/* =========================================================
   天辰主页 · 共享样式 /assets/site.css
   构图：左侧品牌轨道 + 右侧正文（侧边导览式，桌面折叠 88px / 展开 240px）
   ========================================================= */

/* ---------- 1 变量 ---------- */
:root{
  --deep:#0B2A4A;
  --midnight:#071A2E;
  --coral:#FF6B4A;
  --coral-soft:#FFA184;
  --teal:#17C3B2;
  --gold:#D9A441;
  --pearl:#F7F5F0;
  --sand:#EDE6DA;
  --mist:#6B8299;
  --ink:#10202E;

  --rail-w:240px;
  --header-h:64px;

  --radius-xl:32px;
  --radius-lg:28px;
  --radius-md:20px;
  --radius-sm:14px;
  --pill:999px;

  --font-head:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --font-body:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;

  --shadow-card:0 22px 48px -30px rgba(7,26,46,.5);
  --shadow-float:0 30px 70px -34px rgba(7,26,46,.58);
  --line-soft:rgba(11,42,74,.12);
  --line-dark:rgba(247,245,240,.14);
}

/* ---------- 2 Reset & 基础排版 ---------- */
*,
*::before,
*::after{box-sizing:border-box}

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

body{
  margin:0;
  padding-left:0;
  background:var(--pearl);
  color:var(--ink);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.85;
  letter-spacing:.01em;
  overflow-x:hidden;
  transition:padding-left .32s ease;
}

h1,h2,h3,h4,h5,h6{
  font-family:var(--font-head);
  font-weight:900;
  letter-spacing:.02em;
  line-height:1.32;
  color:var(--deep);
  margin:0 0 .5em;
}

h1{font-size:clamp(30px,4.4vw,44px)}
h2{font-size:clamp(25px,3.4vw,34px)}
h3{font-size:clamp(20px,2.4vw,25px)}
h4{font-size:19px}

p{margin:0 0 20px}
p:last-child{margin-bottom:0}

a{color:var(--deep);text-decoration-color:rgba(255,107,74,.6);text-underline-offset:3px}
a:hover{color:var(--coral)}

ul,ol{margin:0 0 20px;padding-left:1.25em}
img{max-width:100%;height:auto;display:block}
button{font-family:inherit}
hr{border:0;border-top:1px solid var(--line-soft);margin:32px 0}

::selection{background:var(--coral);color:#fff}

.mono,.metric,.phase,.breadcrumbs,.nav-link__index,.eyebrow,.footer-col__title,.footer-contact__label,.footer-contact__value--mono,.media__caption{
  font-family:var(--font-mono);
  font-variant-numeric:tabular-nums;
}

.lede{font-size:clamp(17px,1.8vw,19px);line-height:1.9;color:#31465a;max-width:64ch}
.muted{color:var(--mist)}
.divider{height:1px;background:var(--line-soft);border:0;margin:clamp(28px,4vw,48px) 0}

/* ---------- 3 可访问性 ---------- */
:focus-visible{
  outline:3px solid var(--teal);
  outline-offset:3px;
  border-radius:8px;
}
.section--dark :focus-visible,
.section--deep :focus-visible,
.site-header :focus-visible,
.site-footer :focus-visible{
  outline-color:var(--coral-soft);
}

.skip-link{
  position:fixed;
  top:12px;
  left:12px;
  z-index:200;
  transform:translateY(-180%);
  background:var(--coral);
  color:#0B2A4A;
  font-weight:700;
  font-size:15px;
  padding:11px 20px;
  border-radius:var(--pill);
  text-decoration:none;
  box-shadow:var(--shadow-float);
  transition:transform .2s ease;
}
.skip-link:focus{transform:none;color:#0B2A4A}

/* ---------- 4 头部 / 品牌轨道 ---------- */
.site-header{
  position:sticky;
  top:0;
  z-index:80;
  background:var(--deep);
  color:var(--pearl);
  border-bottom:1px solid rgba(23,195,178,.24);
}

.site-header::before{
  content:"";
  position:fixed;
  inset:var(--header-h) 0 0 0;
  background:rgba(7,26,46,.62);
  z-index:-1;
  opacity:0;
  pointer-events:none;
  transition:opacity .25s ease;
}
.site-header[data-open]::before{opacity:1;pointer-events:auto}

.rail-top{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:12px;
  min-height:var(--header-h);
  padding:8px 16px;
}

.brand-mark{
  display:flex;
  align-items:center;
  gap:12px;
  text-decoration:none;
  color:var(--pearl);
  min-width:0;
}
.brand-mark:hover{color:var(--pearl)}

.brand-mark__glyph{
  flex:0 0 auto;
  width:40px;
  height:40px;
  display:grid;
  place-items:center;
  border-radius:var(--radius-sm);
  background:linear-gradient(140deg,var(--coral),var(--gold));
  color:var(--midnight);
  font-family:var(--font-head);
  font-weight:900;
  font-size:20px;
  letter-spacing:.02em;
}

.brand-mark__text{display:flex;flex-direction:column;min-width:0}
.brand-mark__name{
  font-family:var(--font-head);
  font-weight:900;
  font-size:18px;
  letter-spacing:.06em;
  line-height:1.3;
  white-space:nowrap;
}
.brand-mark__tag{
  font-size:12px;
  letter-spacing:.1em;
  color:rgba(247,245,240,.66);
  line-height:1.5;
  white-space:nowrap;
}

.rail-toggle{
  flex:0 0 auto;
  display:inline-flex;
  flex-direction:column;
  align-items:center;
  gap:5px;
  padding:8px 10px;
  background:rgba(23,195,178,.12);
  border:1px solid rgba(23,195,178,.32);
  border-radius:var(--radius-sm);
  color:var(--pearl);
  font-size:11px;
  letter-spacing:.16em;
  cursor:pointer;
  transition:background-color .2s ease,border-color .2s ease,transform .2s ease;
}
.rail-toggle:hover{background:rgba(23,195,178,.26);border-color:var(--teal)}
.rail-toggle__icon{display:flex;flex-direction:column;gap:4px;width:20px}
.rail-toggle__icon span{display:block;height:2px;border-radius:2px;background:var(--teal)}
.rail-toggle__icon span:nth-child(2){width:72%}
.rail-toggle__icon span:nth-child(3){width:44%}
.rail-toggle__text{line-height:1}

.rail-note{display:none}

/* 移动端抽屉 */
.site-nav{
  position:fixed;
  top:var(--header-h);
  left:0;
  bottom:0;
  width:min(86vw,340px);
  display:flex;
  flex-direction:column;
  gap:18px;
  padding:22px 16px 32px;
  background:var(--midnight);
  border-right:1px solid rgba(23,195,178,.22);
  overflow-y:auto;
  transform:translateX(-104%);
  transition:transform .34s cubic-bezier(.22,.72,.2,1);
}
.site-header[data-open] .site-nav{transform:none}

.nav-list{
  list-style:none;
  margin:0;
  padding:0;
  display:flex;
  flex-direction:column;
  gap:6px;
}

.nav-link{
  display:flex;
  align-items:center;
  gap:12px;
  padding:13px 16px;
  border-radius:var(--pill);
  color:rgba(247,245,240,.84);
  text-decoration:none;
  font-weight:600;
  font-size:16px;
  letter-spacing:.02em;
  transition:background-color .2s ease,color .2s ease,transform .2s ease;
}
.nav-link__index{
  font-size:12px;
  letter-spacing:.08em;
  color:var(--teal);
  opacity:.85;
}
.nav-link__label{white-space:nowrap}
.nav-link:hover{background:rgba(23,195,178,.14);color:#fff;transform:translateX(2px)}
.nav-link[aria-current="page"]{
  background:var(--coral);
  color:#0B2A4A;
  font-weight:700;
}
.nav-link[aria-current="page"] .nav-link__index{color:#0B2A4A;opacity:.72}

.rail-actions{
  display:flex;
  flex-direction:column;
  gap:10px;
  margin-top:auto;
  padding-top:18px;
  border-top:1px solid var(--line-dark);
}
.rail-cta{width:100%}

/* 进度光轨 */
.rail-progress{
  position:absolute;
  left:0;
  right:0;
  bottom:0;
  height:3px;
  background:rgba(247,245,240,.1);
  overflow:hidden;
}
.rail-progress__bar{
  display:block;
  height:100%;
  width:100%;
  transform:scaleX(0);
  transform-origin:left center;
  background:linear-gradient(90deg,var(--coral),var(--gold),var(--teal));
  transition:transform .12s linear;
}

/* ---------- 5 按钮 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:9px;
  padding:13px 22px;
  border-radius:var(--pill);
  border:1px solid transparent;
  font-size:15px;
  font-weight:700;
  letter-spacing:.04em;
  line-height:1.4;
  text-decoration:none;
  cursor:pointer;
  transition:background-color .2s ease,color .2s ease,border-color .2s ease,transform .2s ease,box-shadow .2s ease;
}
.btn--primary{background:var(--coral);color:#0B2A4A;box-shadow:0 14px 30px -18px rgba(255,107,74,.9)}
.btn--primary:hover{background:var(--coral-soft);color:#0B2A4A;transform:translateY(-2px)}
.btn--ghost{background:transparent;border-color:rgba(247,245,240,.34);color:var(--pearl)}
.btn--ghost:hover{border-color:var(--teal);color:var(--teal);transform:translateY(-2px)}
.btn--dark{background:var(--deep);color:var(--pearl)}
.btn--dark:hover{background:#143b63;color:var(--pearl);transform:translateY(-2px)}
.btn--line{background:transparent;border-color:rgba(11,42,74,.28);color:var(--deep)}
.btn--line:hover{border-color:var(--coral);color:var(--coral)}
.btn__glyph{display:none}

/* ---------- 6 容器 / 分区 / 网格 ---------- */
.container{width:min(1180px,100% - 40px);margin-inline:auto}

.section{padding:clamp(48px,7vw,96px) 0}
.section--tight{padding:clamp(30px,4vw,54px) 0}
.section--sand{background:var(--sand);color:var(--ink)}
.section--dark{background:var(--deep);color:rgba(247,245,240,.9)}
.section--deep{background:var(--midnight);color:rgba(247,245,240,.9)}

.section--dark h1,.section--dark h2,.section--dark h3,
.section--deep h1,.section--deep h2,.section--deep h3{color:var(--pearl)}
.section--dark a,.section--deep a{color:var(--pearl)}
.section--dark a:hover,.section--deep a:hover{color:var(--coral-soft)}
.section--dark .muted,.section--deep .muted{color:rgba(247,245,240,.65)}

.grid{
  display:grid;
  grid-template-columns:repeat(12,minmax(0,1fr));
  gap:clamp(16px,2.2vw,28px);
}
.col-4,.col-6,.col-8{grid-column:span 12}

/* ---------- 7 章节头 / 展览标签 ---------- */
.section-head{max-width:66ch;margin-bottom:clamp(24px,3vw,40px)}
.section-head h2{margin:14px 0 10px}
.section-head p{color:#3b5063}
.section--dark .section-head p,.section--deep .section-head p{color:rgba(247,245,240,.78)}

.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:9px;
  padding:6px 14px;
  border-radius:var(--pill);
  background:var(--sand);
  color:var(--deep);
  font-size:12.5px;
  font-weight:700;
  letter-spacing:.16em;
  text-transform:uppercase;
}
.eyebrow--on-dark{background:rgba(23,195,178,.16);color:var(--teal)}

.phase{
  display:inline-block;
  font-size:13px;
  font-weight:700;
  letter-spacing:.2em;
  color:var(--coral);
}
.section--dark .phase,.section--deep .phase{color:var(--coral-soft)}

/* ---------- 8 卡片 / 说明牌 / 数据 ---------- */
.card{
  position:relative;
  background:#fff;
  border:1px solid var(--line-soft);
  border-radius:var(--radius-lg);
  padding:clamp(20px,2.4vw,32px);
  box-shadow:var(--shadow-card);
}
.card h3{margin-bottom:10px}
.card--sand{background:var(--sand);box-shadow:none;border-color:rgba(11,42,74,.08)}
.card--dark{background:var(--deep);border-color:rgba(23,195,178,.22);color:rgba(247,245,240,.9);box-shadow:var(--shadow-float)}
.card--dark h3{color:var(--pearl)}

.note{
  background:var(--sand);
  border-left:4px solid var(--teal);
  border-radius:var(--radius-md);
  padding:18px 20px;
  font-size:15.5px;
  line-height:1.8;
  color:#3f5468;
}
.note strong{color:var(--deep)}

.metric{
  display:block;
  font-size:clamp(24px,3vw,34px);
  font-weight:700;
  letter-spacing:-.01em;
  color:var(--deep);
  line-height:1.25;
}
.metric--gold{color:var(--gold)}
.section--dark .metric,.section--deep .metric{color:var(--pearl)}
.section--dark .metric--gold,.section--deep .metric--gold{color:var(--gold)}

/* ---------- 9 延伸入口 ---------- */
.extend{
  display:flex;
  flex-wrap:wrap;
  gap:10px;
  margin:22px 0 0;
  padding:0;
  list-style:none;
}
.extend a{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:8px 16px;
  border:1px dashed rgba(11,42,74,.26);
  border-radius:var(--pill);
  font-size:14px;
  font-weight:600;
  text-decoration:none;
  color:var(--deep);
  transition:border-color .2s ease,color .2s ease,background-color .2s ease;
}
.extend a:hover{border-style:solid;border-color:var(--coral);color:var(--coral);background:rgba(255,107,74,.07)}
.section--dark .extend a,.section--deep .extend a{border-color:rgba(247,245,240,.3);color:var(--pearl)}
.section--dark .extend a:hover,.section--deep .extend a:hover{border-color:var(--teal);color:var(--teal);background:rgba(23,195,178,.1)}

/* ---------- 10 面包屑 ---------- */
.breadcrumbs{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  margin:0 0 20px;
  padding:0;
  list-style:none;
  font-size:13px;
  letter-spacing:.06em;
  color:var(--mist);
}
.breadcrumbs li{display:flex;align-items:center;gap:8px}
.breadcrumbs li::after{content:"/";color:rgba(107,130,153,.55)}
.breadcrumbs li:last-child::after{content:""}
.breadcrumbs a{color:var(--mist);text-decoration:none}
.breadcrumbs a:hover{color:var(--coral)}
.breadcrumbs [aria-current="page"]{color:var(--deep);font-weight:700}
.section--dark .breadcrumbs,.section--deep .breadcrumbs{color:rgba(247,245,240,.6)}
.section--dark .breadcrumbs a,.section--deep .breadcrumbs a{color:rgba(247,245,240,.7)}
.section--dark .breadcrumbs [aria-current="page"],.section--deep .breadcrumbs [aria-current="page"]{color:var(--pearl)}

/* ---------- 11 图片容器 ---------- */
.media{
  position:relative;
  display:block;
  overflow:hidden;
  border-radius:var(--radius-lg);
  background:linear-gradient(140deg,#0B2A4A 0%,#123a5f 55%,#071A2E 100%);
  aspect-ratio:16 / 9;
  isolation:isolate;
}
.media--wide{aspect-ratio:21 / 9}
.media--square{aspect-ratio:1 / 1}
.media--portrait{aspect-ratio:3 / 4}
.media img{
  width:100%;
  height:100%;
  object-fit:cover;
  display:block;
}
.media--placeholder::after{
  content:"";
  position:absolute;
  inset:0;
  background:
    radial-gradient(circle at 82% 18%,rgba(23,195,178,.35),transparent 42%),
    repeating-linear-gradient(135deg,rgba(23,195,178,.14) 0 2px,transparent 2px 16px);
}
.media__caption{
  position:absolute;
  left:16px;
  bottom:16px;
  z-index:2;
  margin:0;
  padding:8px 14px;
  border-radius:var(--pill);
  background:rgba(7,26,46,.74);
  color:var(--pearl);
  font-size:12.5px;
  letter-spacing:.06em;
}
.media-stack{display:grid;gap:clamp(14px,2vw,22px)}

/* ---------- 12 标签页 / 手风琴 ---------- */
.tablist{
  display:inline-flex;
  flex-wrap:wrap;
  gap:6px;
  padding:6px;
  margin:0 0 22px;
  background:var(--sand);
  border-radius:var(--pill);
}
.tab{
  border:0;
  background:transparent;
  color:#4b6073;
  font-size:15px;
  font-weight:700;
  letter-spacing:.02em;
  padding:10px 20px;
  border-radius:var(--pill);
  cursor:pointer;
  transition:background-color .2s ease,color .2s ease;
}
.tab:hover{color:var(--deep);background:rgba(11,42,74,.07)}
.tab[aria-selected="true"]{background:var(--deep);color:var(--pearl)}
.tabpanel:focus-visible{outline-offset:6px}
.tabpanel[hidden]{display:none}
.tabpanel > :first-child{margin-top:0}

.accordion{border-top:1px solid var(--line-soft)}
.accordion__item{border-bottom:1px solid var(--line-soft)}
.accordion__trigger{
  width:100%;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:16px;
  padding:18px 4px;
  background:none;
  border:0;
  text-align:left;
  font-size:17px;
  font-weight:700;
  color:var(--deep);
  cursor:pointer;
}
.accordion__trigger::after{
  content:"+";
  flex:0 0 auto;
  font-family:var(--font-mono);
  font-size:20px;
  color:var(--coral);
  line-height:1;
}
.accordion__trigger[aria-expanded="true"]::after{content:"–"}
.accordion__panel{padding:0 4px 20px;font-size:16px;color:#3f5468}
.accordion__panel[hidden]{display:none}

/* ---------- 13 进入动效 ---------- */
.reveal{
  opacity:0;
  transform:translateY(14px);
  transition:opacity .6s ease,transform .6s ease;
}
.reveal.is-visible{opacity:1;transform:none}

/* ---------- 14 页脚 ---------- */
.site-footer{
  position:relative;
  margin-top:clamp(48px,7vw,96px);
  padding:clamp(40px,5vw,76px) 0 26px;
  background:var(--midnight);
  color:rgba(247,245,240,.86);
  border-radius:var(--radius-xl) var(--radius-xl) 0 0;
  overflow:hidden;
}
.site-footer::before{
  content:"";
  position:absolute;
  inset:0 0 auto 0;
  height:4px;
  background:linear-gradient(90deg,var(--teal),var(--coral),var(--gold));
}
.site-footer h2,.site-footer h3{color:var(--pearl)}

.footer-main{
  display:grid;
  grid-template-columns:1fr;
  gap:clamp(28px,4vw,56px);
}
.footer-brand{max-width:44ch}
.footer-brand__name{
  display:flex;
  align-items:center;
  gap:12px;
  margin:0 0 14px;
  font-family:var(--font-head);
  font-weight:900;
  font-size:22px;
  letter-spacing:.06em;
  color:var(--pearl);
}
.footer-brand__glyph{
  width:38px;
  height:38px;
  display:grid;
  place-items:center;
  border-radius:var(--radius-sm);
  background:linear-gradient(140deg,var(--coral),var(--gold));
  color:var(--midnight);
  font-size:19px;
}
.footer-slogan{
  font-size:17px;
  line-height:1.85;
  color:rgba(247,245,240,.82);
  margin:0 0 22px;
}
.footer-cta{width:auto}

.footer-cols{
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:26px;
}
.footer-col__title{
  margin:0 0 14px;
  font-size:12.5px;
  font-weight:700;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--teal);
}
.footer-links{list-style:none;margin:0;padding:0;display:flex;flex-direction:column;gap:10px}
.footer-links a{
  font-size:15.5px;
  color:rgba(247,245,240,.84);
  text-decoration:none;
  transition:color .2s ease;
}
.footer-links a:hover{color:var(--coral-soft);text-decoration:underline;text-underline-offset:3px}

.footer-contact{
  display:grid;
  grid-template-columns:1fr;
  gap:16px;
  margin:clamp(30px,4vw,50px) 0 0;
  padding-top:26px;
  border-top:1px solid var(--line-dark);
}
.footer-contact__item{display:flex;flex-direction:column;gap:2px;margin:0}
.footer-contact__label{
  font-size:11.5px;
  letter-spacing:.16em;
  text-transform:uppercase;
  color:var(--gold);
}
.footer-contact__value{margin:0;font-size:15.5px;line-height:1.7;color:rgba(247,245,240,.9);word-break:break-word}
.footer-contact__value--mono{letter-spacing:.01em}

.footer-bottom{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:10px;
  margin-top:26px;
  padding-top:20px;
  border-top:1px solid var(--line-dark);
  font-size:13.5px;
  color:rgba(247,245,240,.6);
}
.footer-bottom p{margin:0}
.footer-legal{letter-spacing:.04em}

/* ---------- 15 平板与桌面：侧边导览式布局 ---------- */
@media (min-width:600px){
  .footer-cols{grid-template-columns:repeat(3,minmax(0,1fr))}
  .footer-contact{grid-template-columns:repeat(2,minmax(0,1fr))}
}

@media (min-width:900px){
  .col-8{grid-column:span 8}
  .col-4{grid-column:span 4}
  .col-6{grid-column:span 6}
  .footer-main{grid-template-columns:1.05fr 1.95fr;align-items:start}
  .footer-contact{grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}
}

@media (min-width:1024px){
  body{padding-left:var(--rail-w)}

  .skip-link{left:calc(var(--rail-w) + 16px)}

  .site-header{
    position:fixed;
    inset:0 auto 0 0;
    width:var(--rail-w);
    display:flex;
    flex-direction:column;
    padding:26px 0 0;
    border-bottom:0;
    border-right:1px solid rgba(23,195,178,.24);
    background:linear-gradient(180deg,var(--deep) 0%,#0a2643 58%,var(--midnight) 100%);
    transition:width .32s ease;
  }
  .site-header::before{display:none}

  .rail-top{
    min-height:0;
    padding:0 18px;
    align-items:flex-start;
    justify-content:space-between;
    gap:10px;
  }
  .brand-mark__name{font-size:18px}
  .rail-toggle{flex-direction:row;gap:8px;padding:9px 11px;border-radius:var(--radius-sm)}
  .rail-toggle__icon{width:16px}
  .rail-toggle__text{font-size:11px}

  .rail-note{
    display:block;
    margin:14px 20px 0;
    padding:9px 12px;
    font-size:12.5px;
    line-height:1.7;
    color:rgba(247,245,240,.66);
    background:rgba(23,195,178,.1);
    border-radius:var(--radius-sm);
    border-left:3px solid var(--teal);
  }

  .site-nav{
    position:static;
    width:auto;
    transform:none;
    background:transparent;
    border-right:0;
    padding:24px 14px 0;
    flex:1 1 auto;
    gap:0;
    overflow-y:auto;
    transition:none;
  }
  .nav-list{gap:4px}
  .nav-link{font-size:15.5px;padding:12px 14px}
  .rail-actions{padding:18px 0 24px}

  /* 折叠态：88px 编号航道 */
  html[data-rail="collapsed"]{--rail-w:88px}
  html[data-rail="collapsed"] .site-header{background:linear-gradient(180deg,var(--deep),var(--midnight))}
  html[data-rail="collapsed"] .rail-top{
    flex-direction:column;
    align-items:center;
    justify-content:flex-start;
    gap:16px;
    padding:0 8px;
  }
  html[data-rail="collapsed"] .brand-mark__text{display:none}
  html[data-rail="collapsed"] .brand-mark{gap:0}
  html[data-rail="collapsed"] .rail-toggle{flex-direction:column;gap:5px;padding:8px 9px}
  html[data-rail="collapsed"] .rail-toggle__text{display:none}
  html[data-rail="collapsed"] .rail-note{display:none}
  html[data-rail="collapsed"] .site-nav{padding:22px 10px 0}
  html[data-rail="collapsed"] .nav-link{justify-content:center;padding:13px 6px;gap:0}
  html[data-rail="collapsed"] .nav-link__label{display:none}
  html[data-rail="collapsed"] .nav-link__index{font-size:13px;letter-spacing:.06em}
  html[data-rail="collapsed"] .rail-actions{padding:16px 4px 24px;align-items:center}
  html[data-rail="collapsed"] .rail-cta{
    width:48px;
    height:48px;
    padding:0;
    border-radius:50%;
    font-size:17px;
    letter-spacing:0;
  }
  html[data-rail="collapsed"] .site-header .btn__glyph{display:inline-block}
  html[data-rail="collapsed"] .site-header .btn__text{display:none}
}

/* ---------- 16 动效偏好 ---------- */
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto}
  *,
  *::before,
  *::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  .reveal{opacity:1;transform:none}
  .site-nav{transition:none}
  .rail-progress__bar{transition:none}
}