/* ==========================================================================
   幻影主站 · 共享样式表 /assets/site.css
  风格：双色海报 —— 相邻分节主色与底色互换，边界靠色差，无阴影无描边
   ========================================================================== */

:root {
  --color-surface: #ffffff;
  --color-surface-alt: #f5f5f5;
  --color-surface-deep: #e8e7e7;
  --color-ink: #3d3337;
  --color-ink-soft: #6e5e65;
  --color-ink-muted: #88777e;
  --color-line: #dcdadb;
  --color-primary: #e3176c;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #fbdfea;
  --color-accent: #0a8084;
  --color-accent-ink: #ffffff;
  --color-highlight: #d3e8e9;
  --color-focus: #038286;
  --color-contrast-surface: #1a0c12;
  --color-contrast-ink: #e7e4e5;
  --color-contrast-line: #473c40;
  --color-contrast-accent: #13e5ec;
  --overlay-scrim: linear-gradient(180deg, rgba(26, 12, 18, 0.35) 0%, rgba(26, 12, 18, 0.72) 55%, rgba(26, 12, 18, 0.92) 100%);
  --font-heading: "Source Han Sans SC", "Noto Sans SC", SimHei, "Microsoft YaHei", sans-serif;
  --font-body: "PingFang SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-mono: ui-monospace, Menlo, Consolas, monospace;
  --text-xs: 11.0px;
  --text-sm: 14.7px;
  --text-base: 17px;
  --text-lg: 22.7px;
  --text-xl: 30.2px;
  --text-2xl: 40.3px;
  --text-3xl: 53.7px;
  --text-4xl: 71.5px;
  --text-display: clamp(51px, 10.4vw, 133px);
  --text-figure: clamp(42px, 7.5vw, 96px);
  --weight-heading: 896;
  --weight-body: 400;
  --leading-body: 1.74;
  --leading-heading: 1.22;
  --tracking-heading: -0.018em;
  --radius-sm: 1px;
  --radius-md: 2px;
  --radius-lg: 2px;
  --radius-pill: 2px;
  --border-thin: 1px;
  --border-thick: 2px;
  --shadow-1: none;
  --shadow-2: none;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1260px;
  --measure: 73ch;
  --gutter: 16px;
  --section-y: 85px;
  --section-y-lg: 119px;
}

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

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

body {
  margin: 0;
  overflow-x: clip;
}

h1, h2, h3, h4, h5, h6,
p, figure, blockquote, dl, dd { margin: 0; }

ul, ol { margin: 0; padding: 0; list-style: none; }

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

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
}

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

table { border-collapse: collapse; width: 100%; }

/* ------------------------------------------------------------- 基础排版 */
body {
  background: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  text-wrap: balance;
}

h1 { font-size: var(--text-3xl); }
h2 { font-size: var(--text-2xl); }
h3 { font-size: var(--text-xl); }
h4 { font-size: var(--text-lg); }
h5 { font-size: var(--text-base); }

p { max-width: var(--measure); }

.mono {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  font-variant-numeric: tabular-nums;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

:focus-visible {
  outline: var(--border-thick) solid var(--color-focus);
  outline-offset: 2px;
}

.skip-link {
  position: fixed;
  top: -120px;
  left: var(--space-2);
  z-index: 200;
  display: inline-block;
  padding: 10px 18px;
  background: var(--color-primary);
  color: var(--color-primary-ink);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
  letter-spacing: 0.08em;
  border-radius: var(--radius-sm);
  transition: top 0.18s ease;
}

.skip-link:focus { top: var(--space-2); }

/* ------------------------------------------------------------ 布局原语 */
.container {
  width: min(100% - var(--space-4), var(--container));
  margin-inline: auto;
}

.band {
  padding-block: var(--section-y);
  background: var(--color-surface);
  color: var(--color-ink);
}

.band--lg { padding-block: var(--section-y-lg); }
.band--alt { background: var(--color-surface-alt); }
.band--deep { background: var(--color-surface-deep); }

.band--primary {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

.band--accent {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}

.band--contrast {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.grid {
  display: grid;
  gap: var(--gutter);
}

.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid--9 { grid-template-columns: repeat(9, minmax(0, 1fr)); }

.stack > * + * { margin-top: var(--space-3); }
.stack--lg > * + * { margin-top: var(--space-6); }

.cluster {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2);
}

.layout-rail {
  display: grid;
  grid-template-columns: minmax(0, 212px) minmax(0, 1fr);
  gap: var(--space-6);
  align-items: start;
}

/* --------------------------------------------------------- 色块与文本色 */
.band--primary .meta-row,
.band--primary .rule-index,
.band--primary .tile__note { color: color-mix(in srgb, var(--color-primary-ink) 72%, transparent); }

.band--accent .meta-row,
.band--accent .rule-index,
.band--accent .tile__note { color: color-mix(in srgb, var(--color-accent-ink) 72%, transparent); }

.band--contrast .meta-row,
.band--contrast .rule-index,
.band--contrast .tile__note { color: color-mix(in srgb, var(--color-contrast-ink) 70%, transparent); }

.index-tag {
  display: inline-block;
  padding: 2px 8px;
  background: var(--color-primary);
  color: var(--color-primary-ink);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  border-radius: var(--radius-sm);
}

.index-tag--accent {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}

.index-tag--muted {
  background: var(--color-surface-deep);
  color: var(--color-ink-soft);
}

.band--contrast .index-tag {
  background: var(--color-contrast-accent);
  color: var(--color-contrast-surface);
}

.meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-ink-muted);
}

/* 编号 + 刻度尺分隔，取代线条 */
.rule-index {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin-block: var(--space-6);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-ink-muted);
}

.rule-index::after {
  content: "";
  flex: 1 1 auto;
  height: 8px;
  background-image: repeating-linear-gradient(90deg, currentColor 0 1px, transparent 1px 12px);
  opacity: 0.5;
}

/* ------------------------------------------------------------ 通用按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 10px 18px;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
  letter-spacing: 0.08em;
  line-height: 1.2;
  border-radius: var(--radius-sm);
  background: var(--color-primary);
  color: var(--color-primary-ink);
  transition: background-color 0.18s ease, color 0.18s ease;
}

.btn:hover { background: var(--color-accent); color: var(--color-accent-ink); }
.btn:focus-visible { background: var(--color-accent); color: var(--color-accent-ink); }

.btn--primary { background: var(--color-primary); color: var(--color-primary-ink); }
.btn--accent { background: var(--color-accent); color: var(--color-accent-ink); }
.btn--accent:hover,
.btn--accent:focus-visible { background: var(--color-primary); color: var(--color-primary-ink); }

.btn--contrast {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.btn--contrast:hover,
.btn--contrast:focus-visible {
  background: var(--color-contrast-accent);
  color: var(--color-contrast-surface);
}

/* ------------------------------------------------------------- 面包屑 */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-ink-muted);
}

.breadcrumb li { display: inline-flex; align-items: center; }

.breadcrumb li::after {
  content: "/";
  margin-left: var(--space-2);
  opacity: 0.45;
}

.breadcrumb li:last-child::after { display: none; }

.band--contrast .breadcrumb,
.band--primary .breadcrumb,
.band--accent .breadcrumb { color: color-mix(in srgb, currentColor 70%, transparent); }

/* ------------------------------------------------------------ 内容单元 */
.tile {
  padding: var(--space-3);
  background: var(--color-surface-alt);
  color: var(--color-ink);
  border-radius: var(--radius-md);
}

.tile--primary { background: var(--color-primary); color: var(--color-primary-ink); }
.tile--accent { background: var(--color-accent); color: var(--color-accent-ink); }
.tile--soft { background: var(--color-primary-soft); }
.tile--highlight { background: var(--color-highlight); }
.tile--deep { background: var(--color-surface-deep); }

.tile--contrast {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.tile__note {
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
  margin-top: var(--space-1);
}

.tile--primary .tile__note,
.tile--accent .tile__note { color: color-mix(in srgb, currentColor 74%, transparent); }

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  background: var(--color-surface-alt);
  color: var(--color-ink);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  border-radius: var(--radius-sm);
  transition: background-color 0.16s ease, color 0.16s ease;
}

.chip:hover { background: var(--color-surface-deep); }

.chip[aria-pressed="true"],
.chip.is-active {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}

.band--contrast .chip {
  background: color-mix(in srgb, var(--color-contrast-ink) 12%, transparent);
  color: var(--color-contrast-ink);
}

/* -------------------------------------------------------------- 数据表 */
.data-table {
  width: 100%;
  font-size: var(--text-sm);
}

.data-table th,
.data-table td {
  padding: var(--space-2);
  text-align: left;
  vertical-align: top;
}

.data-table thead th {
  background: var(--color-surface-deep);
  color: var(--color-ink);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  letter-spacing: 0.06em;
  white-space: nowrap;
}

.data-table tbody tr:nth-child(even) { background: var(--color-surface-alt); }

.data-table tbody td { border-bottom: var(--border-thin) solid var(--color-line); }

.data-table .num {
  font-family: var(--font-mono);
  letter-spacing: 0.08em;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

/* ------------------------------------------------------------ 图片容器 */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  background: var(--color-surface-deep);
  border-radius: calc(var(--radius-md) * 4);
}

.media > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media--16x9 { aspect-ratio: 16 / 9; }
.media--4x3 { aspect-ratio: 4 / 3; }
.media--1x1 { aspect-ratio: 1 / 1; }
.media--tall { aspect-ratio: 3 / 4; }

/* 图上放字必须叠这一层 */
.media__scrim {
  position: absolute;
  inset: 0;
  background: var(--overlay-scrim);
  pointer-events: none;
}

.media__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: var(--space-3);
  color: var(--color-contrast-ink);
  font-size: var(--text-sm);
}

/* ------------------------------------------------------------- 侧栏索引 */
.page-rail {
  position: sticky;
  top: calc(76px + var(--space-4));
  align-self: start;
  counter-reset: rail;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
}

.page-rail ol {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.page-rail li { counter-increment: rail; }

.page-rail a {
  display: flex;
  gap: var(--space-1);
  padding: 6px 8px;
  color: var(--color-ink-muted);
  border-radius: var(--radius-sm);
  transition: background-color 0.16s ease, color 0.16s ease;
}

.page-rail a::before {
  content: counter(rail, decimal-leading-zero);
  color: var(--color-primary);
}

.page-rail a:hover {
  background: var(--color-surface-alt);
  color: var(--color-ink);
}

.page-rail a[aria-current="true"] {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}

.page-rail a[aria-current="true"]::before { color: var(--color-accent-ink); }

/* ---------------------------------------------------------------- 页头 */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background: transparent;
  color: var(--color-contrast-ink);
  transition: background-color 0.28s ease, color 0.28s ease;
}

.site-header.is-solid {
  background: var(--color-surface);
  color: var(--color-ink);
}

.header-bar { position: relative; }

.header-inner {
  width: min(100% - var(--space-4), var(--container));
  margin-inline: auto;
  display: flex;
  align-items: center;
  gap: var(--space-3);
  min-height: 76px;
  padding-block: var(--space-2);
}

.brand {
  display: flex;
  flex-direction: column;
  gap: 2px;
  flex: 0 0 auto;
  min-width: 0;
}

.brand__mark {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  line-height: 1.1;
  letter-spacing: 0.04em;
  white-space: nowrap;
}

.brand__sub {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  opacity: 0.72;
  white-space: nowrap;
}

.site-nav {
  flex: 1 1 auto;
  display: flex;
  justify-content: center;
  min-width: 0;
}

.nav-list {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 2px;
}

.nav-link {
  display: block;
  padding: 7px 11px;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
  letter-spacing: 0.06em;
  line-height: 1.35;
  border-radius: var(--radius-sm);
  transition: background-color 0.16s ease, color 0.16s ease;
}

.nav-link:hover,
.nav-link:focus-visible {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

.nav-link[aria-current="page"] {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

.header-meta {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin-left: auto;
  flex: 0 0 auto;
}

.header-version {
  padding: 4px 8px;
  background: color-mix(in srgb, currentColor 14%, transparent);
  border-radius: var(--radius-sm);
  white-space: nowrap;
}

.header-cta { padding: 9px 16px; }

.nav-toggle {
  display: none;
  position: relative;
  width: 44px;
  height: 44px;
  flex: 0 0 auto;
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-radius: var(--radius-sm);
}

.nav-toggle::before,
.nav-toggle::after {
  content: "";
  position: absolute;
  left: 12px;
  right: 12px;
  height: var(--border-thick);
  background: currentColor;
  transition: transform 0.22s ease;
}

.nav-toggle::before { top: 18px; }
.nav-toggle::after { bottom: 18px; }

.nav-toggle[aria-expanded="true"]::before { transform: translateY(4px) rotate(45deg); }
.nav-toggle[aria-expanded="true"]::after { transform: translateY(-4px) rotate(-45deg); }

.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: var(--border-thick);
  background: var(--color-contrast-accent);
  transform: scaleX(0);
  transform-origin: 0 50%;
  transition: transform 0.1s linear;
}

.version-track {
  display: none;
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.site-header.is-solid .version-track { display: block; }

.version-track__inner {
  width: min(100% - var(--space-4), var(--container));
  margin-inline: auto;
  display: flex;
  flex-wrap: wrap;
  gap: 4px var(--space-4);
  padding-block: 7px;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
}

.version-track__item {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  white-space: nowrap;
}

.version-track__item b {
  font-weight: var(--weight-body);
  color: color-mix(in srgb, var(--color-contrast-ink) 68%, transparent);
}

.version-track__item em {
  font-style: normal;
  color: var(--color-contrast-accent);
}

.version-track__item--tail { margin-left: auto; }

/* ---------------------------------------------------------------- 页脚 */
.site-footer {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  padding-block: var(--section-y) var(--space-4);
  border-radius: 0;
}

.footer-inner {
  width: min(100% - var(--space-4), var(--container));
  margin-inline: auto;
}

.footer-mark {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-2xl);
  line-height: 1.1;
  letter-spacing: 0.04em;
}

.footer-tagline {
  margin-top: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: color-mix(in srgb, var(--color-contrast-ink) 62%, transparent);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: var(--space-6) var(--space-4);
  margin-top: var(--space-8);
}

.footer-title {
  font-size: var(--text-sm);
  letter-spacing: 0.1em;
  margin-bottom: var(--space-2);
  color: var(--color-contrast-ink);
}

.footer-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: var(--text-sm);
}

.footer-list a {
  display: inline-block;
  padding: 2px 0;
  color: color-mix(in srgb, var(--color-contrast-ink) 82%, transparent);
}

.footer-list a:hover,
.footer-list a:focus-visible {
  color: var(--color-contrast-ink);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: var(--border-thick);
  text-decoration-color: var(--color-primary);
}

.footer-list--mono li {
  display: flex;
  justify-content: space-between;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
}

.footer-list--mono em {
  font-style: normal;
  color: var(--color-contrast-accent);
}

.footer-text {
  font-size: var(--text-sm);
  max-width: 34ch;
  color: color-mix(in srgb, var(--color-contrast-ink) 76%, transparent);
}

.footer-text + .footer-text { margin-top: 6px; }

.footer-legal {
  margin-top: var(--space-8);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-4);
  justify-content: space-between;
  align-items: baseline;
  font-size: var(--text-xs);
  color: color-mix(in srgb, var(--color-contrast-ink) 62%, transparent);
}

.footer-legal__note { max-width: 62ch; }

/* ------------------------------------------------------------ 返回顶部 */
.to-top {
  position: fixed;
  right: max(var(--space-2), calc((100vw - var(--container)) / 2 - 84px));
  bottom: var(--space-4);
  z-index: 70;
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 14px;
  background: var(--color-primary);
  color: var(--color-primary-ink);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  border-radius: var(--radius-sm);
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity 0.2s ease, transform 0.2s ease, visibility 0.2s;
}

.to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.to-top:hover,
.to-top:focus-visible {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}

.to-top__tick {
  width: 14px;
  height: 10px;
  background-image: repeating-linear-gradient(90deg, currentColor 0 1px, transparent 1px 3px);
  opacity: 0.85;
}

/* ------------------------------------------------------------- 显现动效 */
.has-js [data-reveal] {
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.34s ease, transform 0.34s ease;
}

.has-js [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ------------------------------------------------------------- 响应式 */
@media (max-width: 1200px) {
  .nav-link { padding: 7px 9px; }
  .header-version { display: none; }
}

@media (max-width: 1040px) {
  .site-header {
    background: var(--color-contrast-surface);
    color: var(--color-contrast-ink);
  }

  .site-header.is-solid {
    background: var(--color-surface);
    color: var(--color-ink);
  }

  .nav-toggle { display: block; }

  .site-nav {
    position: fixed;
    inset: 0;
    z-index: 70;
    flex-direction: column;
    justify-content: center;
    align-items: stretch;
    padding: calc(76px + var(--space-6)) var(--space-4) var(--space-6);
    background: var(--color-contrast-surface);
    color: var(--color-contrast-ink);
    visibility: hidden;
    transform: translateY(-100%);
    transition: transform 0.28s ease, visibility 0.28s;
  }

  .site-nav[data-open] {
    visibility: visible;
    transform: translateY(0);
  }

  .nav-list {
    flex-direction: column;
    justify-content: flex-start;
    gap: 2px;
    width: min(100%, 420px);
    margin-inline: auto;
  }

  .nav-link {
    padding: 14px 16px;
    font-size: var(--text-lg);
    text-align: left;
  }

  .header-meta { margin-left: auto; }

  .version-track__inner { gap: 4px var(--space-2); }

  .layout-rail {
    grid-template-columns: minmax(0, 1fr);
    gap: var(--space-4);
  }

  .page-rail { position: static; }
}

@media (max-width: 760px) {
  .band { padding-block: var(--space-8); }
  .band--lg { padding-block: var(--section-y); }

  .grid--2,
  .grid--3,
  .grid--4,
  .grid--9 { grid-template-columns: minmax(0, 1fr); }

  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }

  .footer-legal { flex-direction: column; align-items: flex-start; }

  .version-track__item--tail { margin-left: 0; }

  .to-top {
    right: var(--space-2);
    bottom: var(--space-2);
  }
}

@media (max-width: 520px) {
  .header-cta { display: none; }

  .brand__mark { font-size: var(--text-base); }
  .brand__sub { font-size: 10px; }

  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .footer-mark { font-size: var(--text-xl); }

  h1 { font-size: var(--text-2xl); }
  h2 { font-size: var(--text-xl); }
  h3 { font-size: var(--text-lg); }
}

/* ------------------------------------------------------- 减弱动效偏好 */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

  .has-js [data-reveal] {
    opacity: 1;
    transform: none;
  }

  .to-top {
    opacity: 1;
    visibility: visible;
    transform: none;
  }
}