/* ==========================================================================
   8868看台 — /assets/site.css
   共享外壳：reset / 变量 / 中文排版 / 头部 / 页脚 / 通用组件
   ========================================================================== */

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

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

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

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

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

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

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

/* ---------- 2. 变量 ---------- */
:root {
  --ink: #0B1F1A;
  --ink-deep: #07130F;
  --moss: #244A3B;
  --cyan: #35F0C8;
  --orange: #F0763A;
  --yellow: #FFD447;
  --stone: #6E7A76;
  --cool: #A8B3AF;
  --cream: #F3F0E7;
  --clay: #B4593C;
  --white: #FFFFFF;

  --line: rgba(110, 122, 118, 0.45);
  --line-soft: rgba(110, 122, 118, 0.22);
  --grid-line: rgba(110, 122, 118, 0.12);
  --cyan-soft: rgba(53, 240, 200, 0.12);

  --shell: 1240px;
  --gutter: clamp(16px, 4vw, 40px);
  --capsule: 999px;
  --edge: 2px;

  --font-head: "Source Serif 4", "Source Serif Pro", "Noto Serif SC", "Songti SC", "SimSun", Georgia, serif;
  --font-label: "Archivo Narrow", "Oswald", "Arial Narrow", "Noto Sans SC", system-ui, sans-serif;
  --font-body: "Inter", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", "Roboto Mono", "SFMono-Regular", ui-monospace, Menlo, Consolas, monospace;

  --dur: 0.26s;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

/* ---------- 3. 基础排版 ---------- */
html { scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}

body {
  min-height: 100%;
  background-color: var(--ink);
  background-image:
    linear-gradient(to right, var(--grid-line) 1px, transparent 1px),
    linear-gradient(to bottom, var(--grid-line) 1px, transparent 1px);
  background-size: 80px 80px;
  color: var(--cream);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  letter-spacing: 0.005em;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 {
  font-family: var(--font-head);
  font-weight: 600;
  line-height: 1.25;
  color: var(--cream);
}

h1 { font-size: clamp(30px, 5vw, 44px); }
h2 { font-size: clamp(24px, 3.4vw, 32px); }
h3 { font-size: clamp(19px, 2.2vw, 24px); }

p { max-width: 42ch; }

strong { color: var(--cream); font-weight: 600; }

::selection { background: var(--cyan); color: var(--ink); }

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

html.is-nav-open,
html.is-nav-open body { overflow: hidden; }

#main-content { display: block; scroll-margin-top: 96px; }

/* ---------- 4. 跳转链接 ---------- */
.skip-link {
  position: fixed;
  top: -80px;
  left: 12px;
  z-index: 200;
  padding: 11px 18px;
  background: var(--cyan);
  color: var(--ink);
  font-family: var(--font-label);
  font-size: 13px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  border-radius: var(--edge);
  transition: top 0.2s ease;
}

.skip-link:focus { top: 12px; }

/* ---------- 5. 头部 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background: rgba(11, 31, 26, 0.92);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line-soft);
}

.hdr-grid {
  width: min(100%, calc(var(--shell) + var(--gutter) * 2));
  margin-inline: auto;
  padding: 10px var(--gutter);
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: clamp(12px, 2vw, 28px);
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}

.brand__mark {
  position: relative;
  flex: none;
  width: 36px;
  height: 36px;
  background:
    linear-gradient(135deg, var(--cyan) 0 47%, var(--moss) 47% 53%, var(--orange) 53% 100%);
  box-shadow: inset 0 0 0 1px rgba(243, 240, 231, 0.18);
}

.brand__mark::after {
  content: "";
  position: absolute;
  inset: 7px;
  border: 1px solid rgba(11, 31, 26, 0.6);
}

.brand__text { display: grid; gap: 1px; min-width: 0; }

.brand__name {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 19px;
  line-height: 1.2;
  color: var(--cream);
  letter-spacing: 0.01em;
}

.brand__tagline {
  font-family: var(--font-label);
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cool);
  white-space: nowrap;
}

.brand--footer .brand__mark { width: 40px; height: 40px; }
.brand--footer .brand__name { font-size: 21px; }

/* 胶囊导航 */
.nav {
  justify-self: center;
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 5px;
  border: 1px solid var(--line);
  border-radius: var(--capsule);
  background: rgba(36, 74, 59, 0.55);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.nav__label { display: none; }

.nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.nav__item { display: block; }

.nav__link {
  display: block;
  position: relative;
  padding: 8px 14px;
  border: 1px solid transparent;
  border-radius: var(--capsule);
  font-family: var(--font-label);
  font-size: 13px;
  letter-spacing: 0.09em;
  color: var(--cool);
  white-space: nowrap;
  transition: color var(--dur) ease, background-color var(--dur) ease, border-color var(--dur) ease;
}

.nav__link:hover {
  color: var(--cream);
  background: rgba(11, 31, 26, 0.6);
  border-color: var(--line-soft);
}

.nav__link[aria-current="page"] {
  color: var(--cyan);
  background: var(--cyan-soft);
  border-color: var(--cyan);
}

.nav__link:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 2px;
}

.nav__meta { display: none; }

/* 右侧工具区 */
.hdr-tools {
  display: flex;
  align-items: center;
  gap: 16px;
}

.hdr-stamp {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0;
  max-width: none;
  padding-left: 16px;
  border-left: 1px solid var(--line);
  font-family: var(--font-label);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cool);
}

.hdr-stamp__dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--cyan);
  animation: stamp-pulse 2.6s ease-in-out infinite;
}

.hdr-stamp__label { color: var(--stone); }

.hdr-stamp__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.04em;
  color: var(--cream);
}

@keyframes stamp-pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.4; transform: scale(0.78); }
}

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 9px 15px;
  border: 1px solid var(--line);
  border-radius: var(--capsule);
  background: rgba(36, 74, 59, 0.6);
  color: var(--cream);
  font-family: var(--font-label);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  cursor: pointer;
  transition: border-color var(--dur) ease, color var(--dur) ease;
}

.nav-toggle:hover { border-color: var(--cyan); color: var(--cyan); }

.nav-toggle__bars { display: grid; gap: 4px; width: 16px; }

.nav-toggle__bars span {
  display: block;
  height: 1.5px;
  background: var(--cyan);
}

/* ---------- 6. 页脚 ---------- */
.site-footer {
  margin-top: clamp(56px, 8vw, 104px);
  border-top: 1px solid var(--line);
  background:
    linear-gradient(180deg, rgba(36, 74, 59, 0.4), rgba(7, 19, 15, 0.94)),
    var(--ink-deep);
  color: var(--cool);
}

.ftr-grid {
  width: min(100%, calc(var(--shell) + var(--gutter) * 2));
  margin-inline: auto;
  padding: clamp(40px, 6vw, 76px) var(--gutter) 0;
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: clamp(28px, 4vw, 56px);
  align-items: start;
}

.ftr-brand__line {
  margin: 18px 0 10px;
  max-width: 30ch;
  font-family: var(--font-head);
  font-size: 19px;
  line-height: 1.6;
  color: var(--cream);
}

.ftr-brand__meta {
  margin: 0;
  max-width: 34ch;
  font-size: 13px;
  line-height: 1.7;
  color: var(--stone);
}

.ftr-col { min-width: 0; }

.ftr-col__title {
  margin: 0 0 16px;
  font-family: var(--font-label);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--cyan);
}

.ftr-links { display: grid; gap: 10px; }

.ftr-link {
  display: inline-block;
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
  font-size: 15px;
  color: var(--cool);
  transition: color var(--dur) ease, border-color var(--dur) ease;
}

.ftr-link:hover { color: var(--cyan); border-bottom-color: var(--cyan); }

.ftr-contact {
  width: min(100%, calc(var(--shell) + var(--gutter) * 2));
  margin: clamp(32px, 5vw, 64px) auto 0;
  padding: clamp(24px, 3vw, 38px) var(--gutter) 0;
  border-top: 1px solid var(--line-soft);
}

.ftr-contact__list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 14px 32px;
}

.ftr-contact__item {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 12px;
  align-items: baseline;
  padding-left: 14px;
  border-left: 1px solid var(--line-soft);
}

.ftr-contact__key {
  font-family: var(--font-label);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--stone);
}

.ftr-contact__val {
  font-size: 15px;
  line-height: 1.7;
  color: var(--cream);
  word-break: break-word;
}

.ftr-contact__val--mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 14px;
  letter-spacing: 0.02em;
}

.ftr-base {
  width: min(100%, calc(var(--shell) + var(--gutter) * 2));
  margin: clamp(28px, 4vw, 48px) auto 0;
  padding: 20px var(--gutter);
  border-top: 1px solid var(--line-soft);
  display: flex;
  flex-wrap: wrap;
  gap: 10px 28px;
  align-items: center;
  justify-content: space-between;
  font-family: var(--font-label);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--stone);
}

.ftr-base__copy { margin: 0; max-width: none; }

.ftr-base__icp {
  margin: 0;
  max-width: none;
  font-family: var(--font-mono);
  letter-spacing: 0.04em;
  color: var(--cool);
}

/* ---------- 7. 通用布局 ---------- */
.wrap {
  width: min(100%, calc(var(--shell) + var(--gutter) * 2));
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.wrap--narrow { max-width: 880px; }

.section { padding-block: clamp(48px, 7vw, 96px); }

.section--tight { padding-block: clamp(32px, 4vw, 56px); }

.section--band {
  background: linear-gradient(180deg, rgba(36, 74, 59, 0.5), rgba(36, 74, 59, 0.18));
  border-block: 1px solid var(--line-soft);
}

.section__head {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.5fr);
  gap: clamp(20px, 4vw, 48px);
  align-items: end;
  margin-bottom: clamp(24px, 4vw, 44px);
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0;
  max-width: none;
  font-family: var(--font-label);
  font-size: 11px;
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: var(--cyan);
}

.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: var(--cyan);
}

.section-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--stone);
}

.section-title {
  margin: 0.35em 0 0;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: clamp(26px, 3.4vw, 40px);
  line-height: 1.22;
  color: var(--cream);
}

.lede {
  margin: 0;
  max-width: 42ch;
  font-size: 17px;
  line-height: 1.8;
  color: var(--cool);
}

.prose { max-width: 42ch; color: var(--cool); }

.prose p { margin: 0 0 1.2em; }

.grid {
  display: grid;
  gap: clamp(16px, 2.4vw, 28px);
}

.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--split { grid-template-columns: minmax(0, 4fr) minmax(0, 8fr); }
.grid--split-rev { grid-template-columns: minmax(0, 8fr) minmax(0, 4fr); }

/* ---------- 8. 按钮 ---------- */
.btn {
  --btn-bg: transparent;
  --btn-fg: var(--cream);
  --btn-bd: var(--line);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  border: 1px solid var(--btn-bd);
  border-radius: var(--edge);
  background: var(--btn-bg);
  color: var(--btn-fg);
  font-family: var(--font-label);
  font-size: 13px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  cursor: pointer;
  transition: transform 0.18s ease, background-color var(--dur) ease,
    color var(--dur) ease, border-color var(--dur) ease;
}

.btn:hover { transform: translateY(-2px); }

.btn--primary {
  --btn-bg: var(--cyan);
  --btn-fg: var(--ink);
  --btn-bd: var(--cyan);
}

.btn--primary:hover {
  --btn-bg: var(--cream);
  --btn-bd: var(--cream);
}

.btn--ghost {
  --btn-fg: var(--cyan);
  --btn-bd: rgba(53, 240, 200, 0.55);
}

.btn--ghost:hover {
  --btn-bg: var(--cyan-soft);
  --btn-bd: var(--cyan);
}

.btn--quiet {
  --btn-fg: var(--cool);
  --btn-bd: var(--line);
}

.btn--quiet:hover {
  --btn-fg: var(--cream);
  --btn-bd: var(--cool);
}

.btn--sm {
  padding: 7px 15px;
  font-size: 12px;
}

/* ---------- 9. 卡片 / 数据 ---------- */
.card {
  position: relative;
  padding: clamp(18px, 2.2vw, 26px);
  border: 1px solid var(--line-soft);
  border-radius: var(--edge);
  background: rgba(36, 74, 59, 0.34);
  transition: transform 0.22s ease, border-color 0.22s ease, background-color 0.22s ease;
}

.card:hover {
  transform: translateY(-3px);
  border-color: rgba(53, 240, 200, 0.45);
  background: rgba(36, 74, 59, 0.5);
}

.card:focus-within { border-color: var(--cyan); }

.card--board { background: rgba(7, 19, 15, 0.62); }

.card__label {
  display: block;
  margin: 0 0 12px;
  font-family: var(--font-label);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--stone);
}

.card__title {
  margin: 0 0 10px;
  font-family: var(--font-head);
  font-size: 20px;
  line-height: 1.35;
  color: var(--cream);
}

.card__note {
  margin: 0;
  max-width: 42ch;
  font-size: 14px;
  line-height: 1.7;
  color: var(--cool);
}

.card__foot {
  margin-top: 16px;
  padding-top: 12px;
  border-top: 1px solid var(--line-soft);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.02em;
  color: var(--stone);
}

.stat { display: grid; gap: 6px; }

.stat__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 600;
  font-size: clamp(2.4rem, 6vw, 4.6rem);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--white);
}

.stat__value--accent { color: var(--yellow); }
.stat__value--cyan { color: var(--cyan); }

.stat__label {
  font-family: var(--font-label);
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cool);
}

.stat__delta {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  color: var(--orange);
}

/* ---------- 10. 数据条 ---------- */
.data-bar { display: grid; gap: 8px; }

.data-bar__meta {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  font-family: var(--font-label);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--cool);
}

.data-bar__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0;
  text-transform: none;
  color: var(--yellow);
}

.data-bar__track {
  height: 6px;
  border: 1px solid var(--line-soft);
  background: rgba(110, 122, 118, 0.18);
}

.data-bar__fill {
  display: block;
  height: 100%;
  width: var(--bar, 0%);
  background: linear-gradient(90deg, var(--cyan), rgba(53, 240, 200, 0.3));
  transition: width 0.6s var(--ease);
}

.data-bar__fill--orange {
  background: linear-gradient(90deg, var(--orange), rgba(240, 118, 58, 0.28));
}

.js-ready .data-bar__fill { width: 0; }
.js-ready .data-bar__fill.is-visible { width: var(--bar, 0%); }

/* ---------- 11. 时间轴 / 标签 / 表格 / 筛选 ---------- */
.timeline {
  border-left: 1px solid var(--line);
}

.timeline__item {
  position: relative;
  padding: 0 0 24px 22px;
}

.timeline__item::before {
  content: "";
  position: absolute;
  left: -4px;
  top: 9px;
  width: 7px;
  height: 7px;
  background: var(--orange);
}

.timeline__item--now::before {
  background: var(--cyan);
  box-shadow: 0 0 0 3px rgba(53, 240, 200, 0.18);
}

.timeline__time {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  color: var(--stone);
}

.timeline__text {
  margin: 4px 0 0;
  max-width: 42ch;
  font-size: 15px;
  line-height: 1.7;
  color: var(--cream);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  border: 1px solid var(--line);
  border-radius: var(--edge);
  font-family: var(--font-label);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--cool);
}

.tag--cyan { color: var(--cyan); border-color: rgba(53, 240, 200, 0.5); }
.tag--orange { color: var(--orange); border-color: rgba(240, 118, 58, 0.5); }
.tag--clay { color: var(--cream); background: var(--clay); border-color: var(--clay); }

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 15px;
}

.data-table th,
.data-table td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: 1px solid var(--line-soft);
}

.data-table thead th {
  font-family: var(--font-label);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cool);
  border-bottom-color: var(--line);
}

.data-table td.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  color: var(--yellow);
}

.data-table tbody tr:hover { background: rgba(53, 240, 200, 0.06); }

.filter {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.filter__btn {
  padding: 7px 14px;
  border: 1px solid var(--line);
  border-radius: var(--edge);
  background: transparent;
  color: var(--cool);
  font-family: var(--font-label);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  cursor: pointer;
  transition: color var(--dur) ease, border-color var(--dur) ease, background-color var(--dur) ease;
}

.filter__btn:hover { color: var(--cream); border-color: var(--cyan); }

.filter__btn[aria-pressed="true"] {
  color: var(--ink);
  background: var(--yellow);
  border-color: var(--yellow);
}

/* ---------- 12. 图片容器 ---------- */
.figure { display: grid; gap: 10px; }

.figure__media {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border: 1px solid var(--line-soft);
  background: linear-gradient(135deg, rgba(36, 74, 59, 0.6), rgba(7, 19, 15, 0.92));
}

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

.figure__media::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(180deg, transparent 45%, rgba(7, 19, 15, 0.72));
}

.figure__media--wide { aspect-ratio: 21 / 9; }
.figure__media--portrait { aspect-ratio: 3 / 4; }
.figure__media--square { aspect-ratio: 1 / 1; }

.figure__caption {
  font-size: 13px;
  line-height: 1.7;
  color: var(--stone);
}

/* ---------- 13. 面包屑 ---------- */
.breadcrumb {
  width: min(100%, calc(var(--shell) + var(--gutter) * 2));
  margin-inline: auto;
  padding: 18px var(--gutter) 0;
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-label);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--stone);
}

.breadcrumb__link { color: var(--cool); }
.breadcrumb__link:hover { color: var(--cyan); }
.breadcrumb__sep { color: var(--stone); }
.breadcrumb__current { color: var(--cream); }

/* ---------- 14. 滚动与显现 ---------- */
.progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 90;
  width: 100%;
  height: 2px;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--cyan), var(--yellow));
  pointer-events: none;
}

.to-top {
  position: fixed;
  right: clamp(14px, 3vw, 28px);
  bottom: clamp(14px, 3vw, 28px);
  z-index: 70;
  width: 44px;
  height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(53, 240, 200, 0.5);
  border-radius: var(--edge);
  background: rgba(7, 19, 15, 0.88);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 16px;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.24s ease, visibility 0.24s ease, transform 0.2s ease;
}

.to-top.is-visible { opacity: 1; visibility: visible; }
.to-top:hover { transform: translateY(-3px); border-color: var(--cyan); }

.js-ready [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

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

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- 15. 响应式 ---------- */
@media (max-width: 1080px) {
  .ftr-grid { grid-template-columns: 1.4fr 1fr 1fr; }
  .ftr-brand { grid-column: 1 / -1; }
}

@media (max-width: 900px) {
  body { font-size: 16px; }
  .grid--2,
  .grid--3,
  .grid--4,
  .grid--split,
  .grid--split-rev { grid-template-columns: minmax(0, 1fr); }
  .section__head { grid-template-columns: minmax(0, 1fr); align-items: start; }
}

@media (max-width: 1020px) {
  .hdr-grid {
    grid-template-columns: minmax(0, 1fr) auto;
    position: relative;
    z-index: 83;
  }

  .nav-toggle { display: inline-flex; }

  .hdr-tools { display: none; }

  .nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    left: auto;
    z-index: 82;
    width: min(86vw, 360px);
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 82px 20px 28px;
    border: 0;
    border-left: 1px solid var(--line);
    border-radius: 0;
    background: var(--ink-deep);
    overflow-y: auto;
    transform: translateX(102%);
    visibility: hidden;
    transition: transform 0.3s var(--ease), visibility 0.3s var(--ease);
  }

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

  .site-header[data-open]::after {
    content: "";
    position: fixed;
    inset: 0;
    z-index: 81;
    background: rgba(4, 12, 10, 0.72);
  }

  .nav__label {
    display: block;
    margin: 0 0 12px;
    font-family: var(--font-label);
    font-size: 11px;
    letter-spacing: 0.24em;
    text-transform: uppercase;
    color: var(--stone);
  }

  .nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    margin-bottom: 24px;
  }

  .nav__item { display: block; }

  .nav__link {
    padding: 14px 12px;
    border: 0;
    border-bottom: 1px solid var(--line-soft);
    border-radius: 0;
    font-size: 16px;
    letter-spacing: 0.06em;
  }

  .nav__link[aria-current="page"] {
    border-bottom-color: var(--cyan);
    border-left: 3px solid var(--cyan);
    padding-left: 9px;
  }

  .nav__meta {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: auto;
    padding-top: 20px;
    border-top: 1px solid var(--line);
  }

  .nav__meta-item {
    font-family: var(--font-label);
    font-size: 11px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--cool);
  }

  .nav__meta .btn { width: 100%; }
}

@media (max-width: 720px) {
  .ftr-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .ftr-brand { grid-column: 1 / -1; }
  .ftr-base { flex-direction: column; align-items: flex-start; gap: 8px; }
  .ftr-contact__item { grid-template-columns: minmax(0, 1fr); gap: 2px; }
}

@media (max-width: 520px) {
  .brand__tagline { display: none; }
  .brand--footer .brand__tagline { display: block; }
  .ftr-grid { grid-template-columns: minmax(0, 1fr); }
  .hdr-grid { padding-block: 8px; }
}

/* ---------- 16. 无障碍动效降级 ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

  .btn:hover,
  .card:hover,
  .to-top:hover { transform: none; }

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

  .js-ready .data-bar__fill { width: var(--bar, 0%); }
}