/* ==========================================================================
   球友汇社区 /assets/site.css —— 共享外壳与基础构件
   夜场墨绿 · 电子青 · 暖橙 · 暖纸色
   ========================================================================== */

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

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

body, h1, h2, h3, h4, h5, p, ul, ol, li, figure, blockquote, dl, dd, fieldset {
  margin: 0;
}
ul, ol { padding: 0; list-style: none; }
img, svg, video { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: 0; }
strong, b { font-weight: 700; }

:root {
  /* 色彩体系 */
  --ink: #07120F;
  --deep: #0C2A21;
  --line: #14523F;
  --paper: #F2EAD9;
  --paper-dim: #CFC3A8;
  --cyan: #35F0D0;
  --teal: #0E7A6B;
  --orange: #FF7A3D;
  --orange-ink: #C24A18;
  --chalk: #F7F5EF;
  --black: #101915;

  /* 排版 */
  --font-sans: system-ui, -apple-system, "Segoe UI", "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Source Han Sans SC", "Noto Sans SC", sans-serif;
  --font-mono: ui-monospace, "SF Mono", "JetBrains Mono", "Roboto Mono", Menlo, Consolas,
    "Courier New", monospace;

  /* 尺寸与节奏 */
  --gutter: clamp(18px, 4vw, 56px);
  --header-h: 68px;
  --radius-lg: 26px;
  --radius-md: 16px;
  --radius-sm: 10px;
  --cut: 18px;
  --ease: cubic-bezier(.22, .61, .36, 1);
}

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

body {
  background: var(--ink);
  color: var(--chalk);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  font-weight: 400;
  padding-top: var(--header-h);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
body[data-header-overlay] { padding-top: 0; }

h1, h2, h3, h4 { text-wrap: balance; line-height: 1.2; }
p { text-wrap: pretty; }

main { display: block; }
#main-content:focus { outline: none; }

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 4px;
}
.surface-paper :focus-visible { outline-color: var(--orange-ink); }

/* ------------------------------ 容器与节奏 ------------------------------ */
.wrap {
  width: min(1240px, calc(100% - var(--gutter) * 2));
  margin-inline: auto;
}

.section { padding-block: clamp(48px, 7vw, 96px); }
.section--tight { padding-block: clamp(28px, 4vw, 48px); }

.surface-deep { background: var(--deep); color: var(--chalk); }
.surface-line { background: var(--line); color: var(--chalk); }
.surface-paper {
  background: var(--paper);
  color: var(--black);
}
.surface-paper .rule { background: var(--paper-dim); }

.rule { height: 1px; background: rgba(247, 245, 239, .14); border: 0; }

/* ------------------------------ 跳转链接 ------------------------------ */
.skip-link {
  position: fixed;
  top: 0;
  left: 50%;
  z-index: 200;
  padding: 12px 24px;
  border-radius: 0 0 16px 16px;
  background: var(--cyan);
  color: var(--ink);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .04em;
  transform: translate(-50%, -140%);
  transition: transform .18s var(--ease);
}
.skip-link:focus { transform: translate(-50%, 0); }

/* ------------------------------ 品牌字标 ------------------------------ */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: none;
}
.brand__mark {
  position: relative;
  width: 26px;
  height: 26px;
  flex: none;
  border: 2px solid var(--cyan);
  border-radius: 50%;
}
.brand__mark::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--orange);
  transform: translate(-50%, -50%);
}
.brand__mark::after {
  content: "";
  position: absolute;
  top: -2px;
  bottom: -2px;
  left: 50%;
  width: 1px;
  background: rgba(53, 240, 208, .45);
  transform: translateX(-50%);
}
.brand__name {
  font-size: 17px;
  font-weight: 800;
  letter-spacing: .06em;
  color: var(--chalk);
  white-space: nowrap;
}
.brand__name em {
  font-style: normal;
  font-weight: 500;
  color: var(--cyan);
  margin-left: 3px;
  letter-spacing: .1em;
}

/* ------------------------------ 头部 ------------------------------ */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 90;
  background-color: transparent;
  background-image: linear-gradient(180deg, rgba(7, 18, 15, .72) 0%, rgba(7, 18, 15, .12) 62%, rgba(7, 18, 15, 0) 100%);
  border-bottom: 1px solid transparent;
  transition: background-color .24s var(--ease), border-color .24s var(--ease), box-shadow .24s var(--ease);
}
.site-header[data-scrolled="true"] {
  background-color: rgba(7, 18, 15, .97);
  background-image: none;
  border-bottom-color: rgba(53, 240, 208, .22);
  box-shadow: 0 18px 42px -30px rgba(0, 0, 0, .95);
}
.site-header[data-nav-open="true"] {
  background-color: var(--ink);
  background-image: none;
  border-bottom-color: rgba(53, 240, 208, .22);
}

.site-header__inner {
  width: min(1240px, calc(100% - var(--gutter) * 2));
  margin-inline: auto;
  min-height: var(--header-h);
  display: flex;
  align-items: center;
  gap: clamp(12px, 2vw, 28px);
  padding-block: 10px;
}

.site-header__brand {
  display: flex;
  align-items: center;
  gap: 14px;
  flex: none;
}

/* 版本胶囊 */
.version-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 12px 5px 10px;
  border: 1px solid rgba(53, 240, 208, .38);
  border-radius: 999px;
  background: rgba(53, 240, 208, .09);
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1;
  letter-spacing: .12em;
  color: var(--cyan);
  white-space: nowrap;
}
.version-pill__dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--orange);
  box-shadow: 0 0 0 3px rgba(255, 122, 61, .18);
}
.version-pill__label { opacity: .72; }
.version-pill__num { font-weight: 700; letter-spacing: .06em; }

/* 移动菜单按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 9px 15px;
  border: 1px solid rgba(247, 245, 239, .28);
  border-radius: 999px;
  background: rgba(7, 18, 15, .55);
  color: var(--chalk);
  font-size: 12px;
  letter-spacing: .16em;
  cursor: pointer;
  transition: border-color .2s var(--ease), background .2s var(--ease);
}
.nav-toggle:hover { border-color: var(--cyan); background: rgba(53, 240, 208, .12); }
.nav-toggle__bars { display: grid; gap: 4px; width: 16px; }
.nav-toggle__bars i {
  display: block;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
  transition: transform .2s var(--ease), opacity .2s var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars i:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* 导航 */
.site-nav {
  display: flex;
  align-items: center;
  margin-left: auto;
}
.site-nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
}
.site-nav__link {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border-radius: 999px;
  font-size: 14px;
  line-height: 1.4;
  color: rgba(247, 245, 239, .8);
  white-space: nowrap;
  transition: color .2s var(--ease), background .2s var(--ease);
}
.site-nav__link:hover { color: var(--chalk); background: rgba(247, 245, 239, .08); }
.site-nav__link[aria-current="page"] {
  color: var(--ink);
  background: var(--cyan);
  font-weight: 700;
}
.site-nav__idx { display: none; }
.site-nav__desc { display: none; }
.site-nav__foot { display: none; }

/* ------------------------------ 按钮 ------------------------------ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 13px 24px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: .02em;
  cursor: pointer;
  transition: background .2s var(--ease), color .2s var(--ease), border-color .2s var(--ease), transform .2s var(--ease);
}
.btn:hover { transform: translateY(-2px); }
.btn--primary { background: var(--cyan); color: var(--ink); }
.btn--primary:hover { background: #5ef7dc; }
.btn--ghost { border-color: rgba(247, 245, 239, .32); color: var(--chalk); }
.btn--ghost:hover { border-color: var(--cyan); color: var(--cyan); }
.btn--orange { background: var(--orange); color: #2A0B02; }
.btn--orange:hover { background: #ff8d5b; }
.btn--teal { background: var(--teal); color: var(--chalk); }
.btn--teal:hover { background: #108b79; }
.surface-paper .btn--ghost { border-color: rgba(16, 25, 21, .28); color: var(--black); }
.surface-paper .btn--ghost:hover { border-color: var(--orange-ink); color: var(--orange-ink); }

/* ------------------------------ 面包屑 ------------------------------ */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding-block: 18px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: rgba(247, 245, 239, .6);
}
.breadcrumb a { color: var(--cyan); }
.breadcrumb a:hover { text-decoration: underline; }
.breadcrumb__sep { opacity: .5; }

/* ------------------------------ 文字构件 ------------------------------ */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--cyan);
}
.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: currentColor;
  flex: none;
}
.surface-paper .eyebrow { color: var(--orange-ink); }

.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: -.01em;
}

.h-display {
  font-size: clamp(2.6rem, 8vw, 7rem);
  font-weight: 800;
  line-height: .92;
  letter-spacing: -.03em;
  transform: skewX(-4deg);
  transform-origin: left bottom;
}
.slant { display: inline-block; transform: skewX(-5deg); }

.stat { display: grid; gap: 4px; }
.stat__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1;
  letter-spacing: -.02em;
  color: var(--cyan);
}
.stat__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: rgba(247, 245, 239, .58);
}
.surface-paper .stat__num { color: var(--orange-ink); }
.surface-paper .stat__label { color: rgba(16, 25, 21, .55); }

/* ------------------------------ 网格与卡片 ------------------------------ */
.grid { display: grid; gap: clamp(14px, 2vw, 24px); }
.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)); }

.card {
  position: relative;
  background: var(--deep);
  border: 1px solid rgba(53, 240, 208, .16);
  border-radius: var(--radius-lg);
  padding: clamp(18px, 2.4vw, 28px);
  transition: border-color .24s var(--ease), transform .24s var(--ease), background .24s var(--ease);
}
.card:hover {
  border-color: rgba(53, 240, 208, .48);
  transform: translateY(-4px);
}
.surface-paper .card {
  background: #FBF6EA;
  border-color: rgba(16, 25, 21, .12);
}
.surface-paper .card:hover { border-color: rgba(194, 74, 24, .5); }
.card__tag {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: rgba(247, 245, 239, .55);
}
.surface-paper .card__tag { color: rgba(16, 25, 21, .5); }

.cut {
  clip-path: polygon(
    0 0,
    calc(100% - var(--cut)) 0,
    100% var(--cut),
    100% 100%,
    var(--cut) 100%,
    0 calc(100% - var(--cut))
  );
}

/* ------------------------------ 标签 ------------------------------ */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  border: 1px solid currentColor;
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  line-height: 1.6;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--cyan);
  white-space: nowrap;
}
.tag--orange { color: var(--orange); }
.tag--paper { color: var(--orange-ink); }

/* ------------------------------ 主题筛选 ------------------------------ */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
}
.filter-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 16px;
  border: 1px solid rgba(53, 240, 208, .42);
  border-radius: 999px;
  background: transparent;
  color: var(--chalk);
  font-size: 13px;
  letter-spacing: .04em;
  cursor: pointer;
  transition: background .2s var(--ease), color .2s var(--ease), border-color .2s var(--ease), transform .2s var(--ease);
}
.filter-chip:hover { background: rgba(53, 240, 208, .14); transform: translateY(-2px); }
.filter-chip[aria-pressed="true"] {
  background: var(--cyan);
  border-color: var(--cyan);
  color: var(--ink);
  font-weight: 700;
}
.filter-chip__count {
  font-family: var(--font-mono);
  font-size: 11px;
  opacity: .68;
}
.surface-paper .filter-chip {
  border-color: rgba(16, 25, 21, .24);
  color: var(--black);
}
.surface-paper .filter-chip:hover { background: rgba(194, 74, 24, .12); }
.surface-paper .filter-chip[aria-pressed="true"] {
  background: var(--black);
  border-color: var(--black);
  color: var(--paper);
}
.filter-empty {
  padding: 24px;
  border: 1px dashed rgba(247, 245, 239, .28);
  border-radius: var(--radius-md);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: .08em;
  color: rgba(247, 245, 239, .6);
}
.surface-paper .filter-empty {
  border-color: rgba(16, 25, 21, .24);
  color: rgba(16, 25, 21, .6);
}
[hidden] { display: none !important; }

/* ------------------------------ 正文容器 ------------------------------ */
.prose {
  max-width: 68ch;
  font-size: 17px;
  line-height: 1.75;
}
.prose > * + * { margin-top: 1.1em; }
.prose h2 {
  font-size: clamp(1.35rem, 2.4vw, 1.75rem);
  font-weight: 700;
  letter-spacing: -.01em;
  margin-top: 1.8em;
}
.prose h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-top: 1.6em;
}
.prose ul, .prose ol {
  padding-left: 1.2em;
  list-style: disc;
}
.prose ol { list-style: decimal; }
.prose li + li { margin-top: .5em; }
.prose a {
  color: var(--cyan);
  border-bottom: 1px solid rgba(53, 240, 208, .45);
}
.surface-paper .prose a {
  color: var(--orange-ink);
  border-bottom-color: rgba(194, 74, 24, .45);
}
.prose blockquote {
  padding-left: 18px;
  border-left: 3px solid var(--cyan);
  color: rgba(247, 245, 239, .82);
}
.surface-paper .prose blockquote {
  border-left-color: var(--orange-ink);
  color: rgba(16, 25, 21, .8);
}
.prose details {
  border: 1px solid rgba(247, 245, 239, .18);
  border-radius: var(--radius-md);
  padding: 14px 18px;
}
.surface-paper .prose details { border-color: rgba(16, 25, 21, .16); }
.prose summary { cursor: pointer; font-weight: 600; }

/* ------------------------------ 图片容器 ------------------------------ */
.media {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-lg);
  background: linear-gradient(150deg, var(--deep) 0%, var(--line) 100%);
  aspect-ratio: 16 / 9;
  isolation: isolate;
}
.media--wide { aspect-ratio: 21 / 9; }
.media--tall { aspect-ratio: 3 / 4; }
.media--square { aspect-ratio: 1 / 1; }
.media > img,
.media > picture > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.media::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(53, 240, 208, .1) 1px, transparent 1px),
    linear-gradient(90deg, rgba(53, 240, 208, .1) 1px, transparent 1px);
  background-size: 48px 48px;
  pointer-events: none;
  z-index: 1;
}
.media::after {
  content: "";
  position: absolute;
  inset: 10px;
  border: 1px solid rgba(247, 245, 239, .3);
  border-radius: calc(var(--radius-lg) - 10px);
  pointer-events: none;
  z-index: 2;
}
.media__frame {
  position: absolute;
  inset: auto 18px 18px auto;
  z-index: 3;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 12px;
  border-radius: 999px;
  background: rgba(7, 18, 15, .78);
  border: 1px solid rgba(53, 240, 208, .45);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--cyan);
}
.media__tag {
  position: absolute;
  inset: 18px auto auto 18px;
  z-index: 3;
  padding: 4px 11px;
  border-radius: 999px;
  background: var(--orange);
  color: #2A0B02;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .1em;
}

/* ------------------------------ 页脚 ------------------------------ */
.site-footer {
  position: relative;
  margin-top: clamp(56px, 8vw, 104px);
  background: var(--ink);
  color: var(--chalk);
}
.site-footer__band {
  position: relative;
  height: 8px;
  background: var(--orange);
  overflow: hidden;
}
.site-footer__band::before {
  content: "";
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(100deg, var(--ink) 0 3px, transparent 3px 48px);
  opacity: .85;
}
.site-footer__main {
  padding-block: clamp(40px, 5.5vw, 72px) clamp(26px, 3.5vw, 40px);
}
.site-footer__top {
  display: grid;
  grid-template-columns: minmax(200px, .85fr) minmax(0, 2.4fr);
  gap: clamp(24px, 4vw, 56px);
  align-items: start;
}
.site-footer__brand { display: grid; gap: 12px; align-content: start; }
.site-footer__note {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: rgba(247, 245, 239, .55);
}
.site-footer__matrix {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: clamp(14px, 2vw, 26px);
}
.foot-col {
  padding-top: 14px;
  border-top: 2px solid var(--line);
  transition: border-color .24s var(--ease);
}
.foot-col:hover { border-top-color: var(--cyan); }
.foot-col__title {
  font-size: 15px;
  font-weight: 700;
  letter-spacing: .04em;
  line-height: 1.5;
}
.foot-col__link {
  display: inline-block;
  color: var(--chalk);
  border-bottom: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}
.foot-col__link:hover { color: var(--cyan); border-bottom-color: var(--cyan); }
.foot-col__desc {
  margin-top: 8px;
  font-size: 12.5px;
  line-height: 1.7;
  color: rgba(247, 245, 239, .58);
}
.site-footer__service {
  margin-top: clamp(28px, 4vw, 44px);
  padding-top: clamp(16px, 2.4vw, 24px);
  border-top: 1px solid rgba(247, 245, 239, .14);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: rgba(247, 245, 239, .62);
}
.site-footer__legal {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 28px;
  margin-top: 14px;
  font-size: 13px;
  color: rgba(247, 245, 239, .7);
}
.site-footer__icp { color: var(--cyan); letter-spacing: .04em; }
.site-footer__contact { font-size: 12.5px; }
.site-footer__addr { font-size: 12.5px; }
.site-footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 24px;
  margin-top: clamp(20px, 3vw, 32px);
  padding-top: 18px;
  border-top: 1px solid rgba(247, 245, 239, .1);
  font-size: 12.5px;
  color: rgba(247, 245, 239, .58);
}
.site-footer__links {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 20px;
}
.site-footer__links a {
  color: rgba(247, 245, 239, .7);
  border-bottom: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}
.site-footer__links a:hover { color: var(--cyan); border-bottom-color: var(--cyan); }

/* ------------------------------ 响应式 ------------------------------ */
@media (max-width: 1180px) {
  .site-nav__link { padding: 8px 10px; font-size: 13.5px; }
}

@media (max-width: 1080px) {
  .version-pill { display: none; }
}

@media (max-width: 1000px) {
  .site-footer__top { grid-template-columns: minmax(0, 1fr); }
  .site-footer__matrix { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 900px) {
  :root { --header-h: 62px; }

  .nav-toggle {
    display: inline-flex;
    order: 2;
    margin-left: auto;
  }

  .site-header__inner { gap: 12px; }

  .site-nav {
    position: fixed;
    inset: 0;
    z-index: 60;
    display: none;
    flex-direction: column;
    align-items: stretch;
    margin-left: 0;
    overflow-y: auto;
    overscroll-behavior: contain;
    padding: calc(var(--header-h) + 24px) var(--gutter) 48px;
    background-color: var(--ink);
    background-image: radial-gradient(130% 70% at 85% 0%, var(--deep) 0%, var(--ink) 62%);
  }
  .site-nav[data-open="true"] { display: flex; }

  .site-nav__list {
    display: grid;
    grid-template-columns: minmax(0, 1fr);
    gap: 10px;
    flex: none;
  }
  .site-nav__link {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    align-items: baseline;
    gap: 2px 14px;
    padding: 16px 18px;
    border: 1px solid rgba(53, 240, 208, .18);
    border-radius: var(--radius-md);
    background: var(--deep);
    font-size: 17px;
    font-weight: 700;
    color: var(--chalk);
    white-space: normal;
  }
  .site-nav__link:hover { background: rgba(20, 82, 63, .55); }
  .site-nav__link[aria-current="page"] {
    background: var(--cyan);
    border-color: var(--cyan);
    color: var(--ink);
  }
  .site-nav__idx {
    display: block;
    grid-row: span 2;
    font-size: 12px;
    font-weight: 400;
    letter-spacing: .2em;
    color: var(--cyan);
    padding-top: 3px;
  }
  .site-nav__link[aria-current="page"] .site-nav__idx { color: var(--ink); opacity: .7; }
  .site-nav__label { display: block; }
  .site-nav__desc {
    display: block;
    grid-column: 2;
    font-size: 12.5px;
    font-weight: 400;
    line-height: 1.6;
    letter-spacing: .02em;
    color: rgba(247, 245, 239, .58);
  }
  .site-nav__link[aria-current="page"] .site-nav__desc { color: rgba(7, 18, 15, .68); }

  .site-nav__foot {
    display: block;
    margin-top: auto;
    padding-top: 28px;
    font-family: var(--font-mono);
    font-size: 11.5px;
    letter-spacing: .14em;
    color: rgba(247, 245, 239, .5);
  }

  .grid--3, .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .h-display { transform: skewX(-3deg); }
}

@media (max-width: 640px) {
  body { font-size: 15.5px; }
  .grid--2, .grid--3, .grid--4 { grid-template-columns: minmax(0, 1fr); }
  .site-footer__matrix { grid-template-columns: minmax(0, 1fr); }
  .site-footer__bottom { justify-content: flex-start; }
  .brand__name { font-size: 16px; }
  .prose { font-size: 16px; }
}

/* ------------------------------ 动效降级 ------------------------------ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    transition-delay: 0ms !important;
  }
  .btn:hover,
  .card:hover,
  .filter-chip:hover,
  .site-nav__link,
  .nav-toggle__bars i { transform: none; }
}