:root {
  --color-surface: #fbfbfb;
  --color-surface-alt: #f2f2f2;
  --color-surface-deep: #e5e6e6;
  --color-ink: #424a4d;
  --color-ink-soft: #646f72;
  --color-ink-muted: #798386;
  --color-line: #dadbdc;
  --color-primary: #377e90;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #e0eaec;
  --color-accent: #1970e6;
  --color-accent-ink: #ffffff;
  --color-highlight: #d2e2f7;
  --color-focus: #0c6cee;
  --color-contrast-surface: #192326;
  --color-contrast-ink: #e4e6e7;
  --color-contrast-line: #464e50;
  --color-contrast-accent: #428aeb;
  --overlay-scrim: linear-gradient(180deg, rgba(25, 35, 38, 0.35) 0%, rgba(25, 35, 38, 0.72) 55%, rgba(25, 35, 38, 0.92) 100%);
  --font-heading: "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --text-xs: 11.4px;
  --text-sm: 14.3px;
  --text-base: 16px;
  --text-lg: 20.0px;
  --text-xl: 25.0px;
  --text-2xl: 31.2px;
  --text-3xl: 39.1px;
  --text-4xl: 48.8px;
  --text-display: clamp(40px, 8.1vw, 104px);
  --text-figure: clamp(33px, 5.9vw, 75px);
  --weight-heading: 695;
  --weight-body: 400;
  --leading-body: 1.85;
  --leading-heading: 1.17;
  --tracking-heading: -0.003em;
  --radius-sm: 7px;
  --radius-md: 7px;
  --radius-lg: 7px;
  --radius-pill: 7px;
  --border-thin: 1px;
  --border-thick: 1px;
  --shadow-1: 0 6px 18px rgba(66, 74, 77, 0.08);
  --shadow-2: 0 18px 44px rgba(66, 74, 77, 0.14);
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1200px;
  --measure: 68ch;
  --gutter: 24px;
  --section-y: 88px;
  --section-y-lg: 123px;
}

/* ============ reset ============ */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
html.nav-open, html.nav-open body { overflow: hidden; }
body {
  margin: 0;
  background-color: 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;
  text-rendering: optimizeLegibility;
}
img, svg, video { max-width: 100%; }
img { display: block; height: auto; }
ul, ol { margin: 0; padding: 0; list-style: none; }
button { font: inherit; cursor: pointer; background: none; border: 0; padding: 0; }
button:disabled { cursor: not-allowed; opacity: 0.5; }
a { color: var(--color-primary); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
:focus-visible { outline: 2px solid var(--color-focus); outline-offset: 2px; border-radius: var(--radius-sm); }
::selection { background-color: var(--color-highlight); color: var(--color-ink); }

/* ============ 中文排版 ============ */
h1, h2, h3, h4, h5, h6 {
  margin: 0 0 var(--space-2);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: color-mix(in srgb, var(--color-ink) 90%, var(--color-primary));
  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, h6 { font-size: var(--text-base); }
p { margin: 0 0 var(--space-2); }
strong { font-weight: var(--weight-heading); }
small { font-size: var(--text-xs); }
.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.01em;
}
.display-title {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-display);
  line-height: 1.04;
  letter-spacing: -0.02em;
  margin: 0;
}
.stat-figure {
  font-family: var(--font-mono);
  font-size: var(--text-figure);
  line-height: 1;
  font-weight: var(--weight-heading);
  letter-spacing: -0.02em;
  color: color-mix(in srgb, var(--color-ink) 74%, var(--color-primary));
}
.eyebrow {
  margin: 0 0 var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}
.lede {
  max-width: var(--measure);
  font-size: var(--text-lg);
  line-height: 1.6;
  color: var(--color-ink-soft);
}
.prose { max-width: var(--measure); }
.prose p + p { margin-top: var(--space-2); }
.prose h2, .prose h3 { margin-top: var(--space-6); }
.index-num {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
  letter-spacing: 0.08em;
}

/* ============ 布局 ============ */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }
.section--alt { background-color: var(--color-surface-alt); }
.section--deep {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}
.section--deep h1, .section--deep h2, .section--deep h3, .section--deep h4 {
  color: var(--color-contrast-ink);
}
.section--deep .eyebrow, .section--deep .lede { color: color-mix(in srgb, var(--color-contrast-ink) 72%, var(--color-contrast-surface)); }
.section--deep a { color: var(--color-contrast-accent); }
.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
}
.auto-grid {
  display: grid;
  gap: var(--space-3);
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}
.stack-3 > * + * { margin-top: var(--space-2); }
.stack-4 > * + * { margin-top: var(--space-4); }
.keyline-list > * + * {
  border-top: var(--border-thin) solid var(--color-line);
  padding-top: var(--space-2);
  margin-top: var(--space-2);
}
.orbit-rule {
  position: relative;
  height: var(--border-thin);
  margin-block: var(--space-6);
  border: 0;
  background-image: linear-gradient(90deg, transparent 0%, var(--color-line) 14%, var(--color-line) 86%, transparent 100%);
}
.orbit-rule::before {
  content: "";
  position: absolute;
  left: 0;
  top: -3px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--color-primary);
}

/* ============ 按钮与标签 ============ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-1);
  padding: 12px 20px;
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  font-weight: 500;
  letter-spacing: 0.02em;
  text-decoration: none;
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}
.btn:hover { text-decoration: none; }
.btn--primary { background-color: var(--color-primary); color: var(--color-primary-ink); }
.btn--primary:hover { background-color: color-mix(in srgb, var(--color-primary) 86%, var(--color-contrast-surface)); color: var(--color-primary-ink); }
.btn--ghost { background-color: var(--color-surface); border-color: var(--color-line); color: var(--color-ink); }
.btn--ghost:hover { border-color: var(--color-primary); color: var(--color-primary); }
.btn--accent { background-color: var(--color-accent); color: var(--color-accent-ink); }
.btn--accent:hover { background-color: color-mix(in srgb, var(--color-accent) 84%, var(--color-contrast-surface)); color: var(--color-accent-ink); }
.btn--pill { border-radius: var(--radius-pill); }
.btn--deep { background-color: var(--color-contrast-surface); color: var(--color-contrast-ink); }
.btn--deep:hover { color: var(--color-contrast-accent); }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  background-color: var(--color-primary-soft);
  color: color-mix(in srgb, var(--color-primary) 78%, var(--color-ink));
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.05em;
}
.tag--invert {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}
.tag--outline {
  background-color: transparent;
  border: var(--border-thin) solid var(--color-line);
  color: var(--color-ink-muted);
}

/* ============ 框体 ============ */
.card, .frame {
  background-color: var(--color-surface);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-1);
  padding: var(--space-3);
}
.card--float { box-shadow: var(--shadow-2); }
.card--dark, .frame--dark {
  background-color: var(--color-contrast-surface);
  border-color: var(--color-contrast-line);
  color: var(--color-contrast-ink);
}
.card--dark a, .frame--dark a { color: var(--color-contrast-accent); }
.frame--inset { background-color: var(--color-surface-deep); box-shadow: none; }

/* ============ 面包屑 ============ */
.breadcrumb {
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
  margin-bottom: var(--space-3);
}
.breadcrumb ol { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-1); }
.breadcrumb li + li::before { content: "/"; margin-right: var(--space-1); color: var(--color-line); }
.breadcrumb a { color: var(--color-ink-soft); }
.breadcrumb a:hover { color: var(--color-primary); }

/* ============ 图片区块（供页面阶段放置图片） ============ */
.media-block {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-1);
  background-color: var(--color-surface-deep);
}
.media-block__img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 0;
}
.media-block__scrim {
  position: absolute;
  inset: 0;
  background-image: var(--overlay-scrim);
  z-index: 1;
}
.media-block__body {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  gap: var(--space-1);
  min-height: 280px;
  padding: var(--space-4);
  color: var(--color-contrast-ink);
}
.media-block__body h2, .media-block__body h3 { color: var(--color-contrast-ink); }
.media-block__body a { color: var(--color-contrast-accent); }
.media-block--ratio-16-9 { aspect-ratio: 16 / 9; }
.media-block--tall .media-block__body { min-height: clamp(320px, 46vw, 520px); }

/* ============ 筛选（仅作用于当前页面已有内容） ============ */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  padding: 6px;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  background-color: var(--color-surface-alt);
}
.filter-btn {
  padding: 8px 14px;
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}
.filter-btn:hover { background-color: var(--color-surface); color: var(--color-ink); }
.filter-btn[aria-pressed="true"] {
  background-color: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-accent-ink);
}
.filter-status {
  margin-left: auto;
  padding-right: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}
[data-filter-item][hidden] { display: none !important; }

/* ============ 滚动显现 ============ */
[data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.45s ease, transform 0.45s ease;
}
[data-reveal].is-visible { opacity: 1; transform: none; }
html:not(.js) [data-reveal] { opacity: 1; transform: none; }

/* ============ 跳转链接 ============ */
.skip-link {
  position: fixed;
  top: var(--space-1);
  left: var(--space-1);
  z-index: 200;
  padding: 10px 16px;
  border-radius: var(--radius-md);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  font-size: var(--text-sm);
  transform: translateY(-180%);
  transition: transform 0.2s ease;
}
.skip-link:focus { transform: none; color: var(--color-contrast-ink); text-decoration: none; }

/* ============ 头部 ============ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  padding-top: var(--space-2);
  pointer-events: none;
}
.header-shell {
  position: relative;
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
  pointer-events: none;
}
.header-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 7px 14px 7px 9px;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  background-color: color-mix(in srgb, var(--color-surface) 92%, transparent);
  box-shadow: var(--shadow-1);
  color: var(--color-ink);
  pointer-events: auto;
}
.brand:hover { color: var(--color-ink); text-decoration: none; border-color: color-mix(in srgb, var(--color-primary) 45%, var(--color-line)); }
.brand-mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: var(--radius-sm);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-accent);
}
.brand-text { display: block; }
.brand-name {
  display: block;
  font-family: var(--font-heading);
  font-size: var(--text-base);
  font-weight: var(--weight-heading);
  line-height: 1.2;
}
.brand-note {
  display: block;
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
  line-height: 1.4;
}
.nav-island {
  padding: 5px;
  border-radius: var(--radius-pill);
  background-color: var(--color-primary);
  box-shadow: var(--shadow-1);
  pointer-events: auto;
}
.nav-list { display: flex; align-items: center; gap: 2px; }
.nav-link {
  display: inline-block;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  color: var(--color-primary-ink);
  font-size: var(--text-sm);
  white-space: nowrap;
  transition: background-color 0.2s ease, color 0.2s ease;
}
.nav-link:hover {
  background-color: color-mix(in srgb, var(--color-primary-ink) 18%, transparent);
  color: var(--color-primary-ink);
  text-decoration: none;
}
.nav-link[aria-current="page"] {
  background-color: var(--color-primary-ink);
  color: var(--color-primary);
}
.nav-link:focus-visible { outline-color: var(--color-primary-ink); }
.header-actions { display: flex; align-items: center; gap: var(--space-1); pointer-events: auto; }
.header-phone {
  padding: 8px 12px;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  background-color: color-mix(in srgb, var(--color-surface) 92%, transparent);
  box-shadow: var(--shadow-1);
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
}
.nav-toggle {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 9px 14px;
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-md);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  font-size: var(--text-sm);
  box-shadow: var(--shadow-1);
  transition: color 0.2s ease, border-color 0.2s ease;
}
.nav-toggle:hover { color: var(--color-contrast-accent); border-color: var(--color-contrast-accent); }
.nav-toggle__bars { display: grid; gap: 5px; width: 16px; }
.nav-toggle__bars span {
  display: block;
  height: 1px;
  background-color: currentColor;
  transition: transform 0.25s ease;
}
.site-header[data-open] .nav-toggle__bars span:first-child { transform: translateY(3px) rotate(45deg); }
.site-header[data-open] .nav-toggle__bars span:last-child { transform: translateY(-3px) rotate(-45deg); }
.header-signature {
  margin: 10px 0 0;
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
  text-align: right;
  letter-spacing: 0.02em;
}
.scroll-trail {
  margin-top: 10px;
  height: 2px;
  border-radius: var(--radius-sm);
  background-color: color-mix(in srgb, var(--color-line) 75%, transparent);
  overflow: hidden;
}
.scroll-trail__fill {
  display: block;
  width: 0;
  height: 100%;
  background-image: linear-gradient(90deg, var(--color-primary) 0%, var(--color-accent) 100%);
}

/* ============ 侧边星图菜单 ============ */
.nav-scrim {
  position: fixed;
  inset: 0;
  z-index: 70;
  background-color: color-mix(in srgb, var(--color-contrast-surface) 58%, transparent);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
  pointer-events: auto;
}
.site-header[data-open] .nav-scrim { opacity: 1; visibility: visible; }
.nav-panel {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  z-index: 80;
  width: min(380px, 88vw);
  height: 100dvh;
  padding: var(--space-4) var(--space-4) var(--space-6);
  overflow-y: auto;
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-right: var(--border-thin) solid var(--color-contrast-line);
  box-shadow: var(--shadow-2);
  transform: translateX(-102%);
  visibility: hidden;
  transition: transform 0.32s cubic-bezier(0.4, 0, 0.2, 1), visibility 0.32s ease;
  pointer-events: auto;
}
.site-header[data-open] .nav-panel { transform: none; visibility: visible; }
.nav-panel__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  padding-bottom: var(--space-2);
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
}
.nav-panel__eyebrow {
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.2em;
  color: var(--color-contrast-accent);
}
.nav-panel__close {
  padding: 6px 12px;
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-sm);
  color: var(--color-contrast-ink);
  font-size: var(--text-sm);
}
.nav-panel__close:hover { border-color: var(--color-contrast-accent); color: var(--color-contrast-accent); }
.nav-map { padding-top: var(--space-3); }
.nav-map__list { position: relative; }
.nav-map__list::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 16px;
  bottom: 16px;
  width: var(--border-thin);
  background-color: var(--color-contrast-line);
}
.nav-map__link {
  position: relative;
  display: flex;
  align-items: baseline;
  gap: var(--space-2);
  padding: 11px 12px 11px 30px;
  border-radius: var(--radius-sm);
  color: var(--color-contrast-ink);
  font-size: var(--text-base);
  transition: background-color 0.2s ease, color 0.2s ease;
}
.nav-map__link::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 50%;
  width: 9px;
  height: 9px;
  margin-top: -5px;
  border-radius: 50%;
  background-color: var(--color-contrast-surface);
  border: var(--border-thin) solid var(--color-contrast-line);
  transition: background-color 0.2s ease, border-color 0.2s ease;
}
.nav-map__link:hover {
  background-color: color-mix(in srgb, var(--color-contrast-accent) 16%, transparent);
  color: var(--color-contrast-ink);
  text-decoration: none;
}
.nav-map__link:hover::before { background-color: var(--color-contrast-accent); border-color: var(--color-contrast-accent); }
.nav-map__link[aria-current="page"] { background-color: var(--color-contrast-accent); color: var(--color-contrast-surface); }
.nav-map__link[aria-current="page"]::before { background-color: var(--color-contrast-surface); border-color: var(--color-contrast-surface); }
.nav-map__link[aria-current="page"] .nav-map__index { color: inherit; }
.nav-map__index { font-size: var(--text-xs); color: var(--color-contrast-accent); letter-spacing: 0.1em; }
.nav-panel__foot {
  margin-top: var(--space-4);
  padding-top: var(--space-3);
  border-top: var(--border-thin) solid var(--color-contrast-line);
  font-size: var(--text-sm);
  color: color-mix(in srgb, var(--color-contrast-ink) 72%, var(--color-contrast-surface));
}
.nav-panel__note { margin: 0; }
.nav-panel__contact { margin: 6px 0 0; color: var(--color-contrast-accent); }

/* ============ 页脚 ============ */
.site-footer {
  margin-top: var(--section-y);
  background-color: var(--color-surface-alt);
  border-top: var(--border-thin) solid var(--color-line);
}
.footer-inner {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding: var(--section-y) var(--gutter) 0;
}
.footer-head { padding-bottom: var(--space-6); }
.footer-eyebrow {
  margin: 0 0 var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.18em;
  color: var(--color-ink-muted);
}
.footer-title {
  margin: 0 0 var(--space-1);
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  color: color-mix(in srgb, var(--color-ink) 90%, var(--color-primary));
}
.footer-lede {
  max-width: var(--measure);
  margin: 0;
  font-size: var(--text-base);
  color: var(--color-ink-soft);
}
.footer-panels {
  display: grid;
  gap: var(--space-3);
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
}
.footer-panel {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  padding: var(--space-3);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  background-color: var(--color-surface);
  box-shadow: var(--shadow-1);
}
.footer-panel__title {
  display: flex;
  align-items: baseline;
  gap: var(--space-1);
  margin: 0;
  padding-bottom: var(--space-1);
  border-bottom: var(--border-thin) solid var(--color-line);
  font-family: var(--font-heading);
  font-size: var(--text-base);
  font-weight: var(--weight-heading);
  color: var(--color-ink);
}
.footer-panel__index { color: var(--color-primary); font-size: var(--text-xs); }
.footer-panel__list {
  display: grid;
  gap: 10px;
  margin: 0;
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
  line-height: 1.65;
}
.footer-panel__note { margin: 0; font-size: var(--text-xs); color: var(--color-ink-muted); }
.footer-panel__list .mono { color: var(--color-ink); font-size: var(--text-sm); }
.footer-link {
  color: var(--color-primary);
  border-bottom: var(--border-thin) solid color-mix(in srgb, var(--color-primary) 35%, transparent);
}
.footer-link:hover { color: var(--color-accent); border-bottom-color: var(--color-accent); text-decoration: none; }
.footer-cta {
  align-self: flex-start;
  margin-top: auto;
  padding: 8px 14px;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  background-color: var(--color-surface-deep);
  font-size: var(--text-sm);
  color: var(--color-ink);
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}
.footer-cta:hover { background-color: var(--color-primary); border-color: var(--color-primary); color: var(--color-primary-ink); text-decoration: none; }
.footer-base {
  margin-top: var(--space-8);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}
.footer-base__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding: var(--space-3) var(--gutter);
}
.footer-base__copy { margin: 0; font-size: var(--text-sm); color: color-mix(in srgb, var(--color-contrast-ink) 82%, var(--color-contrast-surface)); }
.footer-base__meta { margin: 0; font-size: var(--text-xs); color: var(--color-contrast-accent); }

/* ============ 返回顶部 ============ */
.to-top {
  position: fixed;
  right: var(--gutter);
  bottom: var(--gutter);
  z-index: 55;
  padding: 10px 16px;
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-md);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  font-size: var(--text-sm);
  box-shadow: var(--shadow-2);
  transition: color 0.2s ease, border-color 0.2s ease;
}
.to-top:hover { color: var(--color-contrast-accent); border-color: var(--color-contrast-accent); }
[data-to-top][hidden] { display: none !important; }

/* ============ 响应式 ============ */
@media (max-width: 1080px) {
  .nav-link { padding: 8px 11px; }
  .header-phone { display: none; }
}
@media (max-width: 980px) {
  .nav-island { display: none; }
  .header-signature { display: none; }
  .grid-12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }
  .section { padding-block: var(--space-8); }
  .section--lg { padding-block: var(--section-y); }
}
@media (max-width: 640px) {
  .header-bar { gap: var(--space-1); }
  .brand-note { display: none; }
  .nav-toggle__text { display: none; }
  .nav-toggle { padding: 10px; }
  .grid-12 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-base__inner { flex-direction: column; align-items: flex-start; }
  .to-top { right: var(--space-2); bottom: var(--space-2); }
}
@media (max-width: 420px) {
  .brand-name { font-size: var(--text-sm); }
}

/* ============ 减弱动效 ============ */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  [data-reveal] { opacity: 1; transform: none; }
}