transparent);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid var(--md-outline-variant);
}

.menu-toggle { display: none; }

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1rem;
  letter-spacing: -0.01em;
  flex-shrink: 0;
}
.brand-mark {
  display: grid;
  place-items: center;
  width: 32px; height: 32px;
  border-radius: var(--md-shape-sm);
  background: var(--md-primary);
  color: var(--md-on-primary);
  font-weight: 900;
  font-size: 14px;
}
.brand-suffix {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--md-on-surface-variant);
  padding: 2px 6px;
  border: 1px solid var(--md-outline-variant);
  border-radius: var(--md-shape-xs);
  margin-left: 2px;
}

.search-bar {
  position: relative;
  flex: 1;
  max-width: 560px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  height: 44px;
  padding: 0 8px 0 16px;
  background: var(--md-surface-container-high);
  border-radius: var(--md-shape-full);
  border: 1px solid transparent;
  transition: border-color var(--md-duration-short3) var(--md-easing-standard),
              background var(--md-duration-short3) var(--md-easing-standard);
}
.search-bar:focus-within {
  background: var(--md-surface-container-highest);
  border-color: var(--md-primary);
}
.search-leading {
  font-size: 20px;
  color: var(--md-on-surface-variant);
  margin-right: 12px;
}
.search-bar input {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  font-size: 0.95rem;
  color: var(--md-on-surface);
  min-width: 0;
}
.search-bar input::placeholder { color: var(--md-on-surface-variant); }
.search-kbd {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 3px 8px;
  background: var(--md-surface-container-highest);
  border: 1px solid var(--md-outline-variant);
  border-radius: var(--md-shape-xs);
  color: var(--md-on-surface-variant);
  flex-shrink: 0;
}

.icon-button {
  display: grid;
  place-items: center;
  width: 44px; height: 44px;
  border-radius: var(--md-shape-full);
  color: var(--md-on-surface);
  transition: background var(--md-duration-short3) var(--md-easing-standard);
}
.icon-button:hover { background: color-mix(in srgb, var(--md-on-surface) 8%, transparent); }

/* =====================================================
   Scroll progress
   ===================================================== */
.scroll-progress {
  position: sticky;
  top: var(--app-bar-height);
  z-index: 49;
  height: 2px;
  background: transparent;
  transform-origin: left;
  transform: scaleX(0);
  transition: transform 80ms linear;
}
.scroll-progress::after {
  content: '';
  display: block;
  width: 100%; height: 100%;
  background: var(--md-primary);
}

/* =====================================================
   Layout
   ===================================================== */
.layout {
  display: grid;
  grid-template-columns: var(--nav-rail-width) 1fr;
  min-height: calc(100vh - var(--app-bar-height));
}

.main {
  outline: none;
  padding: 32px 40px 80px;
  min-width: 0;
}

/* =====================================================
   Navigation rail
   ===================================================== */
.nav-rail {
  position: sticky;
  top: var(--app-bar-height);
  align-self: start;
  height: calc(100vh - var(--app-bar-height));
  padding: 24px 16px;
  border-right: 1px solid var(--md-outline-variant);
  overflow-y: auto;
}
.nav-rail-inner { display: flex; flex-direction: column; gap: 4px; }
.nav-rail-divider {
  height: 1px;
  background: var(--md-outline-variant);
  margin: 16px 12px;
}
.nav-rail-section-label {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--md-on-surface-variant);
  padding: 8px 16px 12px;
}
.nav-rail-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 0 16px;
  height: 48px;
  border-radius: var(--md-shape-lg);
  color: var(--md-on-surface-variant);
  font-weight: 500;
  font-size: 0.92rem;
  transition: background var(--md-duration-short3) var(--md-easing-standard),
              color var(--md-duration-short3) var(--md-easing-standard);
}
.nav-rail-item .material-symbols-outlined { font-size: 22px; flex-shrink: 0; }
.nav-rail-item:hover {
  background: color-mix(in srgb, var(--md-on-surface) 6%, transparent);
  color: var(--md-on-surface);
}
.nav-rail-item.is-active {
  background: var(--md-secondary-container);
  color: var(--md-on-secondary-container);
  font-weight: 600;
}
.nav-rail-item.is-active .material-symbols-outlined {
  font-variation-settings: 'FILL' 1, 'wght' 500, 'GRAD' 0, 'opsz' 24;
}

/* =====================================================
   Generic motion utilities
   ===================================================== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity var(--md-duration-long2) var(--md-easing-emphasized-decelerate),
              transform var(--md-duration-long2) var(--md-easing-emphasized-decelerate);
}
.reveal.is-in { opacity: 1; transform: none; }

.stagger > * {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--md-duration-long2) var(--md-easing-emphasized-decelerate),
              transform var(--md-duration-long2) var(--md-easing-emphasized-decelerate);
}
.stagger.is-in > * { opacity: 1; transform: none; }
.stagger.is-in > *:nth-child(1) { transition-delay: 0ms; }
.stagger.is-in > *:nth-child(2) { transition-delay: 60ms; }
.stagger.is-in > *:nth-child(3) { transition-delay: 120ms; }
.stagger.is-in > *:nth-child(4) { transition-delay: 180ms; }
.stagger.is-in > *:nth-child(5) { transition-delay: 240ms; }
.stagger.is-in > *:nth-child(6) { transition-delay: 300ms; }
.stagger.is-in > *:nth-child(7) { transition-delay: 360ms; }
.stagger.is-in > *:nth-child(8) { transition-delay: 420ms; }

/* Line mask rise — for article headlines */
.line-rise { display: block; overflow: hidden; }
.line-rise > .inner {
  display: block;
  transform: translateY(110%);
  transition: transform var(--md-duration-extra-long) var(--md-easing-emphasized-decelerate);
  transition-delay: calc(var(--i, 0) * 140ms);
}
.line-rise.is-in > .inner { transform: translateY(0); }

/* =====================================================
   Eyebrow with rule
   ===================================================== */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--md-primary);
  margin-bottom: 24px;
}
.eyebrow::after {
  content: '';
  display: inline-block;
  width: 0;
  height: 1px;
  background: currentColor;
  transition: width 800ms var(--md-easing-standard) 300ms;
}
.eyebrow.is-in::after { width: 2.5rem; }

/* =====================================================
   Home view
   ===================================================== */
.home-hero {
  max-width: var(--max-content-width);
  margin: 0 auto 56px;
  padding: 24px 0 48px;
}
.home-hero h1 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.75rem, 5.5vw, 4.5rem);
  line-height: 0.95;
  letter-spacing: -0.025em;
  margin-bottom: 28px;
  max-width: 16ch;
}
.home-hero .lead {
  font-size: 1.125rem;
  line-height: 1.55;
  color: var(--md-on-surface-variant);
  max-width: 58ch;
  margin-bottom: 36px;
}
.home-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--md-outline-variant);
}
.home-stat .num {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 2.5rem;
  letter-spacing: -0.02em;
  color: var(--md-primary);
  line-height: 1;
  display: block;
}
.home-stat .label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--md-on-surface-variant);
  margin-top: 8px;
  display: block;
}

.section-head {
  max-width: var(--max-content-width);
  margin: 0 auto 28px;
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
}
.section-head h2 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.5rem, 2.5vw, 2rem);
  letter-spacing: -0.015em;
  line-height: 1.1;
}
.section-head a {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--md-primary);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  flex-shrink: 0;
}
.section-head a .material-symbols-outlined { font-size: 16px; }

/* Featured article */
.featured-card {
  max-width: var(--max-content-width);
  margin: 0 auto 64px;
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  background: var(--md-surface-container);
  border-radius: var(--md-shape-2xl);
  overflow: hidden;
  border: 1px solid var(--md-outline-variant);
}
.featured-card__media {
  position: relative;
  aspect-ratio: 4 / 3;
  overflow: hidden;
  background: var(--md-surface-container-high);
}
.featured-card__media img {
  width: 100%; height: 100%;
  object-fit: cover;
  transition: transform var(--md-duration-extra-long) var(--md-easing-emphasized);
}
.featured-card:hover .featured-card__media img { transform: scale(1.04); }
.featured-card__body {
  padding: 40px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 20px;
}
.featured-card__title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.625rem, 2.5vw, 2.25rem);
  line-height: 1.05;
  letter-spacing: -0.02em;
}
.featured-card__excerpt {
  color: var(--md-on-surface-variant);
  line-height: 1.55;
  font-size: 1rem;
}

/* Buttons */
.btn-filled, .btn-tonal, .btn-text {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 44px;
  padding: 0 24px;
  border-radius: var(--md-shape-full);
  font-weight: 600;
  font-size: 0.9rem;
  letter-spacing: 0.01em;
  transition: background var(--md-duration-short3) var(--md-easing-standard),
              transform var(--md-duration-short2) var(--md-easing-standard);
  align-self: flex-start;
}
.btn-filled {
  background: var(--md-primary);
  color: var(--md-on-primary);
}
.btn-filled:hover { background: color-mix(in srgb, var(--md-primary) 88%, white); }
.btn-tonal {
  background: var(--md-secondary-container);
  color: var(--md-on-secondary-container);
}
.btn-tonal:hover { background: color-mix(in srgb, var(--md-secondary-container) 88%, white); }
.btn-text {
  padding: 0 12px;
  color: var(--md-primary);
}
.btn-text:hover { background: color-mix(in srgb, var(--md-primary) 8%, transparent); }
.btn-filled .material-symbols-outlined,
.btn-tonal .material-symbols-outlined,
.btn-text .material-symbols-outlined { font-size: 18px; }

/* Meta row */
.meta-row {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--md-on-surface-variant);
}
.meta-row .dot {
  width: 3px; height: 3px;
  border-radius: 50%;
  background: var(--md-on-surface-variant);
}

/* Category grid */
.category-grid {
  max-width: var(--max-content-width);
  margin: 0 auto 64px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}
.category-card {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 24px;
  background: var(--md-surface-container);
  border: 1px solid var(--md-outline-variant);
  border-radius: var(--md-shape-xl);
  min-height: 180px;
  transition: background var(--md-duration-short3) var(--md-easing-standard),
              transform var(--md-duration-short3) var(--md-easing-standard),
              border-color var(--md-duration-short3) var(--md-easing-standard);
}
.category-card:hover {
  background: var(--md-surface-container-high);
  border-color: var(--md-primary);
  transform: translateY(-2px);
}
.category-card__icon {
  display: grid;
  place-items: center;
  width: 48px; height: 48px;
  border-radius: var(--md-shape-md);
  background: var(--md-primary-container);
  color: var(--md-on-primary-container);
}
.category-card__icon .material-symbols-outlined { font-size: 24px; }
.category-card__name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.125rem;
  letter-spacing: -0.01em;
  margin-top: auto;
}
.category-card__tagline {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--md-on-surface-variant);
}

/* Article list */
.article-list {
  max-width: var(--max-content-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
}
.article-card {
  display: flex;
  flex-direction: column;
  background: var(--md-surface-container);
  border: 1px solid var(--md-outline-variant);
  border-radius: var(--md-shape-xl);
  overflow: hidden;
  transition: background var(--md-duration-short3) var(--md-easing-standard),
              transform var(--md-duration-short3) var(--md-easing-standard),
              border-color var(--md-duration-short3) var(--md-easing-standard);
}
.article-card:hover {
  background: var(--md-surface-container-high);
  border-color: var(--md-primary);
  transform: translateY(-2px);
}
.article-card__media {
  aspect-ratio: 16 / 10;
  overflow: hidden;
  background: var(--md-surface-container-high);
}
.article-card__media img {
  width: 100%; height: 100%;
  object-fit: cover;
  transition: transform var(--md-duration-extra-long) var(--md-easing-emphasized);
}
.article-card:hover .article-card__media img { transform: scale(1.05); }
.article-card__body {
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  flex: 1;
}
.article-card__category {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--md-primary);
}
.article-card__title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.125rem;
  line-height: 1.2;
  letter-spacing: -0.01em;
}
.article-card__excerpt {
  font-size: 0.875rem;
  line-height: 1.55;
  color: var(--md-on-surface-variant);
  flex: 1;
}
.article-card__meta {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--md-on-surface-variant);
  padding-top: 12px;
  border-top: 1px solid var(--md-outline-variant);
}

/* =====================================================
   Category view
   ===================================================== */
.category-hero {
  max-width: var(--max-content-width);
  margin: 0 auto 48px;
  padding: 24px 0;
}
.category-hero h1 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.25rem, 4.5vw, 3.5rem);
  letter-spacing: -0.025em;
  line-height: 0.95;
  margin-bottom: 20px;
  max-width: 18ch;
}
.category-hero .lead {
  font-size: 1.05rem;
  color: var(--md-on-surface-variant);
  max-width: 56ch;
  line-height: 1.55;
}

/* =====================================================
   Article view
   ===================================================== */
.article-view { max-width: 760px; margin: 0 auto; }
.article-header {
  padding: 24px 0 40px;
  border-bottom: 1px solid var(--md-outline-variant);
  margin-bottom: 40px;
}
.article-header .back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--md-on-surface-variant);
  margin-bottom: 28px;
  transition: color var(--md-duration-short3) var(--md-easing-standard);
}
.article-header .back-link:hover { color: var(--md-primary); }
.article-header .back-link .material-symbols-outlined { font-size: 16px; }

.article-title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.25rem, 5vw, 3.5rem);
  line-height: 0.98;
  letter-spacing: -0.025em;
  margin: 20px 0 24px;
}
.article-excerpt {
  font-size: 1.125rem;
  line-height: 1.55;
  color: var(--md-on-surface-variant);
  max-width: 56ch;
  margin-bottom: 32px;
}

.article-cover {
  margin: 0 0 40px;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border-radius: var(--md-shape-2xl);
  background: var(--md-surface-container);
}
.article-cover img { width: 100%; height: 100%; object-fit: cover; }

.article-section {
  margin-bottom: 56px;
  scroll-margin-top: calc(var(--app-bar-height) + 24px);
}
.article-section h2 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.5rem, 2.5vw, 1.875rem);
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 20px;
  display: flex;
  align-items: baseline;
  gap: 14px;
}
.article-section h2::before {
  content: '';
  display: inline-block;
  width: 24px; height: 2px;
  background: var(--md-primary);
  flex-shrink: 0;
  transform: translateY(-6px);
}
.article-section p {
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}
.article-section p:last-child { margin-bottom: 0; }

/* Pull quote / callout */
.callout {
  background: var(--md-surface-container);
  border-left: 3px solid var(--md-primary);
  padding: 24px 28px;
  border-radius: 0 var(--md-shape-lg) var(--md-shape-lg) 0;
  margin: 32px 0;
}
.callout p {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.25rem;
  line-height: 1.35;
  color: var(--md-on-surface);
  margin: 0;
}

/* Tags */
.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 40px;
  padding-top: 24px;
  border-top: 1px solid var(--md-outline-variant);
}
.tag {
  display: inline-flex;
  align-items: center;
  height: 32px;
  padding: 0 12px;
  border-radius: var(--md-shape-full);
  background: var(--md-surface-container-high);
  border: 1px solid var(--md-outline-variant);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--md-on-surface-variant);
}
.tag::before {
  content: '#';
  margin-right: 4px;
  color: var(--md-primary);
}

/* Related */
.related {
  margin-top: 80px;
  padding-top: 48px;
  border-top: 1px solid var(--md-outline-variant);
}
.related h3 {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--md-on-surface-variant);
  margin-bottom: 24px;
}
.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 16px;
}

/* =====================================================
   Table of contents
   ===================================================== */
.toc {
  position: sticky;
  top: calc(var(--app-bar-height) + 32px);
  align-self: start;
  max-height: calc(100vh - var(--app-bar-height) - 64px);
  overflow-y: auto;
  padding: 24px;
}
.toc-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--md-on-surface-variant);
  margin-bottom: 16px;
}
.toc-nav { display: flex; flex-direction: column; gap: 2px; }
.toc-link {
  display: block;
  padding: 8px 12px;
  border-radius: var(--md-shape-sm);
  font-size: 0.85rem;
  line-height: 1.4;
  color: var(--md-on-surface-variant);
  border-left: 2px solid transparent;
  transition: background var(--md-duration-short3) var(--md-easing-standard),
              color var(--md-duration-short3) var(--md-easing-standard),
              border-color var(--md-duration-short3) var(--md-easing-standard);
}
.toc-link:hover {
  color: var(--md-on-surface);
  background: color-mix(in srgb, var(--md-on-surface) 5%, transparent);
}
.toc-link.is-active {
  color: var(--md-primary);
  border-left-color: var(--md-primary);
  background: color-mix(in srgb, var(--md-primary) 8%, transparent);
  font-weight: 500;
}

/* =====================================================
   Search dropdown
   ===================================================== */
.search-dropdown {
  position: fixed;
  top: calc(var(--app-bar-height) + 8px);
  left: 50%;
  transform: translateX(-50%);
  width: calc(100% - 32px);
  max-width: 560px;
  max-height: 60vh;
  overflow-y: auto;
  background: var(--md-surface-container-high);
  border: 1px solid var(--md-outline-variant);
  border-radius: var(--md-shape-lg);
  padding: 8px;
  z-index: 60;
  box-shadow: var(--md-elevation-3, 0 4px 16px rgba(0,0,0,0.4));
}
.search-result {
  display: block;
  padding: 12px 16px;
  border-radius: var(--md-shape-md);
  transition: background var(--md-duration-short3) var(--md-easing-standard);
}
.search-result:hover, .search-result.is-active {
  background: color-mix(in srgb, var(--md-on-surface) 6%, transparent);
}
.search-result__category {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--md-primary);
  margin-bottom: 4px;
}
.search-result__title {
  font-weight: 600;
  font-size: 0.95rem;
  margin-bottom: 2px;
}
.search-result__excerpt {
  font-size: 0.8rem;
  color: var(--md-on-surface-variant);
  line-height: 1.4;
  overflow: hidden;
  display: -webkit-box;
  -webkit-line-clamp: 1;
  -webkit-box-orient: vertical;
}
.search-empty {
  padding: 32px 16px;
  text-align: center;
  color: var(--md-on-surface-variant);
  font-size: 0.9rem;
}

/* =====================================================
   FAB
   ===================================================== */
.fab {
  position: fixed;
  right: 24px;
  bottom: 24px;
  display: grid;
  place-items: center;
  width: 56px; height: 56px;
  border-radius: var(--md-shape-lg);
  background: var(--md-primary);
  color: var(--md-on-primary);
  box-shadow: 0 4px 16px rgba(0,0,0,0.4);
  z-index: 40;
  transition: transform var(--md-duration-short3) var(--md-easing-emphasized),
              opacity var(--md-duration-short3) var(--md-easing-standard);
}
.fab:hover { transform: scale(1.05); }
.fab[hidden] {
  opacity: 0;
  pointer-events: none;
  transform: scale(0.8);
}

/* =====================================================
   Bottom navigation (mobile)
   ===================================================== */
.bottom-nav {
  display: none;
  position: fixed;
  bottom: 0; left: 0; right: 0;
  height: 72px;
  background: color-mix(in srgb, var(--md-surface) 92%, transparent);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-top: 1px solid var(--md-outline-variant);
  padding: 8px 0 12px;
  z-index: 40;
}
.bottom-nav-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
  color: var(--md-on-surface-variant);
  font-size: 0.7rem;
  font-weight: 500;
  transition: color var(--md-duration-short3) var(--md-easing-standard);
}
.bottom-nav-item .material-symbols-outlined { font-size: 24px; }
.bottom-nav-item.is-active { color: var(--md-primary); }
.bottom-nav-item.is-active .material-symbols-outlined {
  font-variation-settings: 'FILL' 1, 'wght' 500;
}

/* Scrim */
.scrim {
  position: fixed;
  inset: 0;
  background: var(--md-scrim);
  z-index: 55;
  opacity: 0;
  transition: opacity var(--md-duration-medium2) var(--md-easing-standard);
}
.scrim.is-visible { opacity: 1; }

/* Sheet */
.sheet {
  position: fixed;
  left: 8px; right: 8px;
  bottom: 80px;
  background: var(--md-surface-container-high);
  border: 1px solid var(--md-outline-variant);
  border-radius: var(--md-shape-xl);
  padding: 16px;
  z-index: 56;
  transform: translateY(120%);
  transition: transform var(--md-duration-medium2) var(--md-easing-emphasized);
}
.sheet.is-open { transform: translateY(0); }
.sheet-handle {
  width: 32px; height: 4px;
  background: var(--md-outline);
  border-radius: 2px;
  margin: 0 auto 16px;
}
.sheet-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--md-on-surface-variant);
  margin-bottom: 12px;
  padding: 0 8px;
}
.sheet-nav { display: flex; flex-direction: column; gap: 2px; }
.sheet-nav a {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 16px;
  border-radius: var(--md-shape-lg);
  color: var(--md-on-surface);
  font-weight: 500;
}
.sheet-nav a:hover { background: var(--md-surface-container-highest); }
.sheet-nav a .material-symbols-outlined { font-size: 22px; }

/* =====================================================
   About / 404
   ===================================================== */
.static-page {
  max-width: 720px;
  margin: 0 auto;
  padding: 24px 0;
}
.static-page h1 {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2rem, 4vw, 3rem);
  letter-spacing: -0.02em;
  line-height: 1;
  margin-bottom: 28px;
}
.static-page p {
  font-size: 1.0625rem;
  line-height: 1.7;
  color: var(--md-on-surface);
  margin-bottom: 1.2em;
}

/* =====================================================
   Responsive — tablet
   ===================================================== */
@media (max-width: 1100px) {
  :root { --nav-rail-width: 80px; }
  .nav-rail-item .nav-rail-label { display: none; }
  .nav-rail-item { justify-content: center; padding: 0; }
  .nav-rail-section-label { display: none; }
  .featured-card { grid-template-columns: 1fr; }
  .featured-card__media { aspect-ratio: 16 / 9; }
  .toc { display: none; }
}

/* =====================================================
   Responsive — mobile
   ===================================================== */
@media (max-width: 768px) {
  :root { --app-bar-height: 56px; }
  .app-bar { padding: 0 12px; gap: 8px; }
  .menu-toggle { display: grid; }
  .brand-name { display: none; }
  .brand-suffix { display: none; }
  .brand { gap: 0; }
  .search-bar { height: 40px; padding-left: 12px; }
  .search-kbd { display: none; }
  .icon-button[aria-label="Bookmarks"] { display: none; }

  .layout { grid-template-columns: 1fr; }

  .nav-rail {
    position: fixed;
    top: var(--app-bar-height);
    left: 0; bottom: 0;
    width: 280px;
    height: calc(100vh - var(--app-bar-height));
    background: var(--md-surface-container-low);
    transform: translateX(-100%);
    transition: transform var(--md-duration-medium2) var(--md-easing-emphasized);
    z-index: 56;
    padding: 16px;
  }
  .nav-rail.is-open { transform: translateX(0); }
  .nav-rail-item .nav-rail-label { display: inline; }
  .nav-rail-item { justify-content: flex-start; padding: 0 16px; }
  .nav-rail-section-label { display: block; }

  .main { padding: 20px 16px 96px; }

  .bottom-nav { display: flex; }
  .fab { bottom: 88px; right: 16px; }

  .featured-card__body { padding: 24px; }
  .featured-card { border-radius: var(--md-shape-xl); }

  .home-stats { gap: 24px 32px; }
  .home-stat .num { font-size: 1.75rem; }

  .section-head { flex-direction: column; align-items: flex-start; gap: 8px; }

  .article-header { padding: 12px 0 28px; margin-bottom: 28px; }
  .article-section { margin-bottom: 40px; }
  .article-section p { font-size: 1rem; }
  
  .article-section a,
  .static-page a {
    color: var(--md-primary);
    text-decoration: underline;
    text-decoration-thickness: 2px;
    text-underline-offset: 3px;
  }

  .callout { padding: 20px; }
  .callout p { font-size: 1.0625rem; }
}

@media (max-width: 480px) {
  .article-cover { border-radius: var(--md-shape-xl); }
  .category-grid { grid-template-columns: 1fr; }
}

/* =====================================================
   Reduced motion
   ===================================================== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    transition-duration: 0.001ms !important;
  }
  .reveal, .stagger > *, .line-rise > .inner {
    opacity: 1 !important;
    transform: none !important;
  }
}

/* =====================================================
   Pointer coarse fallbacks
   ===================================================== */
@media (pointer: coarse) {
  .article-card:hover,
  .category-card:hover,
  .featured-card:hover .featured-card__media img,
  .article-card:hover .article-card__media img {
    transform: none;
  }
}

/* Desktop */
@media (min-width: 769px) {
  .menu-toggle {
    display: none !important;
  }
  .article-section a,
  .static-page a {
    color: var(--md-primary);
    text-decoration: underline;
    text-decoration-thickness: 2px;
    text-underline-offset: 3px;
  }
}

.policy-item {
  padding: 12px 16px;
  margin: 12px 0;
  background: var(--md-surface-container);
  border-radius: 12px;
}

body.menu-open {
  overflow: hidden;
  touch-action: none;
}