/* ============================================================
   奇异果体育 · /assets/site.css
   共享外壳 + 通用组件（页面特色布局由页面专属 CSS 承担）
   ============================================================ */

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

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

body,
h1, h2, h3, h4, h5, h6,
p, figure, blockquote, dl, dd,
ul, ol {
  margin: 0;
}

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

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

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  padding: 0;
}

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

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

@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;
  }
}

/* ---------- 2. Tokens ---------- */
:root {
  /* 品牌色 */
  --kiwi: #C8FF3D;
  --kiwi-soft: #E6FFA8;
  --ink: #1B1512;
  --ink-soft: #3D3833;
  --ember: #E8482A;
  --paper: #F3EFE7;
  --card: #FCF9F2;
  --moss: #2F3A22;
  --gold: #C9A45C;
  --teal: #2E8B7E;

  /* 线条 */
  --line: rgba(27, 21, 18, 0.16);
  --line-strong: rgba(27, 21, 18, 0.42);
  --line-light: rgba(252, 249, 242, 0.18);

  /* 字体 */
  --f-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", Georgia, "Times New Roman", serif;
  --f-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", system-ui, -apple-system, "Segoe UI", sans-serif;
  --f-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Courier New", monospace;
  --f-narrow: "Helvetica Neue Condensed", "Arial Narrow", "Roboto Condensed", "PingFang SC", "Microsoft YaHei", sans-serif;

  /* 度量 */
  --gutter: clamp(18px, 4vw, 42px);
  --header-h: 76px;
  --radius: 2px;
  --shadow-print: 5px 5px 0 rgba(27, 21, 18, 0.92);
  --shadow-soft: 0 20px 44px -30px rgba(27, 21, 18, 0.75);
}

/* ---------- 3. 基础排版 ---------- */
body {
  font-family: var(--f-sans);
  font-size: clamp(16px, 0.4vw + 15px, 18px);
  line-height: 1.78;
  letter-spacing: 0.012em;
  color: var(--ink-soft);
  background-color: var(--paper);
  background-image: linear-gradient(90deg, rgba(27, 21, 18, 0.038) 1px, transparent 1px);
  background-size: 104px 100%;
  background-repeat: repeat;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: var(--f-serif);
  color: var(--ink);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.012em;
  text-wrap: balance;
}

h1 { font-size: clamp(2.2rem, 5.4vw, 4rem); line-height: 1.08; }
h2 { font-size: clamp(1.55rem, 2.9vw, 2.4rem); }
h3 { font-size: clamp(1.12rem, 1.7vw, 1.5rem); line-height: 1.38; }
h4 { font-size: clamp(1rem, 1.2vw, 1.15rem); line-height: 1.45; }

strong { color: var(--ink); font-weight: 700; }

small { font-size: 0.82em; }

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

/* ---------- 4. 可访问性 ---------- */
:focus-visible {
  outline: 3px solid var(--ember);
  outline-offset: 3px;
}

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

.skip-link {
  position: fixed;
  top: -80px;
  left: 14px;
  z-index: 220;
  display: inline-block;
  padding: 0.7em 1.15em;
  font-family: var(--f-narrow);
  font-weight: 800;
  font-size: 0.95rem;
  letter-spacing: 0.05em;
  color: var(--ink);
  background: var(--kiwi);
  border: 2px solid var(--ink);
  box-shadow: var(--shadow-print);
  transition: top 0.18s ease;
}

.skip-link:focus {
  top: 14px;
}

/* ---------- 5. 容器与区块 ---------- */
.wrap {
  width: min(1200px, 100% - var(--gutter) * 2);
  margin-inline: auto;
}

.wrap--narrow {
  width: min(760px, 100% - var(--gutter) * 2);
  margin-inline: auto;
}

.section {
  padding-block: clamp(40px, 6vw, 88px);
}

.rule {
  height: 1px;
  border: 0;
  margin: 0;
  background: var(--line);
}

/* ---------- 6. 工具类 ---------- */
.u-mono {
  font-family: var(--f-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
}

.u-narrow {
  font-family: var(--f-narrow);
  font-stretch: condensed;
  font-weight: 800;
  letter-spacing: 0.04em;
}

.u-serif { font-family: var(--f-serif); }

.hl {
  background: var(--kiwi);
  color: var(--ink);
  padding: 0.04em 0.3em;
  border-radius: 1px;
  box-decoration-break: clone;
  -webkit-box-decoration-break: clone;
  font-weight: 600;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.55em;
  font-family: var(--f-mono);
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink);
}

.eyebrow::before {
  content: "";
  width: 9px;
  height: 9px;
  background: var(--kiwi);
  border: 1px solid var(--ink);
  flex: none;
}

/* ---------- 7. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5em;
  padding: 0.78em 1.45em;
  font-family: var(--f-narrow);
  font-stretch: condensed;
  font-weight: 800;
  font-size: 0.95rem;
  letter-spacing: 0.06em;
  line-height: 1.2;
  border: 1px solid var(--ink);
  border-radius: var(--radius);
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, background-color 0.18s ease, color 0.18s ease;
}

.btn--kiwi {
  background: var(--kiwi);
  color: var(--ink);
  border-color: var(--ink);
  box-shadow: 4px 4px 0 var(--ink);
}

.btn--kiwi:hover,
.btn--kiwi:focus-visible {
  background: var(--kiwi-soft);
  transform: translate(-1px, -1px);
  box-shadow: 6px 6px 0 var(--ink);
}

.btn--ink {
  background: var(--ink);
  color: var(--card);
  border-color: var(--ink);
  box-shadow: 4px 4px 0 rgba(200, 255, 61, 0.9);
}

.btn--ink:hover,
.btn--ink:focus-visible {
  background: var(--moss);
  transform: translate(-1px, -1px);
  box-shadow: 6px 6px 0 rgba(200, 255, 61, 0.9);
}

.btn--ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--line-strong);
}

.btn--ghost:hover,
.btn--ghost:focus-visible {
  background: var(--kiwi-soft);
  border-color: var(--ink);
}

.btn--block {
  display: flex;
  width: 100%;
}

/* ---------- 8. 标签 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.4em;
  padding: 0.24em 0.62em;
  font-family: var(--f-mono);
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink);
  background: var(--card);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  white-space: nowrap;
}

.tag--kiwi { background: var(--kiwi); border-color: var(--ink); }
.tag--ember { background: var(--ember); border-color: var(--ember); color: var(--card); }
.tag--gold { background: var(--gold); border-color: var(--gold); color: var(--ink); }
.tag--teal { background: var(--teal); border-color: var(--teal); color: var(--card); }

/* ---------- 9. 卡片 / 网格 ---------- */
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(16px, 2vw, 26px);
  box-shadow: 0 1px 0 var(--line);
}

.grid {
  display: grid;
  gap: clamp(16px, 2.4vw, 32px);
}

.grid--2 { grid-template-columns: repeat(auto-fit, minmax(min(290px, 100%), 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(min(240px, 100%), 1fr)); }

/* ---------- 10. 面包屑 ---------- */
.crumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5em;
  font-family: var(--f-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: var(--ink-soft);
}

.crumbs a {
  border-bottom: 1px solid var(--line-strong);
}

.crumbs a:hover {
  border-bottom-color: var(--ink);
  color: var(--ink);
}

.crumbs__sep {
  color: var(--ink);
  opacity: 0.4;
}

.crumbs [aria-current="page"] {
  color: var(--ink);
  font-weight: 600;
}

/* ---------- 11. 正文容器 ---------- */
.prose {
  max-width: 70ch;
}

.prose > p,
.prose > ul,
.prose > ol,
.prose > dl {
  margin-bottom: 1.05em;
}

.prose h2 { margin-block: 1.9em 0.6em; }
.prose h3 { margin-block: 1.5em 0.5em; }

.prose a {
  color: var(--ink);
  border-bottom: 2px solid var(--kiwi);
}

.prose a:hover {
  background: var(--kiwi-soft);
}

.prose ul li,
.prose ol li {
  position: relative;
  padding-left: 1.3em;
  margin-bottom: 0.5em;
}

.prose ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 7px;
  height: 7px;
  background: var(--kiwi);
  border: 1px solid var(--ink);
}

.prose ol {
  counter-reset: prose-ol;
}

.prose ol li::before {
  counter-increment: prose-ol;
  content: counter(prose-ol, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 0;
  font-family: var(--f-mono);
  font-size: 0.78em;
  color: var(--ink);
}

.prose blockquote {
  margin-block: 1.6em;
  padding-left: 1.1em;
  border-left: 4px solid var(--kiwi);
  font-family: var(--f-serif);
  font-size: 1.08em;
  color: var(--ink);
}

.prose code {
  font-family: var(--f-mono);
  font-size: 0.9em;
  background: rgba(200, 255, 61, 0.38);
  padding: 0.1em 0.4em;
  border-radius: 1px;
}

/* ---------- 12. 图片容器基础 ---------- */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  background: var(--moss);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

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

.media--wide { aspect-ratio: 16 / 9; }
.media--photo { aspect-ratio: 4 / 3; }
.media--portrait { aspect-ratio: 4 / 5; }
.media--square { aspect-ratio: 1 / 1; }
.media--free { aspect-ratio: auto; }

.media__badge {
  position: absolute;
  top: 10px;
  left: 10px;
  z-index: 2;
  padding: 0.24em 0.6em;
  font-family: var(--f-mono);
  font-size: 0.66rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink);
  background: var(--kiwi);
  border: 1px solid var(--ink);
  border-radius: var(--radius);
}

.media__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
  padding: 1.6rem 0.95rem 0.8rem;
  font-family: var(--f-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--card);
  background: linear-gradient(180deg, rgba(27, 21, 18, 0) 0%, rgba(27, 21, 18, 0.86) 100%);
}

/* ============================================================
   13. 站点头部
   ============================================================ */
.site-header {
  --hd-fg: var(--ink);
  --hd-bg: transparent;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 50;
  color: var(--hd-fg);
  background-color: var(--hd-bg);
  transition: background-color 0.35s ease, color 0.3s ease, box-shadow 0.35s ease;
}

.site-header::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background: linear-gradient(180deg, rgba(243, 239, 231, 0.94) 0%, rgba(243, 239, 231, 0.6) 58%, rgba(243, 239, 231, 0) 100%);
  transition: opacity 0.35s ease;
}

.site-header::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 1px;
  background: var(--line);
  transition: background-color 0.35s ease;
}

.site-header[data-scrolled] {
  --hd-fg: var(--card);
  --hd-bg: var(--ink);
  box-shadow: 0 16px 34px -26px rgba(0, 0, 0, 0.9);
}

.site-header[data-scrolled]::before { opacity: 0; }

.site-header[data-scrolled]::after {
  background: rgba(200, 255, 61, 0.42);
}

.site-header__inner {
  display: flex;
  align-items: center;
  gap: clamp(14px, 2.4vw, 34px);
  width: min(1240px, 100% - var(--gutter) * 2);
  margin-inline: auto;
  min-height: var(--header-h);
}

.site-header__progress {
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 3px;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--kiwi) 0%, var(--teal) 100%);
  transition: transform 0.12s linear;
}

/* ---- 品牌 ---- */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.68rem;
  flex: none;
}

.brand__mark {
  position: relative;
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  flex: none;
  border-radius: 50%;
  background:
    radial-gradient(circle at 50% 50%, var(--card) 0 16%, var(--kiwi-soft) 16% 34%, var(--kiwi) 34% 66%, #86ad22 66% 100%);
  box-shadow: inset 0 0 0 2px rgba(27, 21, 18, 0.88);
  overflow: hidden;
}

.brand__mark::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 50%;
  background: repeating-conic-gradient(from 0deg, rgba(27, 21, 18, 0.42) 0deg 1.6deg, rgba(27, 21, 18, 0) 1.6deg 28deg);
}

.brand__core {
  position: relative;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--card);
  box-shadow: 0 0 0 1.5px rgba(27, 21, 18, 0.75);
}

.brand__type {
  display: flex;
  flex-direction: column;
  line-height: 1;
}

.brand__name {
  font-family: var(--f-narrow);
  font-stretch: condensed;
  font-weight: 800;
  font-size: 1.12rem;
  letter-spacing: 0.07em;
  color: var(--hd-fg);
}

.brand__alias {
  margin-top: 0.36em;
  font-family: var(--f-mono);
  font-size: 0.6rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--hd-fg);
  opacity: 0.62;
}

/* ---- 移动按钮 ---- */
.nav-toggle {
  display: none;
}

/* ---- 导航 ---- */
.site-nav {
  display: flex;
  align-items: center;
  margin-left: auto;
}

.site-nav__head,
.site-nav__foot {
  display: none;
}

.site-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(10px, 1.7vw, 26px);
}

.site-nav__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 0.4em;
  padding: 0.45em 0.1em;
  font-family: var(--f-narrow);
  font-stretch: condensed;
  font-weight: 700;
  font-size: 0.95rem;
  letter-spacing: 0.05em;
  color: var(--hd-fg);
  transition: color 0.2s ease;
}

.site-nav__num { display: none; }

.site-nav__link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 3px;
  background: var(--kiwi);
  transform: scaleX(0);
  transform-origin: 0 50%;
  transition: transform 0.28s cubic-bezier(0.2, 0.9, 0.2, 1);
}

.site-nav__link:hover::after,
.site-nav__link:focus-visible::after {
  transform: scaleX(1);
}

.site-nav__link[aria-current="page"] {
  color: var(--hd-fg);
  font-weight: 800;
}

.site-nav__link[aria-current="page"]::after {
  transform: scaleX(1);
}

/* ---- 头部主行动 ---- */
.header-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.4em;
  margin-left: clamp(12px, 2vw, 28px);
  padding: 0.62em 1.15em;
  font-family: var(--f-narrow);
  font-stretch: condensed;
  font-weight: 800;
  font-size: 0.9rem;
  letter-spacing: 0.08em;
  color: var(--ink);
  background: var(--kiwi);
  border: 1px solid var(--ink);
  border-radius: var(--radius);
  box-shadow: 3px 3px 0 var(--ink);
  transition: transform 0.18s ease, box-shadow 0.18s ease, background-color 0.18s ease;
}

.header-cta:hover,
.header-cta:focus-visible {
  background: var(--kiwi-soft);
  transform: translate(-1px, -1px);
  box-shadow: 5px 5px 0 var(--ink);
}

.site-header[data-scrolled] .header-cta {
  border-color: var(--card);
  box-shadow: 3px 3px 0 rgba(252, 249, 242, 0.82);
}

.site-header[data-scrolled] .header-cta:hover,
.site-header[data-scrolled] .header-cta:focus-visible {
  box-shadow: 5px 5px 0 rgba(252, 249, 242, 0.82);
}

/* ---- 遮罩 ---- */
.nav-scrim { display: none; }

/* ============================================================
   14. 站点页脚
   ============================================================ */
.site-footer {
  position: relative;
  margin-top: clamp(56px, 8vw, 124px);
  background: var(--ink);
  color: rgba(252, 249, 242, 0.78);
  overflow: hidden;
}

.site-footer__grid {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(90deg, rgba(252, 249, 242, 0.06) 1px, transparent 1px),
    linear-gradient(180deg, rgba(252, 249, 242, 0.05) 1px, transparent 1px);
  background-size: 58px 58px;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.95) 0%, rgba(0, 0, 0, 0.12) 100%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.95) 0%, rgba(0, 0, 0, 0.12) 100%);
}

.site-footer__inner {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(0, 0.95fr) minmax(0, 1fr);
  gap: clamp(28px, 4vw, 64px);
  width: min(1200px, 100% - var(--gutter) * 2);
  margin-inline: auto;
  padding: clamp(42px, 6vw, 78px) 0 0;
}

/* ---- 品牌陈述 ---- */
.footer-lead__brand {
  font-family: var(--f-serif);
  font-weight: 800;
  font-size: clamp(1.35rem, 2.4vw, 1.9rem);
  line-height: 1.25;
  color: var(--card);
  letter-spacing: 0.01em;
}

.footer-lead__sep {
  color: var(--kiwi);
  margin: 0 0.28em;
}

.footer-lead__text {
  margin-top: 1rem;
  max-width: 34ch;
  font-size: 0.95rem;
  line-height: 1.8;
  color: rgba(252, 249, 242, 0.68);
}

.footer-lead__stamp {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  margin-top: 1.4rem;
  padding: 0.45em 0.85em;
  font-family: var(--f-mono);
  font-size: 0.66rem;
  letter-spacing: 0.18em;
  color: var(--gold);
  border: 1px solid rgba(201, 164, 92, 0.45);
  border-radius: var(--radius);
}

.footer-lead__dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--kiwi);
  box-shadow: 0 0 0 3px rgba(200, 255, 61, 0.18);
  flex: none;
}

/* ---- 页脚导航 ---- */
.footer-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(20px, 3vw, 38px);
  align-content: start;
}

.footer-nav__title {
  padding-bottom: 0.7rem;
  margin-bottom: 0.9rem;
  font-family: var(--f-mono);
  font-size: 0.68rem;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--gold);
  border-bottom: 1px solid var(--line-light);
}

.footer-nav__list {
  display: flex;
  flex-direction: column;
}

.footer-nav__link {
  display: inline-block;
  padding: 0.32rem 0;
  font-family: var(--f-narrow);
  font-stretch: condensed;
  font-weight: 700;
  font-size: 0.98rem;
  letter-spacing: 0.03em;
  color: rgba(252, 249, 242, 0.82);
  transition: color 0.2s ease;
}

.footer-nav__link::before {
  content: "";
  display: inline-block;
  width: 0;
  height: 1px;
  margin-right: 0;
  vertical-align: middle;
  background: var(--kiwi);
  transition: width 0.22s ease, margin-right 0.22s ease;
}

.footer-nav__link:hover,
.footer-nav__link:focus-visible {
  color: var(--kiwi);
}

.footer-nav__link:hover::before,
.footer-nav__link:focus-visible::before {
  width: 14px;
  margin-right: 0.5em;
}

/* ---- 联系台 ---- */
.footer-contact__title {
  padding-bottom: 0.7rem;
  margin-bottom: 0.9rem;
  font-family: var(--f-mono);
  font-size: 0.68rem;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--gold);
  border-bottom: 1px solid var(--line-light);
}

.footer-contact__row {
  display: grid;
  grid-template-columns: 5.6em minmax(0, 1fr);
  gap: 0.6em;
  padding: 0.5rem 0;
  font-size: 0.9rem;
  border-bottom: 1px dashed rgba(252, 249, 242, 0.14);
}

.footer-contact__row dt {
  padding-top: 0.18em;
  font-family: var(--f-mono);
  font-size: 0.66rem;
  letter-spacing: 0.14em;
  color: rgba(252, 249, 242, 0.48);
}

.footer-contact__row dd {
  margin: 0;
  color: var(--card);
  word-break: break-all;
}

.footer-contact__note {
  margin-top: 1rem;
  max-width: 40ch;
  font-size: 0.76rem;
  line-height: 1.72;
  color: rgba(252, 249, 242, 0.48);
}

/* ---- 底条 ---- */
.footer-base {
  grid-column: 1 / -1;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.8rem 1.6rem;
  margin-top: clamp(28px, 4vw, 54px);
  padding: 1.25rem 0 1.9rem;
  border-top: 1px solid var(--line-light);
  font-family: var(--f-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: rgba(252, 249, 242, 0.5);
}

.footer-base__icp { color: var(--gold); }
.footer-base__meta { color: rgba(252, 249, 242, 0.38); }

/* ============================================================
   15. 返回顶部（由 JS 注入）
   ============================================================ */
.to-top {
  position: fixed;
  right: clamp(14px, 2.4vw, 26px);
  bottom: clamp(14px, 2.4vw, 26px);
  z-index: 45;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  width: 54px;
  padding: 0.55rem 0.2rem 0.6rem;
  font-family: var(--f-mono);
  letter-spacing: 0.1em;
  color: var(--ink);
  background: var(--card);
  border: 1px solid var(--ink);
  border-radius: var(--radius);
  box-shadow: 4px 4px 0 var(--ink);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(14px);
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s ease, background-color 0.2s ease;
}

.to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.to-top:hover,
.to-top:focus-visible {
  background: var(--kiwi);
}

.to-top__arrow {
  font-family: var(--f-mono);
  font-size: 1rem;
  line-height: 1;
}

.to-top__label {
  font-size: 0.6rem;
  letter-spacing: 0.12em;
}

/* ============================================================
   16. 显现动效
   ============================================================ */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.7s ease, transform 0.7s cubic-bezier(0.22, 0.9, 0.24, 1);
}

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

@media (prefers-reduced-motion: reduce) {
  .js [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }
}

/* ============================================================
   17. 响应式
   ============================================================ */
@media (max-width: 1080px) {
  .site-nav__link { font-size: 0.9rem; }
  .brand__alias { display: none; }
}

@media (max-width: 900px) {
  :root { --header-h: 66px; }

  .site-header__inner {
    gap: 12px;
  }

  .header-cta { display: none; }

  .nav-toggle {
    position: relative;
    z-index: 70;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    margin-left: auto;
    padding: 0.5em 0.15em;
    font-family: var(--f-narrow);
    font-stretch: condensed;
    font-weight: 800;
    font-size: 0.84rem;
    letter-spacing: 0.16em;
    color: var(--hd-fg);
    transition: color 0.25s ease;
  }

  .nav-toggle__glyph {
    display: grid;
    gap: 5px;
    width: 22px;
  }

  .nav-toggle__glyph span {
    display: block;
    height: 2px;
    width: 100%;
    background: currentColor;
    transition: transform 0.3s ease, opacity 0.2s ease;
  }

  body.nav-open .nav-toggle { color: var(--card); }

  body.nav-open .nav-toggle__glyph span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }
  body.nav-open .nav-toggle__glyph span:nth-child(2) {
    opacity: 0;
  }
  body.nav-open .nav-toggle__glyph span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

  .site-nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    z-index: 60;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    width: min(88vw, 380px);
    margin: 0;
    padding: 84px 26px 34px;
    overflow-y: auto;
    color: var(--card);
    background: var(--ink);
    border-left: 1px solid rgba(200, 255, 61, 0.28);
    transform: translateX(102%);
    transition: transform 0.42s cubic-bezier(0.22, 0.9, 0.24, 1);
    box-shadow: -34px 0 70px -34px rgba(0, 0, 0, 0.85);
  }

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

  .site-nav__head {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    padding-bottom: 0.85rem;
    margin-bottom: 0.6rem;
    border-bottom: 1px solid var(--line-light);
  }

  .site-nav__head-cn {
    font-family: var(--f-serif);
    font-size: 1.08rem;
    font-weight: 800;
    color: var(--card);
  }

  .site-nav__head-en {
    font-family: var(--f-mono);
    font-size: 0.62rem;
    letter-spacing: 0.24em;
    color: var(--gold);
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .site-nav__item {
    border-bottom: 1px solid rgba(252, 249, 242, 0.12);
  }

  .site-nav__link {
    width: 100%;
    gap: 0.9rem;
    padding: 0.92rem 0.1rem;
    font-size: 1.16rem;
    letter-spacing: 0.06em;
    color: var(--card);
  }

  .site-nav__link::after { display: none; }

  .site-nav__num {
    display: inline-block;
    font-family: var(--f-mono);
    font-size: 0.68rem;
    letter-spacing: 0.1em;
    color: var(--gold);
  }

  .site-nav__link[aria-current="page"] {
    color: var(--kiwi);
  }

  .site-nav__link[aria-current="page"] .site-nav__num {
    color: var(--kiwi);
  }

  .site-nav__foot {
    display: flex;
    flex-direction: column;
    gap: 0.85rem;
    padding-top: 1.5rem;
    margin-top: auto;
  }

  .site-nav__note {
    font-family: var(--f-mono);
    font-size: 0.68rem;
    letter-spacing: 0.12em;
    color: rgba(252, 249, 242, 0.52);
  }

  .nav-scrim {
    display: block;
    position: fixed;
    inset: 0;
    z-index: 55;
    background: rgba(27, 21, 18, 0.56);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.35s ease, visibility 0.35s ease;
  }

  body.nav-open .nav-scrim {
    opacity: 1;
    visibility: visible;
  }

  body.nav-open {
    overflow: hidden;
  }

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

  .footer-lead {
    grid-column: 1 / -1;
  }

  .footer-contact {
    grid-column: 1 / -1;
  }
}

@media (max-width: 620px) {
  .brand__mark { width: 32px; height: 32px; }
  .brand__name { font-size: 1.02rem; }

  .to-top {
    width: 48px;
    padding: 0.5rem 0.2rem;
  }

  .footer-nav {
    grid-template-columns: 1fr;
    gap: 1.4rem;
  }

  .footer-base {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.55rem;
  }

  .footer-contact__row {
    grid-template-columns: 1fr;
    gap: 0.1em;
  }

  .footer-contact__row dt { padding-top: 0; }
}

@media (max-width: 400px) {
  .brand__alias { display: none; }
}