:root {
  --color-surface: #fcfcfc;
  --color-surface-alt: #f3f3f3;
  --color-surface-deep: #e6e7e7;
  --color-ink: #414d4c;
  --color-ink-soft: #637372;
  --color-ink-muted: #778886;
  --color-line: #dadcdc;
  --color-primary: #128179;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #dbebea;
  --color-accent: #ec0e1c;
  --color-accent-ink: #ffffff;
  --color-highlight: #f9d1d4;
  --color-focus: #e50110;
  --color-contrast-surface: #10201f;
  --color-contrast-ink: #e4e7e7;
  --color-contrast-line: #3f4c4b;
  --color-contrast-accent: #f43e4a;
  --overlay-scrim: linear-gradient(180deg, rgba(16, 32, 31, 0.35) 0%, rgba(16, 32, 31, 0.72) 55%, rgba(16, 32, 31, 0.92) 100%);
  --font-heading: ui-monospace, SFMono-Regular, Menlo, Consolas, "PingFang SC", monospace;
  --font-body: "PingFang SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --text-xs: 9.7px;
  --text-sm: 13.0px;
  --text-base: 15px;
  --text-lg: 20.0px;
  --text-xl: 26.7px;
  --text-2xl: 35.5px;
  --text-3xl: 47.4px;
  --text-4xl: 63.1px;
  --text-display: clamp(54px, 11.1vw, 142px);
  --text-figure: clamp(45px, 8.0vw, 102px);
  --weight-heading: 730;
  --weight-body: 400;
  --leading-body: 1.7;
  --leading-heading: 1.25;
  --tracking-heading: 0.036em;
  --radius-sm: 56px;
  --radius-md: 77px;
  --radius-lg: 98px;
  --radius-pill: 999px;
  --border-thin: 1px;
  --border-thick: 2px;
  --shadow-1: 0 0 0 1px rgba(236, 14, 28, 0.35);
  --shadow-2: 0 0 28px rgba(236, 14, 28, 0.35);
  --space-1: 6px;
  --space-2: 12px;
  --space-3: 18px;
  --space-4: 24px;
  --space-6: 36px;
  --space-8: 48px;
  --container: 1200px;
  --measure: 66ch;
  --gutter: 18px;
  --section-y: 75px;
  --section-y-lg: 105px;
}

/* ============ reset ============ */
*, *::before, *::after { box-sizing: border-box; }
html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 120px;
}
body {
  margin: 0;
  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;
  overflow-x: hidden;
}
img, svg, video { display: block; max-width: 100%; height: auto; }
h1, h2, h3, h4, h5 {
  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);
  color: var(--color-ink);
}
h1 { font-size: var(--text-4xl); }
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); max-width: var(--measure); }
ul, ol { margin: 0 0 var(--space-3); padding-left: 1.25em; }
li { margin-bottom: var(--space-1); }
strong { font-weight: var(--weight-heading); }
code, kbd, samp { font-family: var(--font-mono); font-size: 0.92em; }
hr { border: 0; border-top: var(--border-thin) dotted var(--color-line); margin: var(--space-8) 0; }
button { font: inherit; color: inherit; }
a { color: var(--color-primary); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { color: color-mix(in srgb, var(--color-primary) 68%, var(--color-contrast-surface)); }
:focus-visible {
  outline: var(--border-thick) solid var(--color-focus);
  outline-offset: 2px;
  border-radius: 4px;
}
::selection { background: var(--color-highlight); color: var(--color-ink); }

/* ============ 布局容器与栅格 ============ */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}
.container--wide { max-width: calc(var(--container) + var(--space-8) * 2); }
.grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
}
.span-1 { grid-column: span 1; }
.span-2 { grid-column: span 2; }
.span-3 { grid-column: span 3; }
.span-4 { grid-column: span 4; }
.span-5 { grid-column: span 5; }
.span-6 { grid-column: span 6; }
.span-7 { grid-column: span 7; }
.span-8 { grid-column: span 8; }
.span-9 { grid-column: span 9; }
.span-10 { grid-column: span 10; }
.span-11 { grid-column: span 11; }
.span-12 { grid-column: span 12; }
.stack { display: flex; flex-direction: column; gap: var(--space-3); }
.row { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-3); }
.row--between { justify-content: space-between; }
.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }

/* ============ 排版组件 ============ */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  margin: 0 0 var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}
.eyebrow::before {
  content: "";
  width: 22px;
  height: var(--border-thin);
  background: currentColor;
  opacity: 0.7;
  flex: none;
}
.mono { font-family: var(--font-mono); letter-spacing: 0.04em; }
.lede { font-size: var(--text-lg); color: var(--color-ink-soft); }
.vrule {
  border-left: var(--border-thick) solid var(--color-primary);
  padding-left: var(--space-4);
}
.vrule--accent { border-left-color: var(--color-accent); }
.prose { max-width: var(--measure); }
.prose > * + * { margin-top: var(--space-4); }
.prose h2 { font-size: var(--text-xl); margin-top: var(--space-8); }
.prose h3 { font-size: var(--text-lg); margin-top: var(--space-6); }
.prose p, .prose ul, .prose ol { max-width: var(--measure); }
.prose blockquote {
  margin: 0;
  padding: var(--space-3) var(--space-4);
  border-left: var(--border-thick) solid var(--color-primary);
  background: var(--color-primary-soft);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--color-ink-soft);
}
.dotted-sep { border: 0; border-top: var(--border-thin) dotted var(--color-line); margin: var(--space-8) 0; }
.index-chip {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 30px;
  padding: 3px var(--space-2);
  border-radius: var(--radius-pill);
  background: var(--color-surface-deep);
  border: var(--border-thin) solid var(--color-line);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-ink-muted);
  flex: none;
}

/* ============ 胶囊标签 / 状态条 / 按钮 ============ */
.tag {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 4px var(--space-3);
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid var(--color-line);
  background: var(--color-surface-alt);
  color: var(--color-ink-soft);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  white-space: nowrap;
}
.tag--primary {
  background: var(--color-primary-soft);
  border-color: color-mix(in srgb, var(--color-primary) 34%, transparent);
  color: color-mix(in srgb, var(--color-primary) 88%, var(--color-contrast-surface));
}
.tag--accent {
  background: var(--color-highlight);
  border-color: color-mix(in srgb, var(--color-accent) 32%, transparent);
  color: color-mix(in srgb, var(--color-accent) 84%, var(--color-contrast-surface));
}
.tag-row { display: flex; flex-wrap: wrap; gap: var(--space-1); margin: 0; padding: 0; list-style: none; }

.status-bar { display: inline-flex; align-items: center; gap: var(--space-2); }
.status-bar__track {
  width: 64px;
  height: 4px;
  border-radius: var(--radius-pill);
  background: var(--color-surface-deep);
  overflow: hidden;
  flex: none;
}
.status-bar__fill {
  display: block;
  height: 100%;
  width: var(--fill, 60%);
  border-radius: inherit;
  background: linear-gradient(90deg, var(--color-primary), color-mix(in srgb, var(--color-primary) 55%, var(--color-highlight)));
}
.status-bar__label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
  letter-spacing: 0.08em;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid transparent;
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  font-weight: var(--weight-heading);
  letter-spacing: 0.05em;
  text-decoration: none;
  cursor: pointer;
  transition: transform 180ms ease, box-shadow 180ms ease, background-color 180ms ease, color 180ms ease, border-color 180ms ease;
}
.btn--sm { padding: var(--space-2) var(--space-4); font-size: var(--text-xs); }
.btn--primary {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.34);
}
.btn--primary:hover {
  background: color-mix(in srgb, var(--color-primary) 84%, var(--color-contrast-surface));
  color: var(--color-primary-ink);
  transform: translateY(-2px);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.34), 0 12px 28px color-mix(in srgb, var(--color-primary) 30%, transparent);
}
.btn--accent {
  background: var(--color-accent);
  color: var(--color-accent-ink);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.34);
}
.btn--accent:hover {
  background: color-mix(in srgb, var(--color-accent) 86%, var(--color-contrast-surface));
  color: var(--color-accent-ink);
  transform: translateY(-2px);
  box-shadow: var(--shadow-2);
}
.btn--ghost {
  background: transparent;
  color: var(--color-primary);
  border-color: color-mix(in srgb, var(--color-primary) 45%, transparent);
}
.btn--ghost:hover {
  background: var(--color-primary-soft);
  color: color-mix(in srgb, var(--color-primary) 88%, var(--color-contrast-surface));
  transform: translateY(-2px);
}

/* ============ 面板 ============ */
.panel {
  background: var(--color-surface);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  padding: var(--space-6);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.92), 0 10px 30px color-mix(in srgb, var(--color-contrast-surface) 7%, transparent);
  transition: transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease;
}
.panel--inset { background: var(--color-surface-alt); }
.panel--deep {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-color: var(--color-contrast-line);
}
.panel--deep h1, .panel--deep h2, .panel--deep h3, .panel--deep h4 { color: var(--color-contrast-ink); }
.panel--deep p { color: color-mix(in srgb, var(--color-contrast-ink) 82%, transparent); }
.panel--glow { box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.92), var(--shadow-1), 0 14px 40px color-mix(in srgb, var(--color-accent) 14%, transparent); }
.panel--shift { margin-left: calc(var(--space-8) * -1); }
.panel--lift:hover {
  transform: translateY(-2px);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.92), 0 18px 44px color-mix(in srgb, var(--color-primary) 20%, transparent);
  border-color: color-mix(in srgb, var(--color-primary) 40%, transparent);
}

/* ============ 关键数字组 ============ */
.stat { display: flex; flex-direction: column; gap: var(--space-1); }
.stat__value {
  font-family: var(--font-mono);
  font-weight: var(--weight-heading);
  font-size: var(--text-figure);
  line-height: 0.86;
  letter-spacing: -0.03em;
  color: var(--color-primary);
}
.stat--accent .stat__value { color: var(--color-accent); }
.stat--deep .stat__value { color: var(--color-contrast-ink); }
.stat__unit {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
  letter-spacing: 0.06em;
}
.stat--deep .stat__unit { color: color-mix(in srgb, var(--color-contrast-ink) 62%, transparent); }
.stat__label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}

/* ============ 面包屑 ============ */
.breadcrumb { font-family: var(--font-mono); font-size: var(--text-xs); letter-spacing: 0.08em; color: var(--color-ink-muted); }
.breadcrumb ol { display: flex; flex-wrap: wrap; gap: var(--space-2); list-style: none; margin: 0; padding: 0; }
.breadcrumb li { display: inline-flex; align-items: center; margin: 0; }
.breadcrumb li:not(:last-child)::after { content: "···"; margin-left: var(--space-2); color: var(--color-line); letter-spacing: 0.1em; }
.breadcrumb a { color: var(--color-ink-soft); text-decoration: none; }
.breadcrumb a:hover { color: var(--color-primary); text-decoration: underline; }
.breadcrumb [aria-current="page"] { color: var(--color-ink); }

/* ============ 图片容器基础规则 ============ */
.media-frame {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-sm);
  border: var(--border-thin) solid var(--color-line);
  background: var(--color-surface-alt);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.9);
  isolation: isolate;
}
.media-frame > img { width: 100%; height: 100%; object-fit: cover; }
.media-frame--wide { aspect-ratio: 16 / 9; }
.media-frame--band { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 3 / 4; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame--placeholder {
  background-image:
    repeating-linear-gradient(135deg, color-mix(in srgb, var(--color-primary) 12%, transparent) 0 2px, transparent 2px 14px),
    linear-gradient(160deg, var(--color-surface-alt) 0%, var(--color-surface-deep) 100%);
}
.media-frame--placeholder::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 22% 18%, color-mix(in srgb, var(--color-primary) 26%, transparent) 0%, transparent 58%),
              radial-gradient(circle at 82% 76%, color-mix(in srgb, var(--color-accent) 18%, transparent) 0%, transparent 52%);
}
.media-frame--scrim::after {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--overlay-scrim);
  pointer-events: none;
}
.media-frame__caption {
  position: absolute;
  z-index: 2;
  left: var(--space-4);
  right: var(--space-4);
  bottom: var(--space-4);
  margin: 0;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  color: var(--color-contrast-ink);
  max-width: none;
}

/* ============ 头部 ============ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background: color-mix(in srgb, var(--color-surface) 90%, transparent);
  backdrop-filter: saturate(150%) blur(14px);
  -webkit-backdrop-filter: saturate(150%) blur(14px);
  border-bottom: var(--border-thin) dotted var(--color-line);
}
.site-header::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: var(--border-thin);
  background: linear-gradient(90deg, transparent 0%, color-mix(in srgb, var(--color-primary) 70%, transparent) 34%, color-mix(in srgb, var(--color-accent) 45%, transparent) 72%, transparent 100%);
  pointer-events: none;
}
.header-shell {
  position: relative;
  display: flex;
  align-items: center;
  gap: var(--space-4);
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding: var(--space-3) var(--gutter);
}
.skip-link {
  position: absolute;
  left: var(--space-3);
  top: calc(var(--space-1) * -12);
  z-index: 120;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-pill);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  text-decoration: none;
  transition: top 180ms ease;
}
.skip-link:focus-visible { top: var(--space-3); color: var(--color-contrast-ink); }

.brand-block { display: flex; align-items: center; gap: var(--space-3); margin-right: auto; min-width: 0; }
.brand-mark { display: inline-flex; align-items: center; gap: var(--space-2); text-decoration: none; flex: none; }
.brand-mark__glyph {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: var(--radius-pill);
  background: linear-gradient(158deg, color-mix(in srgb, var(--color-primary) 74%, #ffffff) 0%, var(--color-primary) 56%, color-mix(in srgb, var(--color-primary) 78%, var(--color-contrast-surface)) 100%);
  color: var(--color-primary-ink);
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  line-height: 1;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.6), 0 0 16px color-mix(in srgb, var(--color-primary) 34%, transparent);
  flex: none;
}
.brand-mark__text {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}
.brand-mark:hover .brand-mark__text { color: var(--color-primary); }
.brand-line {
  margin: 0;
  padding-left: var(--space-3);
  border-left: var(--border-thin) dotted var(--color-line);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.12em;
  color: var(--color-ink-muted);
  max-width: none;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid var(--color-line);
  background: var(--color-surface-alt);
  color: var(--color-ink);
  font-family: var(--font-heading);
  font-size: var(--text-xs);
  letter-spacing: 0.14em;
  cursor: pointer;
  flex: none;
  transition: background-color 180ms ease, border-color 180ms ease, transform 180ms ease;
}
.nav-toggle:hover { background: var(--color-primary-soft); border-color: color-mix(in srgb, var(--color-primary) 35%, transparent); }
.nav-toggle__bars { display: inline-flex; flex-direction: column; gap: 3px; width: 16px; flex: none; }
.nav-toggle__bars > span {
  display: block;
  height: 1.5px;
  border-radius: var(--radius-pill);
  background: var(--color-primary);
  transition: transform 180ms ease, opacity 180ms ease;
}
.nav-toggle__bars > span:nth-child(2) { width: 11px; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars > span:nth-child(1) { transform: translateY(4.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars > span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars > span:nth-child(3) { transform: translateY(-4.5px) rotate(-45deg); }

.site-nav { display: flex; align-items: center; gap: var(--space-4); min-width: 0; }
.site-nav__head {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  margin: 0;
  padding: 4px var(--space-3);
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid var(--color-line);
  background: var(--color-surface-alt);
  max-width: none;
  flex: none;
}
.site-nav__meta {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  color: var(--color-ink-muted);
  white-space: nowrap;
}
.status-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: var(--radius-pill);
  background: var(--color-primary);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-primary) 20%, transparent);
  animation: dot-breathe 3s ease-in-out infinite;
  flex: none;
}
.status-dot--accent {
  background: var(--color-contrast-accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-contrast-accent) 22%, transparent);
}
@keyframes dot-breathe {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.42; transform: scale(0.8); }
}

.nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  margin: 0;
  padding: 0;
  list-style: none;
}
.nav-list > li { margin: 0; }
.nav-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 5px var(--space-3);
  border-radius: var(--radius-pill);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  line-height: 1.5;
  color: var(--color-ink-soft);
  text-decoration: none;
  white-space: nowrap;
  transition: background-color 180ms ease, color 180ms ease, box-shadow 180ms ease;
}
.nav-link:hover {
  background: var(--color-primary-soft);
  color: color-mix(in srgb, var(--color-primary) 88%, var(--color-contrast-surface));
}
.nav-link[aria-current="page"] {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.35);
}
.nav-link::after {
  content: attr(data-index);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  color: var(--color-ink-muted);
  display: none;
}
.nav-link[aria-current="page"]::after { color: color-mix(in srgb, var(--color-primary-ink) 72%, transparent); }

.nav-entries { display: flex; align-items: center; gap: var(--space-2); flex: none; }
.nav-entry {
  display: inline-flex;
  align-items: center;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid color-mix(in srgb, var(--color-primary) 32%, transparent);
  background: var(--color-primary-soft);
  color: color-mix(in srgb, var(--color-primary) 90%, var(--color-contrast-surface));
  font-family: var(--font-heading);
  font-size: var(--text-xs);
  font-weight: var(--weight-heading);
  letter-spacing: 0.05em;
  text-decoration: none;
  white-space: nowrap;
  transition: background-color 180ms ease, color 180ms ease, transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease;
}
.nav-entry:hover {
  background: var(--color-primary);
  border-color: transparent;
  color: var(--color-primary-ink);
  transform: translateY(-2px);
  box-shadow: 0 10px 24px color-mix(in srgb, var(--color-primary) 30%, transparent);
}
.nav-entry--accent {
  background: var(--color-accent);
  border-color: transparent;
  color: var(--color-accent-ink);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.34);
}
.nav-entry--accent:hover {
  background: color-mix(in srgb, var(--color-accent) 86%, var(--color-contrast-surface));
  color: var(--color-accent-ink);
  box-shadow: var(--shadow-2);
}

.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: color-mix(in srgb, var(--color-primary) 12%, transparent);
  overflow: hidden;
  pointer-events: none;
}
.scroll-progress__fill {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--color-primary) 0%, color-mix(in srgb, var(--color-primary) 55%, var(--color-accent)) 76%, var(--color-accent) 100%);
}

/* ============ 页脚 ============ */
.site-footer {
  position: relative;
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-top: var(--border-thin) solid var(--color-contrast-line);
}
.site-footer::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 2px;
  background: linear-gradient(90deg, var(--color-contrast-accent) 0%, color-mix(in srgb, var(--color-primary) 62%, transparent) 40%, transparent 92%);
  pointer-events: none;
}
.footer-shell {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2) var(--space-6);
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding: var(--space-4) var(--gutter);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
}
.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  margin: 0;
  max-width: none;
  font-family: var(--font-heading);
  font-size: var(--text-xs);
  letter-spacing: var(--tracking-heading);
  color: var(--color-contrast-ink);
}
.footer-links { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-4); margin-left: auto; }
.footer-contact { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-4); margin: 0; max-width: none; }
.footer-legal { margin: 0; max-width: none; color: color-mix(in srgb, var(--color-contrast-ink) 54%, transparent); }
.footer-link {
  color: color-mix(in srgb, var(--color-contrast-ink) 78%, transparent);
  text-decoration: none;
  border-bottom: var(--border-thin) dotted color-mix(in srgb, var(--color-contrast-ink) 38%, transparent);
  padding-bottom: 2px;
  transition: color 180ms ease, border-color 180ms ease;
}
.footer-link:hover, .footer-link:focus-visible {
  color: var(--color-contrast-accent);
  border-bottom-color: var(--color-contrast-accent);
}

/* ============ 显现动画 ============ */
.js-enabled [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
}
.js-enabled [data-reveal][data-reveal-visible] {
  opacity: 1;
  transform: none;
  transition: opacity 220ms ease, transform 220ms ease;
}

/* ============ 平板 ============ */
@media (max-width: 1180px) {
  .site-nav { gap: var(--space-3); }
  .nav-list { gap: 2px; }
  .nav-link { padding: 5px var(--space-2); }
  .brand-line { display: none; }
}

/* ============ 移动端导航 ============ */
@media (max-width: 1040px) {
  .nav-toggle { display: inline-flex; }
  .site-nav {
    position: absolute;
    top: calc(100% + var(--space-2));
    left: var(--gutter);
    right: var(--gutter);
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-3);
    max-height: min(74vh, 620px);
    overflow-y: auto;
    padding: var(--space-4);
    border: var(--border-thin) solid var(--color-line);
    border-radius: var(--radius-md);
    background: var(--color-surface);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.94), 0 24px 60px color-mix(in srgb, var(--color-contrast-surface) 18%, transparent);
  }
  .site-nav[data-open] { display: flex; }
  .site-nav__head {
    justify-content: flex-start;
    padding: 0 0 var(--space-3);
    border: 0;
    border-bottom: var(--border-thin) dotted var(--color-line);
    border-radius: 0;
    background: transparent;
  }
  .nav-list { flex-direction: column; align-items: stretch; gap: var(--space-1); }
  .nav-link {
    justify-content: space-between;
    padding: var(--space-3) var(--space-4);
    border-radius: var(--radius-pill);
    font-size: var(--text-base);
    border: var(--border-thin) solid var(--color-line);
    background: var(--color-surface-alt);
  }
  .nav-link::after { display: inline; }
  .nav-link[aria-current="page"] { border-color: transparent; }
  .nav-entries { flex-direction: column; align-items: stretch; gap: var(--space-2); }
  .nav-entry { justify-content: space-between; padding: var(--space-3) var(--space-4); font-size: var(--text-sm); }
}

@media (max-width: 900px) {
  .grid { grid-template-columns: repeat(6, minmax(0, 1fr)); }
  [class*="span-"] { grid-column: 1 / -1; }
  .span-3, .span-4 { grid-column: span 3; }
  .section { padding-block: calc(var(--section-y) * 0.72); }
  .section--lg { padding-block: calc(var(--section-y-lg) * 0.72); }
  .panel { padding: var(--space-4); border-radius: var(--radius-sm); }
  .panel--shift { margin-left: 0; }
  h1 { font-size: var(--text-3xl); }
  h2 { font-size: var(--text-xl); }
  .lede { font-size: var(--text-base); }
}

@media (max-width: 620px) {
  .header-shell { padding: var(--space-2) var(--gutter); }
  .brand-mark__text { font-size: var(--text-base); }
  .footer-shell { flex-direction: column; align-items: flex-start; gap: var(--space-2); }
  .footer-links, .footer-contact { margin-left: 0; }
  .footer-link { word-break: break-all; }
  .btn { width: 100%; }
}

/* ============ 无障碍与减动 ============ */
@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;
  }
  .status-dot { animation: none; }
  .js-enabled [data-reveal] { opacity: 1 !important; transform: none !important; }
}
@media print {
  .site-header, .site-footer, .scroll-progress { display: none; }
}