/* ============================================================
   完美体育最新版 · 共享层 /assets/site.css
   深夜球场绿底 + 岩灰精密网格 + 等宽索引 + 框景与刻度
   ============================================================ */

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

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

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

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

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

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

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

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

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

table { border-collapse: collapse; }

/* ---------- 2. 变量 ---------- */
:root {
  --pitch-950: #08150F;
  --pitch-850: #0F241A;
  --pitch-800: #0B1B12;
  --moss-600: #3F6B4E;
  --rock-500: #8A8F88;
  --clay-500: #B6724C;
  --bone-50: #F3EFE6;
  --amber-signal: #FF7A1A;
  --electric-500: #34C6FF;
  --lime-state: #A9E34B;
  --red-state: #FF5A5F;

  --line: rgba(138, 143, 136, 0.30);
  --line-strong: rgba(138, 143, 136, 0.52);

  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
  --font-mono: ui-monospace, "JetBrains Mono", "Noto Sans Mono", "Courier New", monospace;

  --fs-body: 16px;
  --shell: 1280px;
  --gutter: 24px;
  --header-h: 78px;

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

/* ---------- 3. 基础排版 ---------- */
body {
  min-height: 100%;
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: 1.85;
  color: var(--bone-50);
  background-color: var(--pitch-950);
  background-image:
    linear-gradient(to right, rgba(138, 143, 136, 0.055) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(138, 143, 136, 0.055) 1px, transparent 1px);
  background-size: 96px 96px, 96px 96px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3 {
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.22;
  text-align: left;
}

h4 { font-weight: 700; line-height: 1.4; }

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

.eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--rock-500);
  text-transform: uppercase;
}

.lede {
  max-width: 40em;
  font-size: clamp(17px, 1.5vw, 19px);
  line-height: 1.8;
  color: rgba(243, 239, 230, 0.90);
}

.prose {
  max-width: 38em;
  font-size: 17px;
  color: rgba(243, 239, 230, 0.82);
}

.prose p + p { margin-top: 1em; }

.prose strong { color: var(--bone-50); font-weight: 700; }

.prose a { border-bottom: 1px solid var(--electric-500); }

.link {
  color: var(--electric-500);
  border-bottom: 1px solid rgba(52, 198, 255, 0.5);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.link:hover { color: var(--amber-signal); border-bottom-color: var(--amber-signal); }

::selection { background: var(--amber-signal); color: var(--pitch-950); }

:focus-visible {
  outline: 2px solid var(--electric-500);
  outline-offset: 2px;
  border-radius: 0;
}

/* ---------- 4. skip link ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 120;
  padding: 10px 16px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--pitch-950);
  background: var(--bone-50);
  transform: translateY(-180%);
  transition: transform 0.18s var(--ease);
}

.skip-link:focus { transform: translateY(0); }

/* ---------- 5. 布局容器 ---------- */
.shell {
  width: min(100% - 40px, var(--shell));
  margin-inline: auto;
}

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
}

.grid-12 > * { min-width: 0; }

.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-12 { grid-column: span 12; }

@media (max-width: 900px) {
  .grid-12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }
  .span-4, .span-5, .span-6, .span-7, .span-8, .span-12 { grid-column: span 6; }
}

@media (max-width: 600px) {
  .grid-12 { grid-template-columns: minmax(0, 1fr); }
  .span-4, .span-5, .span-6, .span-7, .span-8, .span-12 { grid-column: auto; }
}

.page-offset { padding-top: calc(var(--header-h) + 32px); }

.page-hero {
  padding: clamp(36px, 6vw, 76px) 0 clamp(40px, 6vw, 76px);
  border-bottom: 1px solid var(--line);
}

.page-hero--bleed {
  margin-top: calc(var(--header-h) * -1);
  padding-top: calc(var(--header-h) + clamp(40px, 7vw, 92px));
}

.page-hero__title {
  max-width: 20em;
  font-size: clamp(30px, 5.2vw, 60px);
  color: var(--bone-50);
}

.page-hero__sub {
  max-width: 36em;
  margin-top: 6px;
  font-size: clamp(16px, 1.6vw, 18px);
  color: rgba(243, 239, 230, 0.78);
}

.section {
  padding: clamp(52px, 7vw, 104px) 0;
  border-top: 1px solid var(--line);
}

.section-head {
  display: flex;
  gap: 18px;
  align-items: flex-start;
  margin-bottom: clamp(24px, 4vw, 44px);
}

.section-head-text { min-width: 0; }

.section-index {
  flex: 0 0 auto;
  padding: 6px 0 6px 14px;
  border-left: 1px solid var(--line-strong);
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.3;
  letter-spacing: 0.08em;
  color: var(--rock-500);
  transition: color 0.3s var(--ease);
}

.is-current .section-index { color: var(--bone-50); }

.section-title {
  font-size: clamp(24px, 3vw, 34px);
  color: var(--bone-50);
}

.section-sub {
  margin-top: 8px;
  max-width: 40em;
  font-size: 15px;
  color: var(--rock-500);
}

/* ---------- 6. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 12px 20px;
  border: 1px solid var(--line-strong);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--bone-50);
  background: transparent;
  transition: border-color 0.18s var(--ease), background-color 0.18s var(--ease),
              color 0.18s var(--ease), transform 0.18s var(--ease);
}

.btn:hover {
  border-color: var(--electric-500);
  transform: translateY(-2px);
}

.btn--signal {
  border-color: rgba(255, 122, 26, 0.65);
  color: var(--amber-signal);
  background: rgba(255, 122, 26, 0.08);
}

.btn--signal:hover {
  border-color: var(--amber-signal);
  background: var(--amber-signal);
  color: var(--pitch-950);
}

.btn--ghost { border-color: var(--line); }

.btn--ghost:hover { background: rgba(52, 198, 255, 0.08); }

.btn--link {
  padding: 0 0 3px;
  border: 0;
  border-bottom: 1px solid rgba(52, 198, 255, 0.6);
  color: var(--electric-500);
}

.btn--link:hover {
  transform: none;
  border-bottom-color: var(--amber-signal);
  color: var(--amber-signal);
}

/* ---------- 7. 页头 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: transparent;
  border-bottom: 1px solid transparent;
  transition: background-color 0.28s var(--ease), border-color 0.28s var(--ease);
}

.site-header[data-scrolled] {
  background: rgba(8, 21, 15, 0.94);
  border-bottom-color: var(--line);
}

.header-shell {
  display: flex;
  align-items: center;
  gap: 16px;
  width: min(100% - 40px, var(--shell));
  height: var(--header-h);
  margin-inline: auto;
}

.brand-block {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
}

.brand-index {
  padding: 4px 7px;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--rock-500);
}

.brand {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brand-name {
  font-size: 16px;
  font-weight: 900;
  letter-spacing: -0.01em;
}

.brand-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--rock-500);
}

.site-nav {
  flex: 1 1 auto;
  min-width: 0;
  margin-left: clamp(10px, 2vw, 34px);
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
}

.nav-list::-webkit-scrollbar { display: none; }

.nav-list > li { flex: 0 0 auto; }

.nav-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 12px;
  border-bottom: 2px solid transparent;
  font-size: 14px;
  color: rgba(243, 239, 230, 0.70);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease),
              background-color 0.18s var(--ease);
}

.nav-link:hover {
  color: var(--bone-50);
  border-bottom-color: var(--electric-500);
  background-color: rgba(52, 198, 255, 0.07);
}

.nav-link[aria-current="page"] {
  color: var(--bone-50);
  border-bottom-color: var(--amber-signal);
  background-color: rgba(255, 122, 26, 0.08);
}

.nav-idx {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.04em;
  color: var(--rock-500);
}

.nav-link[aria-current="page"] .nav-idx { color: var(--amber-signal); }

.nav-label { white-space: nowrap; }

.header-utility {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-left: auto;
  flex: 0 0 auto;
}

.util-links { display: flex; gap: 14px; }

.util-link {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--rock-500);
  border-bottom: 1px solid transparent;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.util-link:hover {
  color: var(--electric-500);
  border-bottom-color: var(--electric-500);
}

.device-status {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--rock-500);
  white-space: nowrap;
}

.status-text { color: var(--rock-500); }

.status-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  background: var(--rock-500);
}

.status-dot--lime {
  background: var(--lime-state);
  box-shadow: 0 0 0 3px rgba(169, 227, 75, 0.16);
}

.status-dot--amber {
  background: var(--amber-signal);
  box-shadow: 0 0 0 3px rgba(255, 122, 26, 0.16);
}

.status-dot--electric {
  background: var(--electric-500);
  box-shadow: 0 0 0 3px rgba(52, 198, 255, 0.16);
}

.status-dot--red {
  background: var(--red-state);
  box-shadow: 0 0 0 3px rgba(255, 90, 95, 0.16);
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 9px 12px;
  border: 1px solid var(--line-strong);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  transition: border-color 0.18s var(--ease);
}

.nav-toggle:hover { border-color: var(--electric-500); }

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

.nav-toggle__bar {
  display: block;
  height: 1px;
  background: currentColor;
  transition: transform 0.2s var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:first-child {
  transform: translateY(2.5px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:last-child {
  transform: translateY(-2.5px) rotate(-45deg);
}

.nav-toggle__label { color: var(--rock-500); }

.scroll-progress {
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 100%;
  height: 2px;
  transform: scaleX(var(--progress, 0));
  transform-origin: left center;
  background: linear-gradient(90deg, var(--electric-500), var(--amber-signal));
  opacity: 0;
  transition: opacity 0.3s var(--ease);
}

.site-header[data-scrolled] .scroll-progress { opacity: 1; }

/* ---------- 8. 页脚 ---------- */
.site-footer {
  margin-top: clamp(48px, 8vw, 96px);
  background: var(--pitch-850);
  border-top: 1px solid var(--line-strong);
}

.footer-shell {
  width: min(100% - 40px, var(--shell));
  margin-inline: auto;
  padding: clamp(40px, 6vw, 72px) 0 28px;
}

.footer-top {
  display: grid;
  grid-template-columns: minmax(0, 4fr) minmax(0, 8fr);
  gap: clamp(28px, 4vw, 64px);
  padding-bottom: 34px;
  border-bottom: 1px solid var(--line);
}

.footer-mark {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--rock-500);
}

.footer-brand-name {
  margin-top: 10px;
  font-size: 20px;
  font-weight: 900;
  letter-spacing: -0.01em;
}

.footer-note {
  max-width: 32em;
  margin-top: 12px;
  font-size: 14px;
  color: rgba(243, 239, 230, 0.66);
}

.footer-contact {
  display: grid;
  gap: 8px;
  margin-top: 22px;
}

.footer-contact-row {
  display: grid;
  grid-template-columns: 76px minmax(0, 1fr);
  gap: 12px;
  padding-top: 8px;
  border-top: 1px solid var(--line);
}

.footer-contact-key {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--rock-500);
}

.footer-contact-value {
  font-family: var(--font-mono);
  font-size: 12px;
  color: rgba(243, 239, 230, 0.86);
  word-break: break-word;
}

.footer-columns {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 24px;
}

.footer-col-title {
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.10em;
  color: var(--rock-500);
}

.footer-list {
  display: grid;
  gap: 8px;
  margin-top: 12px;
}

.footer-link {
  font-size: 14px;
  color: rgba(243, 239, 230, 0.76);
  border-bottom: 1px solid transparent;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.footer-link:hover {
  color: var(--electric-500);
  border-bottom-color: var(--electric-500);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 24px;
  padding-top: 20px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--rock-500);
}

.footer-legal { color: var(--rock-500); }

.footer-meta { color: rgba(138, 143, 136, 0.8); }

.footer-back {
  padding-bottom: 2px;
  color: var(--amber-signal);
  border-bottom: 1px solid rgba(255, 122, 26, 0.5);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.footer-back:hover {
  color: var(--bone-50);
  border-bottom-color: var(--bone-50);
}

/* ---------- 9. 面包屑 ---------- */
.crumbs {
  padding: 20px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--rock-500);
}

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

.crumb-item + .crumb-item::before {
  content: "/";
  margin-right: 8px;
  color: rgba(138, 143, 136, 0.5);
}

.crumb-link:hover { color: var(--electric-500); }

.crumb-item[aria-current="page"] { color: var(--bone-50); }

/* ---------- 10. 数据面板 / 状态 ---------- */
.data-panel {
  border: 1px solid var(--line-strong);
  background: rgba(15, 36, 26, 0.72);
}

.data-panel__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 18px;
  border-bottom: 1px solid var(--line);
}

.data-panel__title {
  font-size: 15px;
  font-weight: 700;
}

.data-panel__stamp {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--rock-500);
}

.data-panel__stamp.is-pulse { animation: stamp-pulse 220ms var(--ease) 1; }

@keyframes stamp-pulse {
  0% { opacity: 1; }
  40% { opacity: 0.35; }
  100% { opacity: 1; }
}

.data-panel__body { padding: 20px 18px; }

.data-panel__legend {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  padding: 14px 18px;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--rock-500);
}

.data-panel__source {
  padding: 0 18px 16px;
  font-size: 13px;
  color: var(--rock-500);
}

.kpi { display: flex; flex-direction: column; gap: 6px; }

.kpi__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(30px, 5vw, 56px);
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--bone-50);
}

.kpi__label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--rock-500);
}

/* ---------- 11. 目录清单 / 折叠 ---------- */
.index-list { border-top: 1px solid var(--line); }

.index-item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  gap: 16px;
  align-items: baseline;
  padding: 16px 6px;
  border-bottom: 1px solid var(--line);
  transition: background-color 0.18s var(--ease), transform 0.18s var(--ease);
}

.index-item:hover {
  background-color: rgba(52, 198, 255, 0.06);
  transform: translateX(2px);
}

.index-num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--rock-500);
}

.index-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--bone-50);
}

.index-desc {
  font-size: 14px;
  color: var(--rock-500);
}

.index-arrow {
  font-family: var(--font-mono);
  color: var(--rock-500);
  transition: color 0.18s var(--ease);
}

.index-item:hover .index-arrow { color: var(--electric-500); }

.toc-list {
  display: grid;
  gap: 2px;
  border-top: 1px solid var(--line);
}

.toc-link {
  display: flex;
  gap: 12px;
  align-items: baseline;
  padding: 10px 12px;
  border-left: 2px solid transparent;
  font-size: 14px;
  color: rgba(243, 239, 230, 0.70);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease),
              background-color 0.18s var(--ease);
}

.toc-link:hover {
  color: var(--bone-50);
  border-left-color: var(--electric-500);
  background-color: rgba(52, 198, 255, 0.06);
}

.toc-link[aria-current] {
  color: var(--bone-50);
  border-left-color: var(--amber-signal);
}

.fold {
  border: 1px solid var(--line);
  background: rgba(15, 36, 26, 0.5);
}

.fold + .fold { margin-top: -1px; }

.fold__summary {
  display: flex;
  gap: 14px;
  align-items: baseline;
  padding: 16px 18px;
  font-weight: 500;
  cursor: pointer;
  list-style: none;
  transition: background-color 0.18s var(--ease);
}

.fold__summary::-webkit-details-marker { display: none; }

.fold__summary:hover { background-color: rgba(52, 198, 255, 0.06); }

.fold__summary::after {
  content: "+";
  margin-left: auto;
  font-family: var(--font-mono);
  color: var(--electric-500);
}

.fold[open] .fold__summary::after { content: "–"; }

.fold[open] .fold__summary { border-bottom: 1px solid var(--line); }

.fold__mark {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--rock-500);
}

.fold__body {
  padding: 18px;
  font-size: 15px;
  color: rgba(243, 239, 230, 0.82);
}

/* ---------- 12. 标签 / 框景 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 8px;
  border: 1px solid var(--line-strong);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--rock-500);
}

.tag--clay { border-color: rgba(182, 114, 76, 0.6); color: var(--clay-500); }
.tag--electric { border-color: rgba(52, 198, 255, 0.5); color: var(--electric-500); }
.tag--amber { border-color: rgba(255, 122, 26, 0.5); color: var(--amber-signal); }
.tag--lime { border-color: rgba(169, 227, 75, 0.5); color: var(--lime-state); }

.frame {
  position: relative;
  padding: clamp(20px, 3vw, 40px);
  border: 1px solid var(--line-strong);
  background: linear-gradient(180deg, rgba(15, 36, 26, 0.85), rgba(8, 21, 15, 0.65));
}

.frame::before,
.frame::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 8px;
  background-image: repeating-linear-gradient(to right, var(--line-strong) 0 1px, transparent 1px 26px);
}

.frame::before { top: -1px; }
.frame::after { bottom: -1px; }

.frame__label {
  position: absolute;
  top: -12px;
  left: 24px;
  padding: 0 8px;
  background: var(--pitch-950);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--rock-500);
}

/* ---------- 13. 图片容器（页面阶段使用） ---------- */
.media {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  background: linear-gradient(160deg, var(--pitch-850), var(--pitch-950));
}

.media::before {
  content: "";
  display: block;
  padding-top: var(--media-ratio, 62.5%);
}

.media img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.92) contrast(1.04);
}

.media__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 10px 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--bone-50);
  background: linear-gradient(to top, rgba(8, 21, 15, 0.92), rgba(8, 21, 15, 0));
}

.media--hero { --media-ratio: 62.5%; }
.media--wide { --media-ratio: 40%; }
.media--square { --media-ratio: 100%; }
.media--portrait { --media-ratio: 133%; }

.media--placeholder::after {
  content: attr(data-placeholder);
  position: absolute;
  inset: 8px;
  display: grid;
  place-items: center;
  padding: 12px;
  text-align: center;
  border: 1px dashed var(--line-strong);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--rock-500);
}

/* ---------- 14. 显现与章节状态 ---------- */
.has-js [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.5s var(--ease), transform 0.5s var(--ease);
}

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

/* ---------- 15. 响应式 ---------- */
@media (max-width: 1200px) {
  .util-links { display: none; }
}

@media (max-width: 1024px) {
  .btn--signal { padding: 10px 14px; font-size: 13px; }
}

@media (max-width: 960px) {
  :root { --header-h: 64px; }

  .brand-tag { display: none; }
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: fixed;
    left: 0;
    right: 0;
    top: var(--header-h);
    display: none;
    max-height: calc(100vh - var(--header-h));
    margin-left: 0;
    padding: 10px 20px 22px;
    overflow-y: auto;
    background: var(--pitch-800);
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
  }

  .site-nav[data-open] { display: block; }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    overflow: visible;
  }

  .nav-link {
    width: 100%;
    padding: 14px 6px;
    border-bottom: 1px solid var(--line);
    border-left: 2px solid transparent;
    font-size: 15px;
  }

  .nav-link:hover {
    border-bottom-color: var(--line);
    border-left-color: var(--electric-500);
  }

  .nav-link[aria-current="page"] {
    border-bottom-color: var(--line);
    border-left-color: var(--amber-signal);
  }

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

@media (max-width: 900px) {
  .device-status { display: none; }
}

@media (max-width: 720px) {
  .footer-columns { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
  .footer-contact-row { grid-template-columns: minmax(0, 1fr); gap: 4px; }
}

@media (max-width: 560px) {
  .btn--signal { display: none; }
  .brand-index { display: none; }
  .footer-columns { grid-template-columns: minmax(0, 1fr); }
  .index-item { grid-template-columns: auto minmax(0, 1fr); }
  .index-arrow { display: none; }
}

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

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

  .data-panel__stamp.is-pulse { animation: none; }

  .btn:hover { transform: none; }
  .index-item:hover { transform: none; }
}