:root {
  --color-surface: #edecec;
  --color-surface-alt: #e5e3e3;
  --color-surface-deep: #d9d7d7;
  --color-ink: #483e3c;
  --color-ink-soft: #716260;
  --color-ink-muted: #887977;
  --color-line: #cfcdcc;
  --color-primary: #c84b37;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #e8d5d3;
  --color-accent: #df2d10;
  --color-accent-ink: #ffffff;
  --color-highlight: #eacac4;
  --color-focus: #cd1f04;
  --color-contrast-surface: #1c1211;
  --color-contrast-ink: #e7e5e4;
  --color-contrast-line: #49403f;
  --color-contrast-accent: #ee381b;
  --overlay-scrim: linear-gradient(180deg, rgba(28, 18, 17, 0.35) 0%, rgba(28, 18, 17, 0.72) 55%, rgba(28, 18, 17, 0.92) 100%);
  --font-heading: "Kaiti SC", STKaiti, KaiTi, "Songti SC", serif;
  --font-body: "Songti SC", "PingFang SC", "Microsoft YaHei", serif;
  --font-mono: ui-monospace, Menlo, Consolas, monospace;
  --text-xs: 12.2px;
  --text-sm: 15.2px;
  --text-base: 17px;
  --text-lg: 21.2px;
  --text-xl: 26.6px;
  --text-2xl: 33.2px;
  --text-3xl: 41.5px;
  --text-4xl: 51.9px;
  --text-display: clamp(40px, 8.2vw, 105px);
  --text-figure: clamp(33px, 5.9vw, 76px);
  --weight-heading: 507;
  --weight-body: 400;
  --leading-body: 1.95;
  --leading-heading: 1.21;
  --tracking-heading: 0.012em;
  --radius-sm: 2px;
  --radius-md: 3px;
  --radius-lg: 4px;
  --radius-pill: 4px;
  --border-thin: 1px;
  --border-thick: 1px;
  --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: 1100px;
  --measure: 60ch;
  --gutter: 24px;
  --section-y: 106px;
  --section-y-lg: 148px;
}

/* ============ 1. reset ============ */
*,
*::before,
*::after { box-sizing: border-box; }

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

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;
}

h1, h2, h3, h4, h5, h6 {
  margin: 0 0 var(--space-3);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
}

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

p { margin: 0 0 var(--space-3); }
p:last-child { margin-bottom: 0; }

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

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

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

button, input, select, textarea { font: inherit; color: inherit; }

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

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

[id] { scroll-margin-top: 140px; }

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

/* ============ 2. 中文排版与数字 ============ */
.num,
time,
.data-cell__value,
.chapter-number,
.contact-value--mono,
.fee-amount,
.footer-legal,
.header-mail,
.footer-stamp,
[data-count] {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

/* ============ 3. 布局骨架 ============ */
.container {
  width: 100%;
  max-width: calc(var(--container) + var(--gutter) * 2);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }

.band-alt { background-color: var(--color-surface-alt); }
.band-deep { background-color: var(--color-surface-deep); }

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

.rule {
  height: 1px;
  margin: 0;
  border: 0;
  background-color: var(--color-line);
}
.rule--offset {
  width: calc(100% - var(--space-8));
  margin-left: var(--space-8);
}

/* ============ 4. 文字与标题组件 ============ */
.h-display {
  font-family: var(--font-heading);
  font-size: var(--text-display);
  font-weight: 600;
  line-height: 1.04;
  letter-spacing: 0.01em;
  color: var(--color-ink);
}

.title-xl { font-size: var(--text-3xl); }
.title-lg { font-size: var(--text-2xl); }
.title-md { font-size: var(--text-xl); }

.lede {
  max-width: var(--measure);
  font-size: var(--text-lg);
  line-height: 1.8;
  color: var(--color-ink-soft);
}

.prose { max-width: var(--measure); }
.prose p { margin-bottom: var(--space-3); color: var(--color-ink); }
.prose h2 { margin-top: var(--space-8); }
.prose h3 { margin-top: var(--space-4); }

.meta {
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  color: var(--color-ink-muted);
}

.mark {
  padding: 0 4px;
  background-color: var(--color-highlight);
  color: var(--color-ink);
  border-radius: var(--radius-sm);
}

.chapter-number {
  display: block;
  margin-bottom: var(--space-2);
  font-size: var(--text-figure);
  font-weight: 700;
  line-height: 0.9;
  letter-spacing: -0.02em;
  color: var(--color-primary);
}
.chapter-number--sm { font-size: var(--text-3xl); }

/* ============ 5. 按钮、标签、面包屑 ============ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px var(--space-3);
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  letter-spacing: 0.06em;
  line-height: 1.3;
  transition: background-color 160ms ease, color 160ms ease, border-color 160ms ease;
}

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

.btn--ghost {
  border-color: var(--color-line);
  color: var(--color-ink);
}
.btn--ghost:hover {
  border-color: var(--color-ink-soft);
  background-color: var(--color-surface-alt);
}

.btn--on-contrast {
  border-color: var(--color-contrast-line);
  color: var(--color-contrast-ink);
}
.btn--on-contrast:hover {
  border-color: var(--color-contrast-accent);
  color: var(--color-contrast-accent);
}

.tag {
  display: inline-block;
  padding: 2px 8px;
  background-color: var(--color-surface-deep);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-soft);
}
.tag--primary {
  background-color: var(--color-primary-soft);
  color: var(--color-primary);
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-block: var(--space-3);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}
.breadcrumb a {
  color: var(--color-ink-soft);
  border-bottom: var(--border-thin) solid var(--color-line);
}
.breadcrumb li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--color-line);
}

/* ============ 6. 数据组件 ============ */
.data-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: 1px;
  background-color: var(--color-line);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.data-cell {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: var(--space-2);
  background-color: var(--color-surface-alt);
}
.data-cell__label {
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  color: var(--color-ink-muted);
}
.data-cell__value {
  font-size: var(--text-lg);
  font-weight: 600;
  line-height: 1.1;
  color: var(--color-ink);
}
.data-cell__unit {
  margin-left: 4px;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 400;
  color: var(--color-ink-muted);
}
.data-cell--key { background-color: var(--color-surface-deep); }
.data-cell--key .data-cell__value { color: var(--color-accent); }

.split {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.65fr);
  gap: var(--space-6);
  align-items: start;
}

/* ============ 7. 叙述组件 ============ */
.entry {
  display: block;
  padding: var(--space-3) 0;
  border-top: var(--border-thin) solid var(--color-line);
}
.entry__title {
  margin-bottom: 6px;
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  line-height: var(--leading-heading);
  color: var(--color-ink);
}
.entry__meta {
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.05em;
  color: var(--color-ink-muted);
}
.entry__body {
  max-width: var(--measure);
  font-size: var(--text-sm);
  line-height: 1.85;
  color: var(--color-ink-soft);
}

.timeline {
  position: relative;
  padding-left: var(--space-4);
}
.timeline::before {
  content: "";
  position: absolute;
  left: 3px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background-color: var(--color-line);
}
.timeline__item {
  position: relative;
  padding-bottom: var(--space-4);
}
.timeline__item::before {
  content: "";
  position: absolute;
  left: calc(var(--space-4) * -1 + 1px);
  top: 9px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background-color: var(--color-ink-muted);
}
.timeline__item--flag::before { background-color: var(--color-accent); }

/* ============ 8. 图片容器 ============ */
.figure { display: block; margin: 0; }

.figure__frame {
  padding: var(--space-2);
  background-color: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
}

.figure__media {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  background-color: var(--color-surface-deep);
  border-radius: var(--radius-sm);
}
.figure__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.figure__caption {
  margin-top: var(--space-2);
  font-size: var(--text-xs);
  line-height: 1.7;
  color: var(--color-ink-muted);
}

.figure__overlay {
  position: absolute;
  inset: auto 0 0 0;
  padding: var(--space-3);
  background: var(--overlay-scrim);
  color: var(--color-contrast-ink);
  font-size: var(--text-sm);
  line-height: 1.6;
}

/* ============ 9. 头部 ============ */
.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 200;
  padding: 10px var(--space-3);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  transform: translateY(-180%);
  transition: transform 160ms ease;
}
.skip-link:focus { transform: none; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: color-mix(in srgb, var(--color-surface) 94%, transparent);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
}
.site-header::after {
  content: "";
  display: block;
  width: calc(100% - var(--space-8));
  height: 1px;
  margin-left: var(--space-8);
  background-color: var(--color-line);
}

.header-inner { padding-block: var(--space-3) var(--space-2); }

.header-band {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: var(--space-2) var(--space-6);
}

.brand-block {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.brand {
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: 0.12em;
  color: var(--color-ink);
  transition: color 160ms ease;
}
a.brand:hover { color: var(--color-primary); }

.brand-note {
  margin: 0;
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-ink-muted);
}

.header-tools {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  gap: var(--space-2) var(--space-4);
}

.search-field {
  display: flex;
  flex-direction: column;
  gap: 5px;
  flex: 1 1 238px;
  min-width: 220px;
  max-width: 320px;
}

.search-label {
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
}

.search-input {
  width: 100%;
  padding: 8px 12px;
  background-color: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  color: var(--color-ink);
  transition: border-color 160ms ease, background-color 160ms ease;
}
.search-input::placeholder { color: var(--color-ink-muted); }
.search-input:focus {
  background-color: var(--color-surface);
  border-color: var(--color-focus);
}

.search-hint {
  margin: 0;
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
}

.header-mail {
  padding-bottom: 2px;
  font-size: var(--text-xs);
  letter-spacing: 0.02em;
  color: var(--color-ink-soft);
  border-bottom: var(--border-thin) solid var(--color-line);
  transition: color 160ms ease, border-color 160ms ease;
}
.header-mail:hover {
  color: var(--color-primary);
  border-color: var(--color-primary);
}

.nav-band {
  position: relative;
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding-top: var(--space-2);
}
.nav-band::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 34%;
  height: 1px;
  background-color: var(--color-line);
}

.site-nav { flex: 1 1 auto; }

.nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  min-width: max-content;
}

.nav-list a {
  position: relative;
  display: inline-block;
  padding: 6px 0;
  font-size: var(--text-sm);
  letter-spacing: 0.06em;
  color: var(--color-ink-soft);
  transition: color 160ms ease;
}
.nav-list a::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background-color: currentColor;
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 160ms ease;
}
.nav-list a:hover { color: var(--color-ink); }
.nav-list a:hover::before { transform: scaleX(1); }

.nav-list li:nth-child(1) a { color: var(--color-ink); }
.nav-list li:nth-child(2) a { color: var(--color-ink-soft); font-weight: 500; }
.nav-list li:nth-child(3) a { color: var(--color-ink); }
.nav-list li:nth-child(4) a { color: var(--color-ink-muted); font-weight: 500; }
.nav-list li:nth-child(5) a { color: var(--color-ink-soft); }
.nav-list li:nth-child(6) a { color: var(--color-ink); font-weight: 500; }

.nav-list a[aria-current="page"] {
  color: var(--color-primary);
  font-weight: 600;
}
.nav-list a[aria-current="page"]::before {
  height: 2px;
  background-color: var(--color-primary);
  transform: scaleX(1);
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 7px 14px;
  background-color: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  letter-spacing: 0.08em;
  color: var(--color-ink);
  transition: border-color 160ms ease, color 160ms ease;
}
.nav-toggle::before {
  content: "";
  width: 13px;
  height: 9px;
  border-top: 1px solid currentColor;
  border-bottom: 1px solid currentColor;
}
.nav-toggle:hover { border-color: var(--color-ink-soft); }

/* ============ 10. 页脚 ============ */
.site-footer {
  margin-top: var(--section-y-lg);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.footer-inner { padding-block: var(--space-6) var(--space-8); }
.footer-inner::before {
  content: "";
  display: block;
  width: calc(100% - var(--space-6));
  height: 1px;
  margin-left: var(--space-6);
  margin-bottom: var(--space-8);
  background-color: var(--color-contrast-line);
}

.footer-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.45fr);
  gap: var(--space-6) var(--space-8);
  align-items: start;
}

.footer-col--brand {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.footer-brand {
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--color-contrast-ink);
}
.footer-brand:hover { color: var(--color-contrast-accent); }

.footer-stamp {
  margin: 0;
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: color-mix(in srgb, var(--color-contrast-ink) 62%, transparent);
}

.footer-note {
  max-width: 40ch;
  margin: 0;
  font-size: var(--text-sm);
  line-height: 1.85;
  color: color-mix(in srgb, var(--color-contrast-ink) 84%, transparent);
}
.footer-note--dim {
  font-size: var(--text-xs);
  color: color-mix(in srgb, var(--color-contrast-ink) 62%, transparent);
}
.footer-note a {
  color: color-mix(in srgb, var(--color-contrast-ink) 88%, transparent);
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
}
.footer-note a:hover {
  color: var(--color-contrast-accent);
  border-color: var(--color-contrast-accent);
}

.footer-col--fees {
  margin-top: var(--space-2);
  padding-left: var(--space-6);
  border-left: var(--border-thin) solid var(--color-contrast-line);
}

.footer-heading {
  margin-bottom: var(--space-3);
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--color-contrast-accent);
}

.fee-item { border-top: var(--border-thin) solid var(--color-contrast-line); }
.fee-item:last-of-type { border-bottom: var(--border-thin) solid var(--color-contrast-line); }

.fee-item > summary {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-3);
  padding: var(--space-2) 0;
  list-style: none;
  cursor: pointer;
  font-size: var(--text-sm);
  color: color-mix(in srgb, var(--color-contrast-ink) 86%, transparent);
  transition: color 160ms ease;
}
.fee-item > summary::-webkit-details-marker { display: none; }
.fee-item > summary::marker { content: ""; }
.fee-item > summary:hover { color: var(--color-contrast-ink); }
.fee-item[open] > summary { color: var(--color-contrast-ink); }

.fee-amount {
  font-size: var(--text-sm);
  letter-spacing: 0.02em;
  color: var(--color-contrast-accent);
  white-space: nowrap;
}

.fee-detail {
  max-width: 54ch;
  padding-bottom: var(--space-3);
  font-size: var(--text-sm);
  line-height: 1.85;
  color: color-mix(in srgb, var(--color-contrast-ink) 74%, transparent);
}

.footer-contact {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: var(--space-4) var(--space-6);
  margin-top: var(--space-8);
  padding-top: var(--space-6);
  border-top: var(--border-thin) solid var(--color-contrast-line);
}
.footer-contact > .contact-cell:nth-child(2) { margin-top: var(--space-4); }
.footer-contact > .contact-cell:nth-child(3) { margin-top: var(--space-2); }
.footer-contact > .contact-cell:nth-child(4) { margin-top: var(--space-6); }

.contact-label {
  margin-bottom: 6px;
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: 500;
  letter-spacing: 0.12em;
  color: color-mix(in srgb, var(--color-contrast-ink) 60%, transparent);
}

.contact-value {
  margin: 0;
  font-size: var(--text-sm);
  line-height: 1.8;
  color: var(--color-contrast-ink);
}
.contact-value a {
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
  transition: color 160ms ease, border-color 160ms ease;
}
.contact-value a:hover {
  color: var(--color-contrast-accent);
  border-color: var(--color-contrast-accent);
}
.contact-value--mono { letter-spacing: 0.04em; }

.contact-hint {
  margin: 6px 0 0;
  font-size: var(--text-xs);
  line-height: 1.7;
  color: color-mix(in srgb, var(--color-contrast-ink) 62%, transparent);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-3);
  margin-top: var(--space-6);
  padding-top: var(--space-4);
  border-top: var(--border-thin) solid var(--color-contrast-line);
  font-size: var(--text-xs);
  color: color-mix(in srgb, var(--color-contrast-ink) 66%, transparent);
}

.footer-legal {
  margin: 0;
  letter-spacing: 0.04em;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
}
.footer-links a {
  padding-bottom: 2px;
  color: color-mix(in srgb, var(--color-contrast-ink) 88%, transparent);
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
  transition: color 160ms ease, border-color 160ms ease;
}
.footer-links a:hover {
  color: var(--color-contrast-accent);
  border-color: var(--color-contrast-accent);
}

.to-top {
  position: fixed;
  right: var(--space-3);
  bottom: var(--space-3);
  z-index: 90;
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  opacity: 0;
  visibility: hidden;
  transform: translateY(6px);
  transition: opacity 240ms ease, visibility 240ms ease, transform 240ms ease,
    color 160ms ease, border-color 160ms ease;
}
.to-top[data-visible] {
  opacity: 1;
  visibility: visible;
  transform: none;
}
.to-top:hover {
  color: var(--color-contrast-accent);
  border-color: var(--color-contrast-accent);
}

/* ============ 11. 响应式 ============ */
@media (max-width: 900px) {
  .split { grid-template-columns: 1fr; gap: var(--space-4); }

  .nav-band {
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-2);
  }
  .nav-toggle {
    display: inline-flex;
    align-self: flex-start;
  }
  .site-nav {
    display: none;
    flex-basis: 100%;
  }
  .site-nav[data-open] { display: block; }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    min-width: 0;
  }
  .nav-list li { border-top: var(--border-thin) solid var(--color-line); }
  .nav-list li:last-child { border-bottom: var(--border-thin) solid var(--color-line); }
  .nav-list a {
    display: block;
    padding: 12px 0;
    font-size: var(--text-base);
  }
  .nav-list a::before { display: none; }
  .nav-list li:nth-child(n) a { color: var(--color-ink-soft); font-weight: 400; }
  .nav-list li:nth-child(odd) a { color: var(--color-ink); }
  .nav-list a[aria-current="page"] {
    padding-left: 12px;
    color: var(--color-primary);
    font-weight: 600;
  }
  .nav-list a[aria-current="page"]::after {
    content: "";
    position: absolute;
    left: 0;
    top: 14px;
    bottom: 14px;
    width: 2px;
    background-color: var(--color-primary);
  }

  .footer-grid { grid-template-columns: 1fr; gap: var(--space-6); }
  .footer-col--fees {
    margin-top: 0;
    padding-left: 0;
    padding-top: var(--space-4);
    border-left: 0;
    border-top: var(--border-thin) solid var(--color-contrast-line);
  }
  .footer-contact { margin-top: var(--space-6); padding-top: var(--space-4); }
  .footer-contact > .contact-cell { margin-top: 0 !important; }
}

@media (max-width: 640px) {
  .container { padding-inline: var(--space-2); }

  .section { padding-block: calc(var(--section-y) * 0.62); }
  .section--lg { padding-block: calc(var(--section-y-lg) * 0.6); }
  .site-footer { margin-top: calc(var(--section-y) * 0.8); }

  .header-inner { padding-block: var(--space-2) var(--space-1); }
  .brand { font-size: var(--text-xl); letter-spacing: 0.1em; }
  .header-tools { width: 100%; }
  .search-field { max-width: none; }

  .site-header::after { width: calc(100% - var(--space-2)); margin-left: var(--space-2); }
  .footer-inner::before { width: calc(100% - var(--space-3)); margin-left: var(--space-3); }

  .rule--offset { width: calc(100% - var(--space-4)); margin-left: var(--space-4); }

  .footer-inner { padding-block: var(--space-4) var(--space-6); }
  .to-top { right: var(--space-2); bottom: var(--space-2); }
}

/* ============ 12. 动效降级 ============ */
@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;
  }
  .to-top { transform: none; }
  .skip-link { transition: none; }
}