/* ===== 01 变量 ===== */
:root{
  --ink-950:#071521;
  --ink-900:#0C2233;
  --ink-700:#1B4058;
  --mist-200:#C9D8E2;
  --paper:#F7F4EC;
  --copper:#B98245;
  --copper-light:#E9C9A1;
  --coral:#F05A3C;
  --celadon:#6FA594;
  --ink-text:#13232F;
  --slate:#5C7385;

  --font-display:"Noto Serif SC","Songti SC","STSong",serif;
  --font-body:"Inter","PingFang SC","Noto Sans SC",sans-serif;
  --font-mono:"IBM Plex Mono","JetBrains Mono",monospace;

  --rail-w:268px;
  --gutter:clamp(18px,4vw,56px);
  --radius-xl:32px;
  --radius-lg:24px;
  --radius-md:16px;
  --radius-pill:999px;
  --dur:200ms;
  --ease:cubic-bezier(.2,.7,.2,1);
  --hair:1px solid rgba(185,130,69,.28);
  --hair-soft:1px solid rgba(201,216,226,.14);
  --shadow-soft:0 18px 40px -28px rgba(7,21,33,.65);
}

/* ===== 02 重置与基础排版 ===== */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;
  background:var(--paper);
  color:var(--ink-text);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.85;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
img,svg,video{display:block;max-width:100%}
h1,h2,h3,h4,h5,p,ul,ol,figure,blockquote,dl,dd{margin:0}
ul,ol{padding:0;list-style:none}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit;color:inherit}
table{border-collapse:collapse;width:100%}
::selection{background:var(--copper);color:var(--ink-950)}
:focus-visible{outline:2px solid var(--coral);outline-offset:2px}
#main-content{display:block;scroll-margin-top:92px}

/* ===== 03 跳转链接 ===== */
.skip-link{
  position:fixed;
  top:10px;
  left:10px;
  z-index:200;
  transform:translateY(-220%);
  display:inline-flex;
  align-items:center;
  padding:.6rem 1.1rem;
  border-radius:var(--radius-pill);
  background:var(--coral);
  color:var(--ink-950);
  font-size:14px;
  font-weight:600;
  transition:transform var(--dur) var(--ease);
}
.skip-link:focus,
.skip-link:focus-visible{transform:translateY(0);outline:2px solid var(--paper);outline-offset:2px}

/* ===== 04 页头：移动端顶部胶囊条 ===== */
.site-header{
  position:sticky;
  top:0;
  z-index:80;
  background:var(--ink-950);
  color:var(--paper);
  border-bottom:var(--hair);
}
.site-header__inner{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:12px;
  padding:12px clamp(16px,4vw,28px);
}
.brand{min-width:0}
.brand__link{display:flex;align-items:center;gap:12px;min-width:0}
.brand__mark{
  display:grid;
  place-items:center;
  flex:0 0 auto;
  width:42px;
  height:42px;
  border-radius:14px;
  background:linear-gradient(150deg,var(--copper-light),var(--copper) 55%,#8a5f31);
  color:var(--ink-950);
  font-family:var(--font-mono);
  font-size:14px;
  font-weight:500;
  letter-spacing:.08em;
  box-shadow:inset 0 0 0 1px rgba(7,21,33,.28);
}
.brand__text{display:flex;flex-direction:column;min-width:0}
.brand__name{
  font-family:var(--font-display);
  font-size:18px;
  font-weight:700;
  line-height:1.3;
  letter-spacing:.02em;
  color:var(--paper);
}
.brand__tagline{
  font-family:var(--font-mono);
  font-size:10px;
  line-height:1.5;
  letter-spacing:.1em;
  color:var(--copper-light);
  opacity:.9;
}
.nav-toggle{
  display:inline-flex;
  align-items:center;
  gap:9px;
  padding:9px 16px;
  border-radius:var(--radius-pill);
  border:1px solid rgba(185,130,69,.5);
  background:rgba(201,216,226,.06);
  color:var(--paper);
  font-size:13px;
  font-weight:600;
  letter-spacing:.04em;
  cursor:pointer;
  transition:background-color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.nav-toggle:hover{background:rgba(185,130,69,.22);border-color:var(--copper)}
.nav-toggle__bars{display:inline-flex;flex-direction:column;justify-content:center;gap:4px;width:16px;height:12px}
.nav-toggle__bars span{display:block;height:1.5px;width:100%;border-radius:2px;background:var(--copper-light);transition:transform var(--dur) var(--ease)}
.site-header[data-open] .nav-toggle__bars span:first-child{transform:translateY(2.75px) rotate(45deg)}
.site-header[data-open] .nav-toggle__bars span:last-child{transform:translateY(-2.75px) rotate(-45deg)}
.nav-toggle__label{white-space:nowrap}

/* 移动端导航面板 */
.site-nav{
  order:3;
  flex:1 0 100%;
  display:flex;
  flex-direction:column;
  width:100%;
  max-height:0;
  padding:0;
  overflow:hidden;
  opacity:0;
  visibility:hidden;
  transition:max-height 240ms var(--ease),opacity 180ms var(--ease),visibility 0s linear 240ms;
}
.site-header[data-open] .site-nav{
  max-height:76vh;
  padding-top:16px;
  padding-bottom:20px;
  overflow-y:auto;
  opacity:1;
  visibility:visible;
  transition:max-height 240ms var(--ease),opacity 180ms var(--ease),visibility 0s linear 0s;
}
.site-nav__label{
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.22em;
  text-transform:uppercase;
  color:var(--copper);
  padding-bottom:8px;
  border-bottom:var(--hair-soft);
}
.site-nav__list{
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:4px;
  padding-top:10px;
}
.site-nav__item{min-width:0}
.site-nav__link{
  display:flex;
  align-items:baseline;
  gap:10px;
  padding:10px 12px;
  border-radius:14px;
  border:1px solid transparent;
  color:var(--mist-200);
  font-size:15px;
  font-weight:500;
  line-height:1.5;
  transition:background-color var(--dur) var(--ease),color var(--dur) var(--ease),border-color var(--dur) var(--ease),box-shadow var(--dur) var(--ease);
}
.site-nav__link:hover{
  background:rgba(201,216,226,.08);
  border-color:rgba(185,130,69,.4);
  color:var(--paper);
}
.site-nav__link:focus-visible{outline:2px solid var(--coral);outline-offset:2px}
.site-nav__link[aria-current="page"]{
  background:rgba(185,130,69,.16);
  border-color:rgba(185,130,69,.58);
  color:var(--paper);
  box-shadow:inset 3px 0 0 0 var(--coral);
}
.site-nav__index{
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.14em;
  color:var(--copper);
  flex:0 0 auto;
}
.site-nav__link[aria-current="page"] .site-nav__index{color:var(--coral)}
.site-nav__text{min-width:0}

/* 导航内加重卡：第一次进站板块指南 */
.rail-guide{
  position:relative;
  margin-top:18px;
  padding:16px 16px 18px;
  border-radius:20px;
  border:1px solid rgba(185,130,69,.45);
  background:linear-gradient(158deg,rgba(185,130,69,.22),rgba(12,34,51,.72));
  overflow:hidden;
}
.rail-guide::before{
  content:"";
  position:absolute;
  top:0;
  left:18px;
  width:46px;
  height:2px;
  background:var(--coral);
}
.rail-guide__label{
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--celadon);
  margin-bottom:8px;
}
.rail-guide__title{
  font-family:var(--font-display);
  font-size:19px;
  font-weight:700;
  line-height:1.4;
  letter-spacing:.01em;
  color:var(--paper);
  margin-bottom:8px;
}
.rail-guide__text{
  font-size:13px;
  line-height:1.7;
  color:var(--mist-200);
  margin-bottom:12px;
}
.rail-guide__link{
  display:inline-flex;
  align-items:center;
  gap:6px;
  font-size:13px;
  font-weight:600;
  color:var(--copper-light);
  border-bottom:1px solid rgba(233,201,161,.45);
  padding-bottom:2px;
  transition:color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.rail-guide__link:hover{color:var(--paper);border-bottom-color:var(--coral)}
.rail-foot{margin-top:18px}
.rail-cta{width:100%}
.rail-meta{
  margin-top:12px;
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.12em;
  line-height:1.7;
  color:rgba(201,216,226,.62);
}

/* 滚动进度 */
.scroll-progress{
  position:fixed;
  top:0;
  left:0;
  right:0;
  height:3px;
  z-index:120;
  pointer-events:none;
  background:rgba(7,21,33,.16);
}
.scroll-progress__bar{
  display:block;
  height:100%;
  width:0;
  background:linear-gradient(90deg,var(--copper),var(--coral));
  transition:width 120ms linear;
}

/* ===== 05 页脚 ===== */
.site-footer{
  background:var(--ink-950);
  color:var(--mist-200);
  border-top:1px solid rgba(185,130,69,.3);
}
.footer-guide{
  background:var(--ink-900);
  border-bottom:1px solid rgba(185,130,69,.22);
}
.footer-guide__inner{
  display:grid;
  gap:16px;
  align-items:center;
  max-width:1180px;
  margin-inline:auto;
  padding:clamp(26px,4vw,42px) var(--gutter);
}
.footer-guide__head{display:grid;gap:6px}
.footer-guide__label{
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--celadon);
}
.footer-guide__title{
  font-family:var(--font-display);
  font-size:clamp(21px,2.6vw,28px);
  font-weight:700;
  line-height:1.35;
  letter-spacing:.01em;
  color:var(--paper);
}
.footer-guide__text{
  font-size:14px;
  line-height:1.8;
  color:var(--mist-200);
  max-width:46ch;
}
.footer-guide__link{justify-self:start;white-space:nowrap}
.footer-body{
  display:grid;
  gap:clamp(24px,4vw,40px);
  padding-block:clamp(32px,5vw,52px);
}
.footer-brand{display:grid;gap:10px;justify-items:start}
.footer-brand__mark{
  display:grid;
  place-items:center;
  width:40px;
  height:40px;
  border-radius:13px;
  background:linear-gradient(150deg,var(--copper-light),var(--copper) 55%,#8a5f31);
  color:var(--ink-950);
  font-family:var(--font-mono);
  font-size:13px;
  font-weight:500;
  letter-spacing:.08em;
}
.footer-brand__name{
  font-family:var(--font-display);
  font-size:19px;
  font-weight:700;
  letter-spacing:.02em;
  color:var(--paper);
}
.footer-brand__summary{
  font-size:13px;
  line-height:1.75;
  color:rgba(201,216,226,.75);
  max-width:30ch;
}
.footer-cols{
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:22px;
}
.footer-col__title{
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--copper);
  margin-bottom:10px;
}
.footer-col__list{display:grid;gap:8px}
.footer-link{
  display:inline-block;
  font-size:14px;
  line-height:1.7;
  color:var(--mist-200);
  border-bottom:1px solid transparent;
  transition:color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.footer-link:hover{color:var(--paper);border-bottom-color:var(--coral)}
.footer-link:focus-visible{outline:2px solid var(--coral);outline-offset:2px}
.footer-contact{display:grid;gap:2px}
.contact-line{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  padding-block:3px;
}
.contact-line__key{
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.14em;
  color:var(--copper);
  min-width:2.4em;
}
.contact-line__value{
  font-family:var(--font-mono);
  font-size:12.5px;
  letter-spacing:.03em;
  color:var(--paper);
  word-break:break-all;
}
.contact-line__value--wide{
  font-family:var(--font-body);
  font-size:13px;
  line-height:1.6;
  letter-spacing:.01em;
}
.copy-btn{
  padding:3px 10px;
  border-radius:var(--radius-pill);
  border:1px solid rgba(111,165,148,.55);
  background:rgba(111,165,148,.12);
  color:var(--celadon);
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.12em;
  cursor:pointer;
  transition:background-color var(--dur) var(--ease),color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.copy-btn:hover{background:rgba(111,165,148,.28);color:var(--paper)}
.copy-btn[data-copied="true"]{background:var(--celadon);border-color:var(--celadon);color:var(--ink-950)}
.copy-btn[data-copied="false"]{background:rgba(240,90,60,.22);border-color:var(--coral);color:var(--copper-light)}
.footer-contact__note{
  margin-top:14px;
  max-width:38ch;
  font-size:11.5px;
  line-height:1.8;
  color:rgba(201,216,226,.55);
}
.footer-legal{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:10px 24px;
  padding-block:22px;
  border-top:1px solid rgba(201,216,226,.12);
}
.footer-legal__copy,
.footer-legal__icp{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.1em;
  color:rgba(201,216,226,.6);
}
.footer-legal__links{display:flex;flex-wrap:wrap;gap:8px 18px}
.footer-legal__links .footer-link{font-size:11.5px;color:rgba(201,216,226,.7)}

/* ===== 06 通用布局组件 ===== */
.container{
  width:100%;
  max-width:1180px;
  margin-inline:auto;
  padding-inline:var(--gutter);
}
.container--narrow{max-width:760px}
.section{padding-block:clamp(48px,7vw,96px)}
.section--ink{background:var(--ink-900);color:var(--paper)}
.section--ink .section-head__text,
.section--ink .lead,
.section--ink .card__text,
.section--ink .prose{color:var(--mist-200)}
.section--ink .mono-note{color:rgba(201,216,226,.7)}
.section--ink a{color:var(--copper-light)}
.stack>*+*{margin-top:1.25rem}
.grid{display:grid;gap:clamp(14px,2vw,20px)}
.grid--2{grid-template-columns:repeat(auto-fit,minmax(min(100%,260px),1fr))}
.grid--3{grid-template-columns:repeat(auto-fit,minmax(min(100%,220px),1fr))}
.grid--4{grid-template-columns:repeat(auto-fit,minmax(min(100%,170px),1fr))}

/* ===== 07 文本组件 ===== */
.display{
  font-family:var(--font-display);
  font-weight:900;
  font-size:clamp(40px,7vw,96px);
  line-height:1.02;
  letter-spacing:-.02em;
}
.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:.6em;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--copper);
}
.eyebrow::before{content:"";width:20px;height:1px;background:currentColor}
.lead{
  font-size:clamp(17px,1.6vw,18px);
  line-height:1.85;
  color:var(--slate);
  max-width:68ch;
}
.prose{max-width:68ch;font-size:16px;line-height:1.9}
.prose p+p{margin-top:1.05em}
.prose h2,
.prose h3{margin-top:1.6em;margin-bottom:.5em;font-family:var(--font-display);line-height:1.35}
.prose h2{font-size:clamp(22px,2.4vw,28px)}
.prose h3{font-size:20px}
.prose ul{list-style:disc;padding-left:1.15em;margin-top:.8em;display:grid;gap:.4em}
.prose ol{list-style:decimal;padding-left:1.3em;margin-top:.8em;display:grid;gap:.4em}
.prose strong{font-weight:600;color:var(--ink-900)}
.section--ink .prose strong{color:var(--paper)}
.mono-note{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.12em;
  line-height:1.8;
  color:var(--slate);
}
.section-head{display:grid;gap:10px;margin-bottom:clamp(20px,3vw,32px)}
.section-head__title{
  font-family:var(--font-display);
  font-size:clamp(24px,3.4vw,40px);
  font-weight:700;
  line-height:1.25;
  letter-spacing:-.01em;
}
.section-head__text{max-width:62ch;font-size:16px;line-height:1.85;color:var(--slate)}

/* ===== 08 按钮 ===== */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:.55rem;
  padding:.82rem 1.45rem;
  border-radius:var(--radius-pill);
  border:1px solid transparent;
  background:transparent;
  font-family:var(--font-body);
  font-size:15px;
  font-weight:600;
  line-height:1.2;
  letter-spacing:.01em;
  text-align:center;
  text-decoration:none;
  cursor:pointer;
  transition:background-color var(--dur) var(--ease),color var(--dur) var(--ease),border-color var(--dur) var(--ease),transform var(--dur) var(--ease),box-shadow var(--dur) var(--ease);
}
.btn:focus-visible{outline:2px solid var(--coral);outline-offset:2px}
.btn:hover{transform:translateY(-2px)}
.btn--primary{background:var(--coral);color:var(--ink-950);border-color:var(--coral)}
.btn--primary:hover{background:#ff7157;box-shadow:0 14px 28px -18px var(--coral)}
.btn--ghost{background:transparent;color:var(--paper);border-color:rgba(185,130,69,.55)}
.btn--ghost:hover{background:rgba(185,130,69,.2);border-color:var(--copper);color:var(--paper)}
.btn--outline{background:transparent;color:var(--ink-text);border-color:rgba(19,35,47,.24)}
.btn--outline:hover{background:rgba(27,64,88,.07);border-color:var(--ink-700)}
.btn--sm{padding:.55rem 1.05rem;font-size:13px}

/* ===== 09 标签 ===== */
.tag{
  display:inline-flex;
  align-items:center;
  gap:.45rem;
  padding:.42rem .9rem;
  border-radius:var(--radius-pill);
  border:var(--hair);
  background:rgba(201,216,226,.3);
  color:var(--ink-700);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.06em;
  line-height:1.4;
  text-decoration:none;
  cursor:pointer;
  transition:background-color var(--dur) var(--ease),color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.tag:hover{background:var(--copper-light);border-color:rgba(185,130,69,.6);color:var(--ink-900)}
.tag:focus-visible{outline:2px solid var(--coral);outline-offset:2px}
.tag--active,
.tag[aria-pressed="true"]{background:var(--coral);border-color:var(--coral);color:var(--ink-950);font-weight:500}
.tag__count{font-size:11px;opacity:.72;letter-spacing:.04em}
.section--ink .tag{background:rgba(201,216,226,.1);border-color:rgba(201,216,226,.2);color:var(--mist-200)}
.section--ink .tag:hover{background:rgba(233,201,161,.95);color:var(--ink-900)}
.section--ink .tag--active,
.section--ink .tag[aria-pressed="true"]{background:var(--coral);border-color:var(--coral);color:var(--ink-950)}

/* ===== 10 卡片 ===== */
.card{
  position:relative;
  display:grid;
  gap:10px;
  align-content:start;
  padding:clamp(18px,2.4vw,26px);
  border-radius:var(--radius-lg);
  border:var(--hair);
  background:var(--paper);
  box-shadow:var(--shadow-soft);
  transition:transform var(--dur) var(--ease),border-color var(--dur) var(--ease),box-shadow var(--dur) var(--ease);
}
.card:hover{
  transform:translateY(-2px);
  border-color:rgba(185,130,69,.45);
  box-shadow:0 16px 34px -24px rgba(7,21,33,.7);
}
.card__title{
  font-family:var(--font-display);
  font-size:clamp(18px,2vw,22px);
  font-weight:700;
  line-height:1.4;
  letter-spacing:.01em;
  color:var(--ink-900);
}
.card__text{font-size:15px;line-height:1.8;color:var(--slate)}
.section--ink .card{background:var(--ink-950);border-color:rgba(201,216,226,.16);box-shadow:none}
.section--ink .card:hover{border-color:rgba(185,130,69,.55)}
.section--ink .card__title{color:var(--paper)}

/* ===== 11 面包屑 ===== */
.breadcrumb{margin-bottom:clamp(18px,2.6vw,28px)}
.breadcrumb__list{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:.5rem;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.14em;
  color:var(--slate);
}
.breadcrumb__list li{display:inline-flex;align-items:center;gap:.5rem}
.breadcrumb__list li+li::before{content:"/";color:var(--copper);opacity:.75}
.breadcrumb__link{
  color:var(--copper);
  border-bottom:1px solid transparent;
  transition:border-color var(--dur) var(--ease),color var(--dur) var(--ease);
}
.breadcrumb__link:hover{color:var(--ink-900);border-bottom-color:currentColor}
.breadcrumb__current{color:var(--slate)}

/* ===== 12 图片容器基础规则 ===== */
.media{
  position:relative;
  isolation:isolate;
  overflow:hidden;
  display:block;
  width:100%;
  aspect-ratio:16/10;
  border-radius:var(--radius-lg);
  background:linear-gradient(145deg,var(--ink-900),var(--ink-700) 65%,#254c62);
}
.media__img{width:100%;height:100%;object-fit:cover;display:block}
.media::after{
  content:"";
  position:absolute;
  inset:0;
  z-index:1;
  pointer-events:none;
  background:linear-gradient(202deg,rgba(7,21,33,0) 42%,rgba(7,21,33,.58));
}
.media--wide{aspect-ratio:21/9}
.media--square{aspect-ratio:1/1}
.media--portrait{aspect-ratio:3/4}
.media__caption{
  position:absolute;
  left:16px;
  right:16px;
  bottom:14px;
  z-index:2;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.12em;
  line-height:1.6;
  color:var(--copper-light);
}
@media (min-width:768px){
  .media{border-radius:var(--radius-xl)}
  .media__caption{left:22px;right:22px;bottom:20px;font-size:12px}
}

/* ===== 13 平板与桌面：框架式侧栏导航 ===== */
@media (min-width:640px){
  .site-nav__list{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-cols{grid-template-columns:repeat(3,minmax(0,1fr))}
  .footer-guide__inner{grid-template-columns:minmax(0,1fr) auto;row-gap:14px}
  .footer-guide__head{grid-column:1/-1}
  .footer-guide__text{grid-column:1/2}
  .footer-guide__link{grid-column:2/3;justify-self:end}
}
@media (min-width:900px){
  .footer-body{grid-template-columns:minmax(0,1fr) minmax(0,1.55fr) minmax(0,1fr);align-items:start}
  .footer-guide__inner{grid-template-columns:minmax(0,1.05fr) minmax(0,1.4fr) auto;align-items:center}
  .footer-guide__head{grid-column:auto}
  .footer-guide__text{grid-column:auto}
  .footer-guide__link{grid-column:auto}
}
@media (min-width:1024px){
  body{padding-left:var(--rail-w)}
  #main-content{scroll-margin-top:24px}
  .site-header{
    position:fixed;
    inset:0 auto 0 0;
    width:var(--rail-w);
    border-bottom:0;
    border-right:1px solid rgba(185,130,69,.3);
    overflow-y:auto;
    overflow-x:hidden;
    background:linear-gradient(180deg,var(--ink-950) 0%,#081827 62%,var(--ink-900) 100%);
  }
  .site-header__inner{
    flex-direction:column;
    flex-wrap:nowrap;
    align-items:stretch;
    justify-content:flex-start;
    gap:0;
    min-height:100%;
    padding:26px 20px 24px;
  }
  .brand{padding-bottom:20px;border-bottom:var(--hair-soft)}
  .nav-toggle{display:none}
  .site-nav{
    order:0;
    flex:1 1 auto;
    max-height:none;
    width:auto;
    padding:20px 0 0;
    overflow:visible;
    opacity:1;
    visibility:visible;
    transition:none;
  }
  .site-nav__list{grid-template-columns:1fr;gap:2px;padding-top:12px}
  .site-nav__link{padding:9px 12px;font-size:15px}
  .rail-guide{margin-top:20px}
  .rail-foot{margin-top:auto;padding-top:22px}
  .scroll-progress{left:var(--rail-w)}
}

/* ===== 14 减少动态效果 ===== */
@media (prefers-reduced-motion: reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  .btn:hover,
  .card:hover{transform:none}
  .scroll-progress__bar{transition:none}
  .site-nav,
  .site-header[data-open] .site-nav{transition:none}
}