/* ==========================================================================
   biwei-sprint.com.cn — 共享外壳样式 / assets/site.css
   夜间球场灯光体系：深海蓝底、电光青结构线、珊瑚橙关键数据
   ========================================================================== */

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

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

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

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

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

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

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

hr{border:0;height:1px;background:rgba(53,230,255,.14);}

/* ---------- 2. design tokens ---------- */
:root{
  --c-deep:#041726;
  --c-navy:#082A44;
  --c-cyan:#35E6FF;
  --c-cyan-soft:#A8F6FF;
  --c-coral:#FF6B4A;
  --c-mist:#EAF6FA;
  --c-steel:#7E9EB0;
  --c-ink:#020D16;
  --c-grid:#12384F;

  --c-line:rgba(53,230,255,.14);
  --c-line-soft:rgba(126,158,176,.22);

  --font-display:"Oswald","Barlow Condensed","Noto Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-serif:"Noto Serif SC","Songti SC","Source Han Serif SC",Georgia,"Times New Roman",serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;

  --radius-l:28px;
  --radius-m:20px;
  --radius-pill:999px;

  --shell:1200px;
  --gutter:clamp(18px,4vw,40px);
  --header-h:84px;
  --ease:cubic-bezier(.22,.68,.36,1);
}

/* ---------- 3. base ---------- */
html,body{min-height:100%;}

body{
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.7;
  color:var(--c-mist);
  background-color:var(--c-deep);
  background-image:
    radial-gradient(1100px 620px at 84% -6%,rgba(53,230,255,.16),transparent 62%),
    radial-gradient(880px 520px at 2% 4%,rgba(255,107,74,.09),transparent 60%),
    linear-gradient(180deg,#041726 0%,#041726 46%,#020D16 100%);
  background-repeat:no-repeat;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}

body::before{
  content:"";
  position:fixed;
  inset:0;
  z-index:0;
  pointer-events:none;
  background-image:
    repeating-linear-gradient(90deg,rgba(53,230,255,.05) 0 1px,transparent 1px 120px),
    repeating-linear-gradient(0deg,rgba(53,230,255,.032) 0 1px,transparent 1px 120px);
  -webkit-mask-image:radial-gradient(120% 78% at 50% 0%,#000 18%,transparent 76%);
  mask-image:radial-gradient(120% 78% at 50% 0%,#000 18%,transparent 76%);
}

main{display:block;position:relative;z-index:1;padding-top:clamp(92px,11vw,120px);}
main[data-flush]{padding-top:0;}

#main-content{scroll-margin-top:120px;}

h1,h2,h3,h4{
  font-family:var(--font-display);
  font-weight:600;
  line-height:1.1;
  letter-spacing:.01em;
  color:var(--c-mist);
}

::selection{background:var(--c-cyan);color:#03151f;}

:focus-visible{
  outline:2px solid var(--c-cyan);
  outline-offset:3px;
  border-radius:8px;
}

/* ---------- 4. 排版工具 ---------- */
.shell{
  width:min(var(--shell),calc(100% - var(--gutter) * 2));
  margin-inline:auto;
}

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

.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:10px;
  font-family:var(--font-mono);
  font-size:11.5px;
  font-weight:500;
  letter-spacing:.26em;
  text-transform:uppercase;
  color:var(--c-cyan);
}

.eyebrow::before{
  content:"";
  width:26px;
  height:1px;
  background:currentColor;
  opacity:.75;
}

.chapter{
  display:block;
  font-family:var(--font-display);
  font-size:clamp(46px,7.4vw,88px);
  font-weight:600;
  line-height:.86;
  letter-spacing:-.02em;
  color:rgba(53,230,255,.26);
  transition:color .4s var(--ease),-webkit-text-stroke-color .4s var(--ease);
}

@supports (-webkit-text-stroke:1px #000){
  .chapter{
    color:transparent;
    -webkit-text-stroke:1px rgba(53,230,255,.5);
  }
}

[data-section].is-current .chapter{
  color:var(--c-cyan);
  -webkit-text-stroke-color:var(--c-cyan);
}

.lede{
  font-family:var(--font-serif);
  font-size:clamp(17px,2vw,21px);
  line-height:1.75;
  color:rgba(234,246,250,.9);
  max-width:34em;
}

.prose{
  max-width:38em;
  font-size:17px;
  line-height:1.8;
  color:rgba(234,246,250,.88);
}

.prose p + p{margin-top:1.05em;}

.prose h2{
  font-size:clamp(22px,2.6vw,30px);
  margin-top:1.9em;
  margin-bottom:.55em;
}

.prose h3{
  font-size:clamp(18px,2vw,22px);
  margin-top:1.6em;
  margin-bottom:.4em;
}

.prose ul,.prose ol{
  margin:1em 0;
  padding-left:1.2em;
  list-style:disc;
}

.prose li + li{margin-top:.35em;}

.prose a{
  color:var(--c-cyan);
  text-decoration:underline;
  text-underline-offset:3px;
  text-decoration-thickness:1px;
}

.prose a:hover{color:var(--c-cyan-soft);}

.prose strong{color:var(--c-mist);font-weight:600;}

.prose blockquote{
  margin:1.4em 0;
  padding:14px 0 14px 20px;
  border-left:2px solid var(--c-cyan);
  font-family:var(--font-serif);
  color:rgba(234,246,250,.92);
}

/* ---------- 5. 章节 ---------- */
.section{
  position:relative;
  padding-block:clamp(48px,7vw,104px);
}

.section + .section{border-top:1px solid rgba(53,230,255,.08);}

.section-head{
  display:flex;
  flex-wrap:wrap;
  align-items:flex-end;
  gap:clamp(12px,2.2vw,30px);
  margin-bottom:clamp(22px,3.2vw,42px);
}

.section-title{
  font-size:clamp(26px,4vw,40px);
  line-height:1.05;
  letter-spacing:0;
}

.section-lead{
  max-width:34em;
  font-size:15px;
  line-height:1.75;
  color:var(--c-steel);
}

/* ---------- 6. 网格 ---------- */
.grid{display:grid;gap:clamp(16px,2.4vw,30px);}

.grid--2{grid-template-columns:repeat(2,minmax(0,1fr));}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr));}
.grid--split{grid-template-columns:minmax(0,1.45fr) minmax(0,1fr);}
.grid--aside{grid-template-columns:minmax(0,1fr) minmax(240px,300px);}

/* ---------- 7. 卡片 ---------- */
.card{
  position:relative;
  padding:clamp(18px,2.2vw,28px);
  border-radius:var(--radius-l);
  background:linear-gradient(180deg,rgba(8,42,68,.86),rgba(4,23,38,.92));
  border:1px solid rgba(53,230,255,.14);
  box-shadow:inset 0 1px 0 rgba(168,246,255,.06);
}

.card--quiet{
  background:rgba(8,42,68,.48);
  border-color:var(--c-line-soft);
}

.card--accent{
  border-color:rgba(53,230,255,.42);
  background:linear-gradient(180deg,rgba(53,230,255,.13),rgba(4,23,38,.92));
}

/* ---------- 8. 按钮 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:10px;
  padding:12px 22px;
  border-radius:var(--radius-pill);
  border:1px solid transparent;
  font-family:var(--font-body);
  font-size:14px;
  font-weight:500;
  letter-spacing:.06em;
  line-height:1.2;
  text-align:center;
  white-space:nowrap;
  transition:background .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease),transform .2s var(--ease);
}

.btn--primary{
  background:var(--c-cyan);
  color:#03151f;
  box-shadow:0 16px 34px -20px rgba(53,230,255,.95);
}

.btn--primary:hover{background:var(--c-cyan-soft);transform:translateY(-1px);}

.btn--ghost{
  border-color:rgba(53,230,255,.42);
  color:var(--c-cyan-soft);
  background:rgba(53,230,255,.05);
}

.btn--ghost:hover{background:rgba(53,230,255,.15);border-color:var(--c-cyan);}

.btn--coral{
  background:var(--c-coral);
  color:#1b0703;
  box-shadow:0 16px 34px -20px rgba(255,107,74,.9);
}

.btn--coral:hover{background:#ff8b70;transform:translateY(-1px);}

.btn--lg{padding:15px 30px;font-size:15px;}

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

/* ---------- 9. 标签与数据 ---------- */
.pill{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:4px 12px;
  border-radius:var(--radius-pill);
  border:1px solid rgba(53,230,255,.3);
  background:rgba(53,230,255,.08);
  color:var(--c-cyan-soft);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
  text-transform:uppercase;
  white-space:nowrap;
}

.pill--coral{
  border-color:rgba(255,107,74,.45);
  background:rgba(255,107,74,.14);
  color:#ffbba9;
}

.pill--steel{
  border-color:var(--c-line-soft);
  background:rgba(126,158,176,.1);
  color:var(--c-steel);
}

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

.stat__value{
  font-family:var(--font-mono);
  font-variant-numeric:tabular-nums;
  font-size:clamp(26px,3.4vw,38px);
  font-weight:500;
  line-height:1.05;
  letter-spacing:-.02em;
  color:var(--c-mist);
}

.stat__value--coral{color:var(--c-coral);}

.stat__label{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.16em;
  text-transform:uppercase;
  color:var(--c-steel);
}

.data-bar{
  height:8px;
  border-radius:var(--radius-pill);
  background:var(--c-grid);
  overflow:hidden;
}

.data-bar__fill{
  display:block;
  height:100%;
  width:var(--value,50%);
  border-radius:inherit;
  background:linear-gradient(90deg,var(--c-cyan),var(--c-cyan-soft));
  transition:width .6s var(--ease);
}

.data-bar__fill--coral{
  background:linear-gradient(90deg,var(--c-coral),#ffb59f);
}

/* ---------- 10. 图像容器 ---------- */
.figure{
  margin:0;
  position:relative;
  overflow:hidden;
  border-radius:var(--radius-l);
  border:1px solid rgba(53,230,255,.15);
  background:linear-gradient(160deg,#082A44,#020D16);
}

.figure__media{
  position:relative;
  aspect-ratio:16 / 9;
  overflow:hidden;
  background:
    radial-gradient(circle at 28% 18%,rgba(53,230,255,.22),transparent 58%),
    repeating-linear-gradient(90deg,rgba(53,230,255,.07) 0 1px,transparent 1px 64px),
    linear-gradient(180deg,#062334,#020D16);
}

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

.figure__caption{
  padding:14px 18px;
  border-top:1px solid rgba(53,230,255,.12);
  font-size:13px;
  line-height:1.6;
  color:var(--c-steel);
}

.figure--wide .figure__media{aspect-ratio:21 / 9;}
.figure--tall .figure__media{aspect-ratio:4 / 5;}

/* ---------- 11. 面包屑 ---------- */
.breadcrumbs{
  font-size:13px;
  letter-spacing:.04em;
  color:var(--c-steel);
}

.breadcrumbs__list{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
}

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

.breadcrumbs__item:not(:last-child)::after{
  content:"/";
  color:var(--c-grid);
}

.breadcrumbs a:hover{color:var(--c-cyan-soft);}

.breadcrumbs [aria-current="page"]{color:var(--c-mist);}

/* ---------- 12. 跳转链接与阅读进度 ---------- */
.skip-link{
  position:fixed;
  top:10px;
  left:50%;
  transform:translate(-50%,-180%);
  z-index:200;
  padding:10px 22px;
  border-radius:var(--radius-pill);
  background:var(--c-cyan);
  color:#03151f;
  font-size:14px;
  font-weight:500;
  transition:transform .2s var(--ease);
}

.skip-link:focus{transform:translate(-50%,0);}

.read-progress{
  position:fixed;
  top:0;
  left:0;
  right:0;
  height:2px;
  z-index:150;
  background:rgba(53,230,255,.12);
  pointer-events:none;
}

.read-progress__fill{
  display:block;
  height:100%;
  width:0;
  background:linear-gradient(90deg,var(--c-cyan) 0%,var(--c-cyan-soft) 58%,var(--c-coral) 100%);
}

/* ---------- 13. 头部 ---------- */
.site-header{
  position:fixed;
  top:0;
  left:0;
  right:0;
  z-index:120;
  padding:16px 0 0;
  transition:padding .28s var(--ease);
}

.header-shell{
  display:flex;
  align-items:center;
  gap:16px;
  width:min(var(--shell),calc(100% - var(--gutter) * 2));
  margin-inline:auto;
  padding:9px 12px 9px 18px;
  border-radius:var(--radius-pill);
  border:1px solid rgba(53,230,255,.18);
  background:linear-gradient(180deg,rgba(8,42,68,.94),rgba(4,23,38,.86));
  box-shadow:0 22px 46px -30px rgba(2,13,22,.95),inset 0 1px 0 rgba(168,246,255,.08);
  -webkit-backdrop-filter:blur(14px);
  backdrop-filter:blur(14px);
  transition:padding .28s var(--ease),border-color .28s var(--ease),background .28s var(--ease);
}

.site-header.is-compact{padding-top:8px;}

.site-header.is-compact .header-shell{
  padding:5px 10px 5px 14px;
  border-color:rgba(53,230,255,.3);
  background:linear-gradient(180deg,rgba(6,32,52,.97),rgba(2,13,22,.94));
}

/* 品牌 */
.brand{
  display:flex;
  align-items:center;
  gap:11px;
  flex:0 0 auto;
  padding:2px 4px 2px 0;
}

.brand__mark{
  position:relative;
  width:36px;
  height:36px;
  flex:0 0 auto;
  border-radius:13px;
  overflow:hidden;
  background:linear-gradient(150deg,var(--c-cyan) 0%,#0a6f92 58%,var(--c-navy) 100%);
  box-shadow:inset 0 0 0 1px rgba(2,13,22,.4),0 8px 18px -10px rgba(53,230,255,.85);
}

.brand__mark::before{
  content:"";
  position:absolute;
  right:-10px;
  bottom:-8px;
  width:28px;
  height:46px;
  border-radius:6px;
  background:rgba(2,13,22,.55);
  transform:rotate(28deg);
}

.brand__mark::after{
  content:"";
  position:absolute;
  left:8px;
  top:8px;
  width:9px;
  height:9px;
  border-radius:50%;
  background:var(--c-coral);
  box-shadow:0 0 10px rgba(255,107,74,.9);
}

.brand__text{
  display:flex;
  flex-direction:column;
  line-height:1.15;
}

.brand__name{
  font-family:var(--font-display);
  font-size:18px;
  font-weight:600;
  letter-spacing:.08em;
  color:var(--c-mist);
}

.brand__tag{
  font-size:10.5px;
  letter-spacing:.2em;
  color:var(--c-steel);
}

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

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

.site-nav__link{
  display:inline-block;
  padding:9px 13px;
  border-radius:var(--radius-pill);
  border:1px solid transparent;
  font-size:13.5px;
  letter-spacing:.05em;
  color:rgba(234,246,250,.74);
  transition:color .2s var(--ease),background .2s var(--ease),border-color .2s var(--ease);
}

.site-nav__link:hover{
  color:var(--c-cyan-soft);
  background:rgba(53,230,255,.08);
}

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

.site-nav__link[aria-current="page"]{
  color:#03151f;
  background:var(--c-cyan);
  border-color:rgba(168,246,255,.6);
}

.site-nav__cta{margin-left:8px;font-size:13px;padding:10px 18px;}

/* 移动开关 */
.nav-toggle{
  display:none;
  align-items:center;
  gap:9px;
  margin-left:auto;
  padding:10px 16px;
  border-radius:var(--radius-pill);
  border:1px solid rgba(53,230,255,.32);
  color:var(--c-cyan-soft);
  font-size:12.5px;
  letter-spacing:.14em;
  transition:background .2s var(--ease),border-color .2s var(--ease);
}

.nav-toggle:hover{background:rgba(53,230,255,.1);}

.nav-toggle__bars{
  position:relative;
  display:block;
  width:18px;
  height:12px;
}

.nav-toggle__bars span{
  position:absolute;
  left:0;
  right:0;
  height:2px;
  border-radius:2px;
  background:currentColor;
  transition:transform .24s var(--ease);
}

.nav-toggle__bars span:nth-child(1){top:0;}
.nav-toggle__bars span:nth-child(2){bottom:0;}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1){
  transform:translateY(5px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2){
  transform:translateY(-5px) rotate(-45deg);
}

/* ---------- 14. 页脚 ---------- */
.site-footer{
  position:relative;
  z-index:1;
  margin-top:clamp(48px,7vw,110px);
  padding:clamp(46px,6vw,88px) 0 26px;
  background:linear-gradient(180deg,#03161f 0%,#020D16 72%);
  border-top:1px solid rgba(53,230,255,.16);
  overflow:hidden;
}

.site-footer::before{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background-image:repeating-linear-gradient(90deg,rgba(53,230,255,.05) 0 1px,transparent 1px 96px);
  -webkit-mask-image:linear-gradient(180deg,#000,transparent 82%);
  mask-image:linear-gradient(180deg,#000,transparent 82%);
}

.site-footer .shell{position:relative;z-index:1;}

.footer-top{
  display:grid;
  grid-template-columns:minmax(0,1.55fr) minmax(0,1fr) minmax(0,1.15fr);
  gap:clamp(26px,4vw,60px);
  align-items:start;
}

.footer-brand__name{
  display:block;
  font-family:var(--font-display);
  font-size:clamp(32px,5.4vw,60px);
  font-weight:600;
  line-height:.94;
  letter-spacing:-.01em;
  color:var(--c-mist);
}

@supports (-webkit-background-clip:text){
  .footer-brand__name{
    background:linear-gradient(118deg,var(--c-mist) 10%,var(--c-cyan) 60%,var(--c-steel) 100%);
    -webkit-background-clip:text;
    background-clip:text;
    color:transparent;
  }
}

.footer-brand__text{
  margin-top:14px;
  max-width:32em;
  font-size:14.5px;
  line-height:1.75;
  color:var(--c-steel);
}

.footer-brand__cta{margin-top:22px;}

.footer-cols{
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:clamp(18px,3vw,32px);
}

.footer-col__title{
  margin-bottom:14px;
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.24em;
  text-transform:uppercase;
  color:var(--c-cyan);
}

.footer-links a{
  display:inline-block;
  padding:5px 0;
  font-size:14px;
  color:rgba(234,246,250,.76);
  transition:color .2s var(--ease);
}

.footer-links a:hover{color:var(--c-cyan-soft);}

.footer-contact__row{
  display:grid;
  grid-template-columns:44px minmax(0,1fr);
  gap:10px;
  padding:9px 0;
  border-bottom:1px dashed rgba(126,158,176,.24);
}

.footer-contact__label{
  font-family:var(--font-mono);
  font-size:10.5px;
  letter-spacing:.16em;
  text-transform:uppercase;
  color:var(--c-steel);
  padding-top:2px;
}

.footer-contact__value{
  font-size:14px;
  line-height:1.6;
  word-break:break-word;
  color:var(--c-mist);
}

.footer-note{
  margin-top:16px;
  padding-left:14px;
  border-left:2px solid rgba(53,230,255,.4);
  font-size:12.5px;
  line-height:1.75;
  color:var(--c-steel);
}

.footer-bottom{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:14px;
  margin-top:clamp(30px,4.5vw,52px);
  padding-top:22px;
  border-top:1px solid var(--c-line-soft);
  font-size:12.5px;
  color:var(--c-steel);
}

.footer-legal{
  display:flex;
  flex-wrap:wrap;
  gap:6px 18px;
}

.footer-legal__copy{font-family:var(--font-mono);letter-spacing:.04em;}

.footer-legal__links{
  display:flex;
  flex-wrap:wrap;
  gap:14px;
}

.footer-legal__links a{
  padding:2px 0;
  border-bottom:1px solid transparent;
  transition:color .2s var(--ease),border-color .2s var(--ease);
}

.footer-legal__links a:hover{
  color:var(--c-cyan-soft);
  border-color:rgba(53,230,255,.5);
}

/* ---------- 15. 章节指示器（页面可选组件） ---------- */
.chapter-meter{
  position:fixed;
  right:20px;
  bottom:20px;
  z-index:110;
  display:inline-flex;
  align-items:center;
  gap:10px;
  padding:8px 16px;
  border-radius:var(--radius-pill);
  border:1px solid rgba(53,230,255,.26);
  background:rgba(4,23,38,.88);
  -webkit-backdrop-filter:blur(10px);
  backdrop-filter:blur(10px);
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.14em;
  color:var(--c-cyan-soft);
}

.chapter-meter[hidden]{display:none;}

.chapter-meter__num{color:var(--c-coral);}

/* ---------- 16. 进入动效 ---------- */
[data-reveal]{
  opacity:0;
  transform:translateY(18px);
  transition:opacity .5s var(--ease),transform .5s var(--ease);
}

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

/* ---------- 17. 响应式 ---------- */
@media (max-width:1040px){
  .nav-toggle{display:inline-flex;}

  .site-nav{
    position:fixed;
    top:0;
    right:0;
    bottom:0;
    width:min(348px,88vw);
    margin:0;
    padding:100px 22px 32px;
    flex-direction:column;
    align-items:stretch;
    gap:10px;
    overflow-y:auto;
    z-index:130;
    border-left:1px solid rgba(53,230,255,.22);
    background:linear-gradient(180deg,#06202f 0%,#020D16 100%);
    box-shadow:-34px 0 70px -46px #000;
    transform:translateX(104%);
    visibility:hidden;
    transition:transform .3s var(--ease),visibility .3s var(--ease);
  }

  .site-nav[data-open]{
    transform:none;
    visibility:visible;
  }

  .site-nav__list{
    flex-direction:column;
    align-items:stretch;
    gap:4px;
  }

  .site-nav__link{
    display:block;
    padding:14px 16px;
    border-radius:16px;
    border-color:rgba(53,230,255,.12);
    background:rgba(53,230,255,.04);
    font-size:16px;
  }

  .site-nav__link[aria-current="page"]{
    border-color:rgba(168,246,255,.6);
  }

  .site-nav__cta{
    margin:10px 0 0;
    font-size:14px;
    padding:14px 20px;
  }

  .header-shell{gap:12px;}

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

@media (max-width:900px){
  .grid--2,
  .grid--3,
  .grid--split,
  .grid--aside{grid-template-columns:1fr;}

  .grid--3{grid-template-columns:repeat(2,minmax(0,1fr));}
}

@media (max-width:720px){
  :root{--radius-l:22px;}

  .header-shell{padding:7px 8px 7px 14px;}

  .brand__tag{display:none;}

  .brand__name{font-size:16px;letter-spacing:.06em;}

  .brand__mark{width:32px;height:32px;border-radius:11px;}

  .prose{font-size:16px;}

  .grid--3{grid-template-columns:1fr;}

  .footer-top{grid-template-columns:1fr;}

  .footer-bottom{flex-direction:column;align-items:flex-start;}

  .figure__media{aspect-ratio:4 / 3;}

  .figure--wide .figure__media{aspect-ratio:16 / 9;}

  .chapter-meter{right:12px;bottom:12px;padding:7px 13px;}
}

@media (max-width:420px){
  .nav-toggle__label{display:none;}

  .footer-cols{grid-template-columns:1fr;}
}

@media (prefers-reduced-motion:reduce){
  *,
  *::before,
  *::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }

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