/* ============================================================
   非凡体育 · 共享站点样式 /assets/site.css
   控制台基底 / 悬浮胶囊导航 / 双侧栏内容网格 / 档案式组件
   ============================================================ */

*,
*::before,
*::after { box-sizing: border-box; }

:root {
  /* 色彩体系 */
  --ink-900: #081426;
  --ink-800: #0F2038;
  --ink-700: #132A47;
  --line: #27405F;
  --cyan: #35F2E4;
  --orange: #FF7A2F;
  --grass: #58D68D;
  --brick: #C8543F;
  --mist: #E9F3F7;
  --steel: #8FA6BD;
  --white: #FFFFFF;

  /* 尺寸与节奏 */
  --shell-max: 1280px;
  --gutter: clamp(16px, 4vw, 32px);
  --radius-s: 8px;
  --radius-m: 14px;
  --radius-pill: 999px;
  --header-offset: 96px;

  /* 字体 */
  --sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;

  /* 动效 */
  --ease: cubic-bezier(.22, .61, .36, 1);
  --dur: 180ms;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-offset);
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--mist);
  background-color: var(--ink-900);
  background-image:
    radial-gradient(900px 460px at 10% -8%, rgba(53, 242, 228, .10), transparent 62%),
    radial-gradient(820px 440px at 94% -4%, rgba(255, 122, 47, .09), transparent 64%),
    repeating-linear-gradient(180deg, rgba(39, 64, 95, .16) 0 1px, transparent 1px 96px),
    linear-gradient(180deg, #081426 0%, #081426 58%, #06101F 100%);
  background-repeat: no-repeat;
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.75;
  font-weight: 400;
  letter-spacing: .01em;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  margin: 0 0 .5em;
  color: var(--white);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -.015em;
}

h1 { font-size: clamp(34px, 6vw, 64px); }

p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }

a { color: var(--cyan); text-decoration: none; text-underline-offset: 3px; }

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

ul, ol { margin: 0; padding: 0; }

button { font: inherit; color: inherit; }

hr { border: 0; }

[hidden] { display: none !important; }

/* ---------- 焦点可见 ---------- */
:where(a, button, summary, input, textarea, select, [tabindex]):focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: 3px;
  box-shadow: inset 0 0 0 1px var(--mist);
  border-radius: var(--radius-s);
}

/* ---------- 工具类 ---------- */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 200;
  transform: translateY(-180%);
  padding: 10px 18px;
  border-radius: var(--radius-s);
  background: var(--orange);
  color: #0B1220;
  font-weight: 800;
  font-size: 14px;
  letter-spacing: .04em;
  box-shadow: 0 18px 36px -20px #000;
  transition: transform var(--dur) var(--ease);
}

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

.container {
  width: 100%;
  max-width: var(--shell-max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.site-main { display: block; padding-block: clamp(18px, 3.5vw, 36px); }

.section { padding-block: clamp(26px, 4.5vw, 52px); }

.section-head {
  display: grid;
  gap: 10px;
  margin-bottom: clamp(18px, 3vw, 28px);
}

.section-title {
  margin: 0;
  font-size: clamp(24px, 3.4vw, 34px);
  line-height: 1.22;
  color: var(--white);
}

.index-label {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.index-label::before {
  content: "";
  width: 20px;
  height: 1px;
  background: linear-gradient(90deg, var(--cyan), transparent);
}

.content-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(20px, 3vw, 34px);
  align-items: start;
}

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

.rail {
  position: relative;
  display: grid;
  gap: 14px;
  min-width: 0;
}

@media (min-width: 1100px) {
  .content-grid {
    grid-template-columns: 200px minmax(0, 1fr) 260px;
  }
  .rail {
    position: sticky;
    top: calc(var(--header-offset) + 8px);
  }
}

.prose { max-width: 68ch; }
.prose p { margin-bottom: 1em; }
.prose h2 { margin-top: 1.6em; font-size: clamp(22px, 2.6vw, 28px); }
.prose ul, .prose ol { margin: 0 0 1em; padding-left: 1.25em; }
.prose li { margin-bottom: .4em; }

.divider {
  height: 1px;
  border: 0;
  margin: clamp(24px, 4vw, 40px) 0;
  background: linear-gradient(90deg, var(--line), rgba(39, 64, 95, .1));
}

.note {
  margin: 0;
  padding: 4px 0 4px 14px;
  border-left: 2px solid rgba(53, 242, 228, .55);
  font-size: 13px;
  line-height: 1.75;
  color: var(--steel);
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background: rgba(15, 32, 56, .85);
  color: var(--mist);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .06em;
  text-decoration: none;
  cursor: pointer;
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease),
              box-shadow var(--dur) var(--ease), background-color var(--dur) var(--ease),
              color var(--dur) var(--ease);
}

.btn:hover {
  transform: translateY(-2px);
  border-color: var(--cyan);
  color: var(--white);
  box-shadow: 0 18px 34px -26px var(--cyan);
}

.btn--primary {
  background: linear-gradient(135deg, var(--orange), #FF9757);
  border-color: rgba(255, 255, 255, .18);
  color: #0C1424;
  box-shadow: 0 18px 34px -22px rgba(255, 122, 47, .85);
}

.btn--primary:hover {
  color: #0C1424;
  border-color: rgba(255, 255, 255, .4);
  box-shadow: 0 22px 40px -22px rgba(255, 122, 47, .95);
}

.btn--ghost {
  background: transparent;
  border-color: rgba(53, 242, 228, .5);
  color: var(--cyan);
}

.btn--quiet {
  padding-inline: 10px;
  background: transparent;
  border-color: transparent;
  color: var(--steel);
}

.btn--quiet:hover {
  transform: none;
  box-shadow: none;
  background: transparent;
  color: var(--cyan);
}

/* ---------- 面包屑 ---------- */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0 0 clamp(16px, 3vw, 26px);
  padding: 0;
  list-style: none;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--steel);
}

.breadcrumbs__item {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.breadcrumbs__link { color: var(--steel); }
.breadcrumbs__link:hover { color: var(--cyan); }
.breadcrumbs__sep { color: rgba(143, 166, 189, .5); }
.breadcrumbs__current { color: var(--mist); }

/* ---------- 面板与卡片 ---------- */
.panel {
  position: relative;
  padding: clamp(16px, 2.4vw, 24px);
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: linear-gradient(180deg, rgba(15, 32, 56, .92), rgba(9, 22, 40, .92));
  box-shadow: 0 26px 50px -42px #000, inset 0 1px 0 rgba(233, 243, 247, .05);
}

.panel--data { padding: 14px; }

.panel__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.panel__title {
  margin: 0;
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--steel);
}

.card {
  position: relative;
  display: grid;
  gap: 8px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: rgba(15, 32, 56, .72);
  overflow: hidden;
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease),
              box-shadow var(--dur) var(--ease);
}

.card::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: linear-gradient(105deg, transparent 32%, rgba(53, 242, 228, .14) 50%, transparent 68%);
  opacity: 0;
  pointer-events: none;
  transition: opacity 220ms var(--ease);
}

.card:hover {
  transform: translateY(-2px);
  border-color: rgba(53, 242, 228, .6);
  box-shadow: 0 24px 44px -36px var(--cyan);
}

.card:hover::after { opacity: 1; }

.card__label {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--cyan);
}

.card__title {
  margin: 0;
  font-size: 18px;
  font-weight: 800;
  line-height: 1.35;
  color: var(--white);
}

.card__meta {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--steel);
}

.grid-cards {
  display: grid;
  gap: 14px;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

/* ---------- 标签 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background: rgba(8, 20, 38, .7);
  font-family: var(--mono);
  font-size: 10.5px;
  font-weight: 600;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--steel);
}

.tag--cyan { color: var(--cyan); border-color: rgba(53, 242, 228, .45); background: rgba(53, 242, 228, .1); }
.tag--orange { color: var(--orange); border-color: rgba(255, 122, 47, .45); background: rgba(255, 122, 47, .1); }
.tag--grass { color: var(--grass); border-color: rgba(88, 214, 141, .45); background: rgba(88, 214, 141, .1); }
.tag--brick { color: #E2795F; border-color: rgba(200, 84, 63, .55); background: rgba(200, 84, 63, .14); }

/* ---------- 数据条 ---------- */
.data-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(118px, 1fr));
  gap: 1px;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: var(--line);
  overflow: hidden;
}

.data-strip__item {
  display: grid;
  gap: 2px;
  padding: 12px 14px;
  background: rgba(9, 22, 40, .94);
}

.data-strip__value {
  font-family: var(--mono);
  font-size: clamp(20px, 2.6vw, 26px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -.02em;
  color: var(--white);
}

.data-strip__label {
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--steel);
}

.data-strip__item--accent .data-strip__value { color: var(--cyan); }

/* ---------- 图片容器 ---------- */
.media {
  position: relative;
  aspect-ratio: 16 / 9;
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  background: linear-gradient(140deg, var(--ink-800), var(--ink-900));
  overflow: hidden;
}

.media--wide { aspect-ratio: 21 / 9; }
.media--tall { aspect-ratio: 3 / 4; }

.media img,
.media__img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(53, 242, 228, .12), transparent 46%, rgba(255, 122, 47, .1));
  mix-blend-mode: screen;
  pointer-events: none;
}

.media--empty::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(39, 64, 95, .55) 1px, transparent 1px),
    linear-gradient(90deg, rgba(39, 64, 95, .55) 1px, transparent 1px);
  background-size: 44px 44px;
  opacity: .5;
}

.media__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 1;
  padding: 10px 14px;
  background: linear-gradient(180deg, transparent, rgba(6, 16, 31, .94));
  font-family: var(--mono);
  font-size: 10.5px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--mist);
}

/* ---------- 锚点导航 ---------- */
.toc {
  display: grid;
  gap: 6px;
  padding-left: 12px;
  border-left: 1px solid var(--line);
}

.toc__link {
  padding: 3px 0;
  font-size: 13px;
  line-height: 1.55;
  color: var(--steel);
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease);
}

.toc__link:hover,
.toc__link[aria-current="true"] { color: var(--cyan); }

/* ============================================================
   头部 · 悬浮胶囊浮岛
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  padding: 14px clamp(10px, 2.4vw, 26px) 0;
  pointer-events: none;
}

.header-shell {
  pointer-events: auto;
  position: relative;
  display: flex;
  align-items: center;
  gap: 16px;
  max-width: var(--shell-max);
  margin-inline: auto;
  padding: 10px 12px 10px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background: linear-gradient(180deg, rgba(15, 32, 56, .94), rgba(8, 20, 38, .9));
  box-shadow: 0 24px 48px -34px rgba(0, 0, 0, .95), inset 0 1px 0 rgba(233, 243, 247, .06);
  -webkit-backdrop-filter: blur(16px);
  backdrop-filter: blur(16px);
  transition: border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.header-shell::before {
  content: "";
  position: absolute;
  inset: 0 0 auto;
  height: 1px;
  border-radius: inherit;
  background: linear-gradient(90deg, transparent, rgba(53, 242, 228, .55), rgba(255, 122, 47, .4), transparent);
  opacity: .8;
}

.site-header[data-open] .header-shell {
  border-color: rgba(53, 242, 228, .45);
  box-shadow: 0 30px 56px -32px rgba(0, 0, 0, .95), 0 0 0 1px rgba(53, 242, 228, .18);
}

/* 品牌轨道 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  color: var(--mist);
  text-decoration: none;
}

.brand__mark {
  position: relative;
  display: grid;
  place-items: center;
  flex: 0 0 auto;
  width: 32px;
  height: 32px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: radial-gradient(circle at 30% 24%, rgba(53, 242, 228, .5), rgba(15, 32, 56, .95) 72%);
}

.brand__mark-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 12px rgba(53, 242, 228, .9);
}

.brand__mark-line {
  position: absolute;
  left: 6px;
  right: 6px;
  bottom: 7px;
  height: 1px;
  background: linear-gradient(90deg, var(--orange), transparent);
}

.brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
  min-width: 0;
}

.brand__name {
  font-size: 16px;
  font-weight: 800;
  letter-spacing: .08em;
  color: var(--white);
  transition: color var(--dur) var(--ease);
}

.brand:hover .brand__name { color: var(--cyan); }

.brand__tag {
  font-family: var(--mono);
  font-size: 9.5px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--steel);
  white-space: nowrap;
}

.brand__edition {
  margin-left: 4px;
  padding: 2px 8px;
  border: 1px solid rgba(255, 122, 47, .45);
  border-radius: var(--radius-pill);
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: .12em;
  color: var(--orange);
  white-space: nowrap;
}

/* 移动按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  margin-left: auto;
  padding: 9px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius-pill);
  background: rgba(8, 20, 38, .7);
  color: var(--mist);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .16em;
  cursor: pointer;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.nav-toggle:hover { border-color: rgba(53, 242, 228, .6); color: var(--cyan); }

.nav-toggle__bars {
  display: inline-flex;
  flex-direction: column;
  gap: 4px;
  width: 16px;
}

.nav-toggle__bars span {
  display: block;
  height: 1.5px;
  border-radius: 2px;
  background: currentColor;
  transition: transform var(--dur) var(--ease), opacity var(--dur) var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:first-child {
  transform: translateY(2.75px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:last-child {
  transform: translateY(-2.75px) rotate(-45deg);
}

.nav-toggle__label { line-height: 1; }

/* 导航胶囊 */
.primary-nav {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-left: auto;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 9px 13px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  color: var(--steel);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .04em;
  white-space: nowrap;
  text-decoration: none;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease),
              background-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.nav-link:hover {
  transform: translateY(-1px);
  border-color: rgba(53, 242, 228, .4);
  background-color: rgba(53, 242, 228, .08);
  color: var(--white);
}

.nav-link[aria-current="page"] {
  border-color: rgba(53, 242, 228, .45);
  background-color: rgba(53, 242, 228, .12);
  color: var(--cyan);
}

.nav-link[aria-current="page"]::after {
  content: "";
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 8px var(--cyan);
}

.nav-cta {
  margin-left: 6px;
  padding: 10px 18px;
  border: 1px solid rgba(255, 255, 255, .14);
  border-radius: var(--radius-pill);
  background: linear-gradient(135deg, var(--orange), #FF9757);
  color: #0C1424;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: .08em;
  white-space: nowrap;
  text-decoration: none;
  box-shadow: 0 14px 28px -20px rgba(255, 122, 47, .95);
  transition: transform var(--dur) var(--ease), filter var(--dur) var(--ease);
}

.nav-cta:hover { transform: translateY(-1px); filter: brightness(1.07); color: #0C1424; }

/* 阅读进度细线 */
.header-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  z-index: 90;
  background: rgba(39, 64, 95, .35);
  pointer-events: none;
}

.header-progress__bar {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--cyan), var(--orange));
  transition: width 120ms linear;
}

/* ============================================================
   页脚 · 控制台下缘
   ============================================================ */
.site-footer {
  position: relative;
  margin-top: clamp(48px, 8vw, 96px);
  border-top: 1px solid var(--line);
  background:
    radial-gradient(760px 320px at 8% 0%, rgba(53, 242, 228, .08), transparent 66%),
    linear-gradient(180deg, rgba(15, 32, 56, .92), rgba(6, 16, 31, .99));
  color: var(--mist);
}

.footer-shell {
  display: grid;
  grid-template-columns: 1.4fr .8fr 1fr 1fr;
  gap: clamp(22px, 4vw, 48px);
  max-width: var(--shell-max);
  margin-inline: auto;
  padding: clamp(34px, 5.5vw, 62px) var(--gutter) clamp(26px, 4vw, 40px);
}

.footer-brand,
.footer-nav,
.footer-contact,
.footer-legal { min-width: 0; }

.footer-brand__link {
  display: inline-block;
  font-size: 22px;
  font-weight: 800;
  letter-spacing: .1em;
  color: var(--white);
  transition: color var(--dur) var(--ease);
}

.footer-brand__link:hover { color: var(--cyan); }

.footer-brand__line {
  margin: 12px 0 0;
  max-width: 30ch;
  font-size: 14px;
  line-height: 1.7;
  color: var(--steel);
}

.footer-brand__meta {
  margin: 14px 0 0;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--cyan);
}

.footer-title {
  margin: 0 0 14px;
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--steel);
}

.footer-list {
  display: grid;
  gap: 9px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.footer-link {
  display: inline-block;
  font-size: 14px;
  line-height: 1.5;
  color: var(--mist);
  border-bottom: 1px solid transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.footer-link:hover {
  color: var(--cyan);
  border-bottom-color: rgba(53, 242, 228, .6);
}

.footer-link[aria-current="page"] {
  color: var(--cyan);
  border-bottom-color: rgba(53, 242, 228, .35);
}

.footer-contact__label {
  display: block;
  margin-bottom: 2px;
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--steel);
}

.footer-contact__value {
  display: block;
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.6;
  letter-spacing: .02em;
  color: var(--mist);
  word-break: break-word;
}

.footer-contact__note {
  margin: 14px 0 0;
  max-width: 34ch;
  font-size: 12px;
  line-height: 1.75;
  color: var(--steel);
}

.footer-legal {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.footer-legal__list { gap: 9px; }

.footer-base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 24px;
  max-width: var(--shell-max);
  margin-inline: auto;
  padding: 16px var(--gutter) 26px;
  border-top: 1px solid var(--line);
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--steel);
}

.footer-copy,
.footer-icp,
.footer-note { margin: 0; }

.footer-icp { color: var(--mist); }
.footer-note { opacity: .85; }

/* 回到顶部 */
.back-to-top {
  position: fixed;
  right: clamp(12px, 3vw, 26px);
  bottom: clamp(12px, 3vw, 26px);
  z-index: 95;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  border: 1px solid rgba(53, 242, 228, .45);
  border-radius: var(--radius-pill);
  background: rgba(8, 20, 38, .92);
  color: var(--cyan);
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .14em;
  cursor: pointer;
  box-shadow: 0 20px 40px -28px #000;
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.back-to-top:hover { transform: translateY(-2px); border-color: var(--cyan); }
.back-to-top[hidden] { display: none; }

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 1024px) {
  .footer-shell { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 940px) {
  .site-header { padding: 10px clamp(10px, 3vw, 18px) 0; }

  .header-shell {
    flex-wrap: wrap;
    gap: 10px;
    padding: 10px 12px;
    border-radius: 20px;
  }

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

  .primary-nav {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 6px;
    width: 100%;
    margin: 8px 0 2px;
    padding: 12px 0 4px;
    border-top: 1px solid var(--line);
  }

  .primary-nav[data-open] { display: flex; }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
  }

  .nav-link {
    justify-content: space-between;
    padding: 12px 14px;
    border-radius: 12px;
    font-size: 15px;
  }

  .nav-link[aria-current="page"]::after { order: 2; }

  .nav-cta {
    margin: 4px 0 0;
    padding: 13px 18px;
    border-radius: 12px;
    text-align: center;
    font-size: 14px;
  }
}

@media (max-width: 620px) {
  body { font-size: 16px; }

  .footer-shell {
    grid-template-columns: 1fr;
    gap: 26px;
  }

  .footer-base {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

  .brand__tag { display: none; }
}

@media (max-width: 460px) {
  .brand__edition { display: none; }
  .brand__name { font-size: 15px; }
  .nav-toggle { padding: 8px 12px; }
  .back-to-top { padding: 9px 14px; font-size: 10px; }
}

/* ---------- 减少动态 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }

  .card:hover,
  .btn:hover,
  .nav-link:hover,
  .nav-cta:hover,
  .back-to-top:hover { transform: none; }

  .card::after { display: none; }

  .header-progress__bar { transition: none; }
}