/* ============================================
   云开APPKAIYUN — 全站共享样式
   File: /assets/site.css
   ============================================ */

/* ---------- 1. Reset ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.75;
  color: var(--c-ink);
  background-color: var(--c-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img,
svg,
video {
  display: block;
  max-width: 100%;
  height: auto;
}

ul,
ol {
  list-style: none;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  font: inherit;
  color: inherit;
  background: none;
  border: none;
  cursor: pointer;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  line-height: 1.3;
  font-weight: 900;
  color: var(--c-primary);
}

::selection {
  background: var(--c-accent);
  color: var(--c-primary);
}

::-webkit-scrollbar {
  width: 10px;
}
::-webkit-scrollbar-track {
  background: var(--c-bg);
}
::-webkit-scrollbar-thumb {
  background: var(--c-primary-light);
  border-radius: 5px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--c-primary);
}

/* ---------- 2. CSS Variables ---------- */
:root {
  --c-primary: #0A1F44;
  --c-primary-deep: #06122B;
  --c-primary-light: #1E3A6F;
  --c-accent: #00FF88;
  --c-warm: #FF6A00;
  --c-bg: #F5F7FA;
  --c-ink: #101418;
  --c-muted: #8A94A6;
  --c-subtle: #3D4760;
  --c-green-tint: #E6FFF2;
  --c-orange-tint: #FFF1E8;
  --c-line: #CCD4E0;

  --font-sans: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", "SF Mono", Consolas, "Liberation Mono", monospace;

  --header-h: 72px;
  --container-w: 1200px;
  --gutter: 24px;

  --radius-s: 4px;
  --radius-m: 8px;
  --radius-l: 12px;

  --shadow-s: 0 2px 8px rgba(6, 18, 43, 0.08);
  --shadow-m: 0 6px 24px rgba(6, 18, 43, 0.12);

  --ease: cubic-bezier(0.25, 0.46, 0.45, 0.94);
  --dur: 200ms;
}

/* ---------- 3. Base Typography ---------- */
body {
  font-size: 16px;
  line-height: 1.75;
}

h1 {
  font-size: 36px;
}
h2 {
  font-size: 28px;
}
h3 {
  font-size: 20px;
}

p + p {
  margin-top: 12px;
}

a {
  transition: color var(--dur) var(--ease);
}

:focus-visible {
  outline: 2px solid var(--c-accent);
  outline-offset: 3px;
  border-radius: 2px;
}

/* ---------- 4. Container & Section ---------- */
.container {
  max-width: var(--container-w);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

.section {
  padding: 80px 0;
}

.section-head {
  margin-bottom: 40px;
}

@media (max-width: 600px) {
  .section {
    padding: 48px 0;
  }
}

/* ---------- 5. Skip Link ---------- */
.skip-link {
  position: fixed;
  top: -56px;
  left: 16px;
  z-index: 3000;
  display: inline-block;
  padding: 10px 18px;
  background: var(--c-accent);
  color: var(--c-primary);
  font-weight: 700;
  font-size: 14px;
  border-radius: var(--radius-s);
  transition: top var(--dur) var(--ease);
}
.skip-link:focus {
  top: 16px;
  outline: none;
  box-shadow: 0 0 0 4px rgba(0, 255, 136, 0.35);
}

/* ---------- 6. Header ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-h);
  background: transparent;
  border-bottom: 1px solid transparent;
  transition:
    background-color var(--dur) var(--ease),
    border-color var(--dur) var(--ease),
    box-shadow var(--dur) var(--ease);
}
.site-header[data-scrolled] {
  background: rgba(10, 31, 68, 0.96);
  border-bottom-color: rgba(204, 212, 224, 0.15);
  box-shadow: 0 4px 20px rgba(6, 18, 43, 0.3);
}

.header-inner {
  max-width: var(--container-w);
  height: 100%;
  margin: 0 auto;
  padding: 0 var(--gutter);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

/* ------- Brand ------- */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
  color: #fff;
}
.brand-mark {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  background: var(--c-accent);
  color: var(--c-primary);
  font-size: 17px;
  font-weight: 900;
  border-radius: var(--radius-s);
  flex-shrink: 0;
  box-shadow: 0 2px 10px rgba(0, 255, 136, 0.25);
}
.brand-mark::after {
  content: "";
  position: absolute;
  bottom: -3px;
  right: -3px;
  width: 11px;
  height: 11px;
  background: var(--c-warm);
  border-radius: 2px;
  z-index: -1;
}
.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.25;
}
.brand-name {
  font-size: 18px;
  font-weight: 900;
  letter-spacing: 0.03em;
  color: #fff;
  line-height: 1.25;
}
.brand-tagline {
  font-size: 12px;
  letter-spacing: 0.12em;
  color: rgba(255, 255, 255, 0.55);
}

/* ------- Nav ------- */
.nav-list {
  display: flex;
  align-items: center;
  gap: 6px;
}
.nav-link {
  position: relative;
  display: block;
  padding: 10px 14px;
  font-size: 15px;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.85);
  border-radius: var(--radius-s);
  transition: color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}
.nav-link::after {
  content: "";
  position: absolute;
  bottom: 4px;
  left: 14px;
  right: 14px;
  height: 2px;
  background: var(--c-accent);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--dur) var(--ease);
}
.nav-link:hover {
  color: var(--c-accent);
}
.nav-link:hover::after {
  transform: scaleX(1);
}
.nav-link[aria-current="page"] {
  color: var(--c-accent);
}
.nav-link[aria-current="page"]::after {
  transform: scaleX(1);
  background: var(--c-warm);
}

/* ------- Nav Toggle (Mobile) ------- */
.nav-toggle {
  display: none;
}
.header-progress {
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--c-accent), var(--c-warm));
  z-index: 1;
  pointer-events: none;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--dur) var(--ease), visibility var(--dur);
}
.site-header[data-scrolled] .header-progress {
  opacity: 1;
  visibility: visible;
}

/* ---------- 7. Footer ---------- */
.site-footer {
  position: relative;
  overflow: hidden;
  background: var(--c-primary-deep);
  color: rgba(255, 255, 255, 0.65);
  border-top: 2px solid var(--c-accent);
}
.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    -45deg,
    transparent 0,
    transparent 36px,
    rgba(0, 255, 136, 0.015) 36px,
    rgba(0, 255, 136, 0.015) 37px
  );
  pointer-events: none;
}

.footer-inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.4fr;
  gap: 48px;
  padding-top: 64px;
  padding-bottom: 48px;
}

.footer-brand-name {
  font-size: 22px;
  font-weight: 900;
  letter-spacing: 0.04em;
  color: #fff;
}
.footer-brand-name a {
  color: #fff;
  transition: color var(--dur) var(--ease);
}
.footer-brand-name a:hover {
  color: var(--c-accent);
}
.footer-brand-tagline {
  margin-top: 4px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.1em;
  color: var(--c-accent);
}
.footer-about {
  margin-top: 16px;
  font-size: 14px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.6);
  max-width: 340px;
}
.footer-trust {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid rgba(204, 212, 224, 0.12);
  font-size: 13px;
  color: rgba(255, 255, 255, 0.4);
  max-width: 340px;
}

.footer-heading {
  font-size: 15px;
  font-weight: 700;
  color: #fff;
  letter-spacing: 0.08em;
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid rgba(204, 212, 224, 0.14);
}

.footer-list li {
  font-size: 14px;
  line-height: 2.1;
}
.footer-list a {
  color: rgba(255, 255, 255, 0.6);
  transition: color var(--dur) var(--ease), padding-left var(--dur) var(--ease);
}
.footer-list a:hover {
  color: var(--c-accent);
  padding-left: 4px;
}

.footer-label {
  display: inline-block;
  min-width: 34px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: rgba(255, 255, 255, 0.35);
  letter-spacing: 0.06em;
  margin-right: 6px;
}

.footer-bottom {
  position: relative;
  z-index: 1;
  border-top: 1px solid rgba(204, 212, 224, 0.1);
  background: rgba(0, 0, 0, 0.2);
}
.footer-bottom-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  padding-top: 16px;
  padding-bottom: 16px;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.35);
}

/* ---------- 8. Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 700;
  line-height: 1.4;
  border-radius: var(--radius-s);
  border: 1px solid transparent;
  cursor: pointer;
  transition:
    transform var(--dur) var(--ease),
    box-shadow var(--dur) var(--ease),
    background-color var(--dur) var(--ease),
    border-color var(--dur) var(--ease),
    color var(--dur) var(--ease);
}
.btn-primary {
  background: var(--c-accent);
  color: var(--c-primary);
  box-shadow: 0 2px 12px rgba(0, 255, 136, 0.2);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 255, 136, 0.3);
}
.btn-primary:active {
  transform: translateY(0);
}
.btn-outline {
  background: transparent;
  color: #fff;
  border-color: rgba(255, 255, 255, 0.45);
}
.btn-outline:hover {
  border-color: var(--c-accent);
  color: var(--c-accent);
  box-shadow: inset 0 0 0 1px var(--c-accent);
}

/* ---------- 9. Breadcrumb ---------- */
.breadcrumb {
  font-family: var(--font-mono);
  font-size: 13px;
  color: rgba(255, 255, 255, 0.5);
  margin-bottom: 16px;
}
.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.breadcrumb li {
  display: flex;
  align-items: center;
}
.breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: rgba(255, 255, 255, 0.3);
}
.breadcrumb a {
  color: rgba(255, 255, 255, 0.7);
  transition: color var(--dur) var(--ease);
}
.breadcrumb a:hover {
  color: var(--c-accent);
}
.breadcrumb [aria-current="page"] {
  color: var(--c-accent);
}

.breadcrumb--light {
  color: var(--c-muted);
}
.breadcrumb--light li + li::before {
  color: var(--c-line);
}
.breadcrumb--light a {
  color: var(--c-subtle);
}
.breadcrumb--light a:hover {
  color: var(--c-primary);
}
.breadcrumb--light [aria-current="page"] {
  color: var(--c-primary);
}

/* ---------- 10. Section Index ---------- */
.section-index {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.16em;
  color: var(--c-accent);
  text-transform: uppercase;
}
.section-index::before {
  content: "";
  display: inline-block;
  width: 28px;
  height: 1px;
  background: var(--c-accent);
}
.section-index--dark {
  color: var(--c-primary);
}
.section-index--dark::before {
  background: var(--c-warm);
}

/* ---------- 11. Page Head ---------- */
.page-head {
  position: relative;
  overflow: hidden;
  background: var(--c-primary);
  color: #fff;
  padding: calc(var(--header-h) + 56px) 0 40px;
  border-bottom: 2px solid var(--c-accent);
}
.page-head::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 30%;
  height: 100%;
  background: var(--c-primary-light);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 28% 100%);
  opacity: 0.8;
}
.page-head::after {
  content: "";
  position: absolute;
  top: 0;
  right: 28%;
  width: 2px;
  height: 100%;
  background: var(--c-warm);
  opacity: 0.5;
  transform: rotate(14deg);
  transform-origin: top right;
}
.page-head .container {
  position: relative;
  z-index: 1;
}
.page-head h1 {
  color: #fff;
  font-size: 36px;
  letter-spacing: 0.02em;
}
.page-head-desc {
  margin-top: 8px;
  font-size: 16px;
  color: rgba(255, 255, 255, 0.65);
  max-width: 640px;
}

/* ---------- 12. Hero ---------- */
.hero {
  position: relative;
  overflow: hidden;
  min-height: 82vh;
  display: flex;
  align-items: center;
  background-color: var(--c-primary);
  color: #fff;
}
.hero::before {
  content: "";
  position: absolute;
  top: 0;
  right: -12%;
  width: 55%;
  height: 100%;
  background-color: var(--c-primary-light);
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.045) 1px, transparent 1px);
  background-size: 28px 28px;
  transform: skewX(-14deg);
  border-left: 1px solid rgba(0, 255, 136, 0.2);
  z-index: 0;
}
.hero::after {
  content: "";
  position: absolute;
  top: 0;
  right: 42%;
  width: 3px;
  height: 100%;
  background: linear-gradient(180deg, var(--c-accent), transparent 70%);
  transform: rotate(14deg);
  transform-origin: top right;
  opacity: 0.45;
  z-index: 0;
}
.hero-inner {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 48px;
  width: 100%;
  padding-top: calc(var(--header-h) + 24px);
  padding-bottom: 64px;
}
.hero-content {
  max-width: 620px;
}
.hero-title {
  margin-top: 16px;
  font-size: clamp(36px, 5.5vw, 48px);
  font-weight: 900;
  line-height: 1.12;
  letter-spacing: 0.02em;
  color: #fff;
}
.hero-subtitle {
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 18px;
  letter-spacing: 0.08em;
  color: var(--c-accent);
}
.hero-desc {
  margin-top: 20px;
  font-size: 16px;
  color: rgba(255, 255, 255, 0.7);
  max-width: 560px;
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-top: 32px;
}
.hero-panel {
  width: 280px;
  flex-shrink: 0;
  padding: 28px;
  background: rgba(6, 18, 43, 0.6);
  border: 1px solid rgba(0, 255, 136, 0.25);
  border-radius: var(--radius-m);
  box-shadow: var(--shadow-m);
  font-family: var(--font-mono);
  font-size: 14px;
  color: rgba(255, 255, 255, 0.8);
}
.hero-panel p + p {
  margin-top: 8px;
  border-top: 1px solid rgba(204, 212, 224, 0.1);
  padding-top: 8px;
}
.hero-panel-live {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--c-accent);
  font-size: 13px;
  letter-spacing: 0.12em;
  margin-bottom: 16px;
}
.hero-panel-live::before {
  content: "";
  width: 6px;
  height: 6px;
  background: var(--c-accent);
  border-radius: 50%;
}
.hero-panel-row {
  display: flex;
  justify-content: space-between;
  gap: 16px;
}
.hero-panel-row span:first-child {
  color: rgba(255, 255, 255, 0.45);
}
.hero-panel-row span:last-child {
  color: #fff;
  font-weight: 500;
}

.hero-ticker {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 2;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px var(--gutter);
  background: rgba(6, 18, 43, 0.72);
  border-top: 1px solid rgba(0, 255, 136, 0.25);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.03em;
  color: rgba(255, 255, 255, 0.6);
  backdrop-filter: blur(6px);
}
.hero-ticker::before {
  content: "";
  width: 6px;
  height: 6px;
  background: var(--c-accent);
  border-radius: 50%;
  flex-shrink: 0;
}
.hero-ticker strong {
  color: var(--c-accent);
  font-weight: 500;
}

/* ---------- 13. Cards & Grids ---------- */
.card {
  background: #fff;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-m);
  box-shadow: var(--shadow-s);
  transition: border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease), transform var(--dur) var(--ease);
  overflow: hidden;
}
.card:hover {
  border-color: rgba(0, 255, 136, 0.55);
  box-shadow: var(--shadow-m);
}
.card-body {
  padding: 24px;
}
.card-title {
  font-size: 20px;
  font-weight: 900;
  color: var(--c-primary);
  margin-bottom: 8px;
}
.card-text {
  font-size: 15px;
  color: var(--c-subtle);
  line-height: 1.7;
}
.card-meta {
  margin-top: 16px;
  padding-top: 12px;
  border-top: 1px solid var(--c-line);
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--c-muted);
  letter-spacing: 0.05em;
}

.toc-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.data-panel {
  background: var(--c-primary-deep);
  border: 1px solid rgba(204, 212, 224, 0.15);
  border-radius: var(--radius-m);
  overflow: hidden;
  color: #fff;
}
.data-panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 20px;
  border-bottom: 1px solid rgba(204, 212, 224, 0.1);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  color: var(--c-accent);
}
.data-panel-body {
  padding: 20px;
  font-family: var(--font-mono);
  font-size: 14px;
}

/* ---------- 14. Decorators ---------- */
.mesh-grid {
  position: relative;
  overflow: hidden;
}
.mesh-grid::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
  background-size: 24px 24px;
  pointer-events: none;
}

.img-placeholder {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border-radius: var(--radius-m);
  background: var(--c-primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
}
.img-placeholder::before {
  content: attr(data-label);
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: 0.06em;
  color: rgba(255, 255, 255, 0.45);
  text-align: center;
  padding: 20px;
}
.img-placeholder::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, transparent 0%, transparent 62%, rgba(0, 255, 136, 0.14) 62%, rgba(0, 255, 136, 0.14) 66%, transparent 66%);
  pointer-events: none;
}

/* ---------- 15. Scroll Reveal ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.4s var(--ease), transform 0.4s var(--ease);
}
[data-reveal][data-revealed] {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- 16. Utilities ---------- */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- 17. Responsive ---------- */
@media (max-width: 960px) {
  .footer-inner {
    grid-template-columns: 1fr 1fr;
    gap: 40px;
  }
  .toc-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .hero-panel {
    width: 240px;
  }
}

@media (max-width: 860px) {
  :root {
    --header-h: 60px;
  }

  .nav-toggle {
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 44px;
    height: 44px;
    padding: 10px;
    border-radius: var(--radius-s);
    transition: background-color var(--dur) var(--ease);
  }
  .nav-toggle:hover {
    background: rgba(255, 255, 255, 0.08);
  }
  .nav-toggle-line {
    display: block;
    width: 100%;
    height: 2px;
    background: #fff;
    border-radius: 1px;
    transition: transform var(--dur) var(--ease), opacity var(--dur) var(--ease);
  }
  .nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }
  .nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(2) {
    opacity: 0;
  }
  .nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: rgba(10, 31, 68, 0.97);
    border-bottom: 1px solid rgba(204, 212, 224, 0.12);
    box-shadow: 0 20px 40px rgba(6, 18, 43, 0.3);
    padding: 8px var(--gutter) 16px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease), visibility var(--dur);
  }
  .site-nav[data-open] {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }
  .nav-list {
    flex-direction: column;
    gap: 0;
  }
  .nav-item {
    border-bottom: 1px solid rgba(204, 212, 224, 0.08);
  }
  .nav-item:last-child {
    border-bottom: none;
  }
  .nav-link {
    display: block;
    padding: 14px 4px;
    font-size: 16px;
    border-radius: 0;
  }
  .nav-link::after {
    display: none;
  }
  .nav-link[aria-current="page"] {
    background: rgba(0, 255, 136, 0.08);
  }

  .hero-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 32px;
  }
  .hero-panel {
    display: none;
  }
}

@media (max-width: 600px) {
  :root {
    --gutter: 20px;
  }

  h1 {
    font-size: 30px;
  }
  h2 {
    font-size: 24px;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 36px;
    padding-top: 48px;
    padding-bottom: 36px;
  }
  .toc-grid {
    grid-template-columns: 1fr;
  }
  .footer-bottom-inner {
    flex-direction: column;
    text-align: center;
  }
  .brand-tagline {
    display: none;
  }
  .page-head-desc {
    font-size: 15px;
  }
}

/* ---------- 18. Reduced Motion ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    transition-delay: 0ms !important;
  }
  html {
    scroll-behavior: auto;
  }
  [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }
}