:root{
  --ink-900:#0F1B3D;
  --indigo-800:#16264F;
  --indigo-600:#22376B;
  --mist:#E9EDF5;
  --jade:#17A88B;
  --jade-deep:#0E7C67;
  --gold:#E4B34A;
  --gold-soft:#F4DFAE;
  --ink:#16233A;
  --muted:#5B6B85;
  --paper:#F7F9FC;
  --alert:#C8553D;
  --font-sans:"HarmonyOS Sans SC","Source Han Sans SC","PingFang SC",system-ui,-apple-system,"Microsoft YaHei",sans-serif;
  --font-mono:"JetBrains Mono","SFMono-Regular",ui-monospace,Menlo,Consolas,monospace;
  --gutter:6vw;
  --maxw:1440px;
  --cut-sm:polygon(7px 0,100% 0,100% calc(100% - 7px),calc(100% - 7px) 100%,0 100%,0 7px);
  --cut-md:polygon(12px 0,100% 0,100% calc(100% - 12px),calc(100% - 12px) 100%,0 100%,0 12px);
  --cut-lg:polygon(22px 0,100% 0,100% calc(100% - 22px),calc(100% - 22px) 100%,0 100%,0 22px);
  --ease:cubic-bezier(.22,.61,.36,1);
}

*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;
  font-family:var(--font-sans);
  font-size:17px;
  line-height:1.85;
  letter-spacing:.01em;
  color:var(--ink);
  background-color:var(--mist);
  background-image:repeating-linear-gradient(135deg,rgba(15,27,61,.022) 0 1px,transparent 1px 14px);
  -webkit-font-smoothing:antialiased;
}
h1,h2,h3,h4{margin:0 0 .6em;font-weight:800;line-height:1.18;letter-spacing:-.02em}
h1{font-size:clamp(2rem,4.4vw,3.4rem)}
h2{font-size:clamp(1.5rem,2.6vw,2.2rem)}
h3{font-size:clamp(1.15rem,1.8vw,1.5rem)}
p{margin:0 0 1em}
ul,ol{margin:0 0 1em;padding-left:1.2em}
img,svg{max-width:100%;display:block}
a{color:var(--jade-deep);text-decoration:none}
a:hover{color:var(--ink-900)}
button{font:inherit;color:inherit}
[hidden]{display:none !important}
:focus-visible{outline:2px solid var(--jade);outline-offset:3px}

.wrap{width:100%;max-width:var(--maxw);margin:0 auto;padding-left:var(--gutter);padding-right:var(--gutter)}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}
.mono{font-family:var(--font-mono);letter-spacing:.04em}

/* ---------- skip link ---------- */
.skip-link{
  position:absolute;left:14px;top:-72px;z-index:140;
  padding:10px 18px;background:var(--jade);color:#04140F;
  font-weight:700;font-size:14px;letter-spacing:.04em;clip-path:var(--cut-sm);
  transition:top .18s var(--ease);
}
.skip-link:focus{top:14px;color:#04140F}

/* ---------- header ---------- */
.site-header{
  position:sticky;top:0;z-index:80;
  background:var(--ink-900);
  color:var(--paper);
  border-bottom:1px solid var(--indigo-600);
}
.header-inner{max-width:1560px}
.header-top{
  display:flex;align-items:center;gap:24px;
  padding:16px 0;max-height:140px;overflow:hidden;
  border-bottom:1px solid rgba(34,55,107,.9);
  transition:max-height .26s var(--ease),opacity .22s var(--ease),padding .26s var(--ease),border-color .22s var(--ease);
}
.site-header[data-scrolled="true"] .header-top{max-height:0;opacity:0;padding-top:0;padding-bottom:0;border-color:transparent}
.brand{display:flex;align-items:center;gap:13px;color:inherit;text-decoration:none}
.brand-mark{
  position:relative;flex:0 0 auto;width:38px;height:38px;
  background:linear-gradient(140deg,var(--jade) 0%,var(--jade-deep) 68%,var(--indigo-600) 100%);
  clip-path:polygon(0 0,100% 0,100% 62%,62% 100%,0 100%);
}
.brand-mark::after{content:"";position:absolute;left:9px;top:16px;width:20px;height:2px;background:rgba(247,249,252,.85);transform:rotate(-34deg)}
.brand-copy{display:flex;flex-direction:column;line-height:1.32}
.brand-name{font-size:19px;font-weight:800;letter-spacing:-.01em;color:var(--paper)}
.brand-sub{font-family:var(--font-mono);font-size:11.5px;letter-spacing:.06em;color:rgba(233,237,245,.6)}
.brand-line{margin:0;font-size:14px;color:rgba(233,237,245,.72);padding-left:24px;border-left:1px solid var(--indigo-600)}
.header-meta{margin-left:auto;display:flex;align-items:center;gap:12px;flex-wrap:wrap}
.status-tag{
  display:inline-flex;align-items:center;gap:8px;
  font-family:var(--font-mono);font-size:11.5px;letter-spacing:.05em;
  color:rgba(233,237,245,.78);border:1px solid var(--indigo-600);
  padding:5px 10px;background:rgba(22,38,79,.6);
}
.status-dot{width:7px;height:7px;background:var(--jade);border-radius:50%;flex:0 0 auto}

.header-bar{position:relative;display:flex;align-items:center;gap:18px;padding:11px 0}
.nav{display:flex;align-items:center;gap:22px;flex:1 1 auto;min-width:0}
.nav-list{display:flex;align-items:center;gap:6px;list-style:none;margin:0;padding:0}
.nav-list-brand .nav-link{font-size:13.5px;color:rgba(233,237,245,.66);font-weight:600}
.nav-seam{width:1px;height:20px;background:var(--indigo-600);flex:0 0 auto}
.nav-link{
  position:relative;display:inline-block;padding:9px 13px;
  color:rgba(247,249,252,.86);font-size:15px;font-weight:600;letter-spacing:.02em;
  clip-path:var(--cut-sm);
  transition:background-color .18s var(--ease),color .18s var(--ease);
}
.nav-link::after{
  content:"";position:absolute;left:0;bottom:0;height:2px;width:100%;
  background:var(--jade);transform:scaleX(0);transform-origin:left;
  transition:transform .18s var(--ease);
}
.nav-link:hover{background:var(--indigo-600);color:#fff}
.nav-link:hover::after{transform:scaleX(1)}
.nav-link[aria-current="page"]{background:var(--indigo-600);color:#fff}
.nav-link[aria-current="page"]::after{transform:scaleX(1)}

.header-tools{display:flex;align-items:center;gap:10px;margin-left:auto;flex:0 0 auto}

.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:11px 20px;font-size:15px;font-weight:700;letter-spacing:.03em;
  border:1px solid transparent;background:transparent;color:inherit;cursor:pointer;
  clip-path:var(--cut-sm);
  transition:transform .18s var(--ease),background-color .18s var(--ease),border-color .18s var(--ease),color .18s var(--ease),box-shadow .18s var(--ease);
}
.btn-sm{padding:8px 14px;font-size:13px}
.btn-jade{background:var(--jade);color:#04140F}
.btn-jade:hover{background:var(--jade-deep);color:#F2FFFB;transform:translateY(-2px)}
.btn-line{border-color:var(--indigo-600);color:var(--paper)}
.btn-line:hover{border-color:var(--jade);color:#fff;background:rgba(23,168,139,.14)}
.btn-ghost{border-color:rgba(233,237,245,.3);color:var(--paper)}
.btn-ghost:hover{border-color:var(--gold);color:var(--gold-soft)}
.btn-gold{background:var(--gold);color:#221806}
.btn-gold:hover{background:var(--gold-soft);transform:translateY(-2px)}

.nav-toggle{
  display:none;align-items:center;gap:10px;order:3;
  padding:9px 14px;background:var(--indigo-800);border:1px solid var(--indigo-600);
  color:var(--paper);font-size:12.5px;font-weight:700;letter-spacing:.08em;
  cursor:pointer;clip-path:var(--cut-sm);
}
.nav-toggle-box{display:grid;gap:4px;width:18px}
.nav-toggle-bar{display:block;height:2px;background:var(--jade);transition:transform .18s var(--ease),opacity .18s var(--ease)}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1){transform:translateY(6px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2){opacity:0}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3){transform:translateY(-6px) rotate(-45deg)}

/* ---------- search ---------- */
.search{position:relative;flex:0 1 296px;min-width:0}
.search-field{
  display:flex;align-items:center;gap:9px;
  padding:4px 6px 4px 12px;background:var(--indigo-800);
  border:1px solid var(--indigo-600);clip-path:var(--cut-sm);
  transition:border-color .18s var(--ease),background-color .18s var(--ease);
}
.search[data-active="true"] .search-field,
.search-field:focus-within{border-color:var(--jade);background:#0D1C3C}
.search-icon{position:relative;flex:0 0 auto;width:12px;height:12px;border:1.5px solid var(--jade);border-radius:50%}
.search-icon::after{content:"";position:absolute;right:-5px;bottom:-4px;width:7px;height:1.5px;background:var(--jade);transform:rotate(45deg)}
.search-input{
  flex:1 1 auto;min-width:0;border:0;background:transparent;outline:none;
  color:var(--paper);font-family:var(--font-sans);font-size:14px;line-height:1.6;padding:8px 0;
}
.search-input::placeholder{color:rgba(233,237,245,.5)}
.search-key{
  flex:0 0 auto;font-family:var(--font-mono);font-size:10.5px;letter-spacing:.08em;
  color:var(--jade);border:1px solid rgba(23,168,139,.45);padding:3px 7px;
}
.search-panel{
  position:absolute;top:calc(100% + 10px);right:0;width:min(360px,86vw);
  padding:16px;background:var(--indigo-800);border:1px solid var(--indigo-600);
  clip-path:var(--cut-md);box-shadow:0 24px 48px rgba(5,10,24,.5);z-index:95;
}
.search-panel-title{margin:0 0 10px;font-family:var(--font-mono);font-size:10.5px;letter-spacing:.2em;color:var(--jade)}
.search-chips{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:14px}
.chip{
  font-family:var(--font-mono);font-size:12px;letter-spacing:.03em;
  padding:5px 10px;background:transparent;border:1px solid var(--indigo-600);
  color:rgba(233,237,245,.8);cursor:pointer;clip-path:var(--cut-sm);
  transition:background-color .18s var(--ease),border-color .18s var(--ease),color .18s var(--ease);
}
.chip:hover{border-color:var(--jade);color:#fff}
.chip[aria-pressed="true"]{background:rgba(23,168,139,.2);border-color:var(--jade);color:#EAFFF9}
.search-results{list-style:none;margin:0;padding:0;display:grid;gap:4px}
.search-result-link{
  display:flex;align-items:baseline;justify-content:space-between;gap:12px;
  padding:9px 10px;color:var(--paper);border-left:2px solid transparent;
  transition:background-color .18s var(--ease),border-color .18s var(--ease);
}
.search-result-link:hover{background:var(--indigo-600);border-left-color:var(--jade);color:#fff}
.search-result-name{font-size:14px;font-weight:600}
.search-result-meta{font-family:var(--font-mono);font-size:10.5px;letter-spacing:.04em;color:rgba(233,237,245,.55)}
.search-empty{margin:8px 0 0;font-size:12.5px;color:var(--gold-soft)}

/* ---------- footer ---------- */
.site-footer{position:relative;background:var(--ink-900);color:var(--paper);overflow:hidden}
.site-footer::before{
  content:"";position:absolute;inset:0;pointer-events:none;
  background-image:repeating-linear-gradient(135deg,rgba(233,237,245,.028) 0 1px,transparent 1px 16px);
}
.footer-lead{position:relative;background:var(--indigo-800);border-bottom:1px solid var(--indigo-600)}
.lead-out{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(4,minmax(0,1fr))}
.lead-cell{min-width:0}
.lead-item{
  display:flex;flex-direction:column;gap:6px;height:100%;
  padding:26px 22px;color:var(--paper);border-right:1px solid var(--indigo-600);
  transition:background-color .18s var(--ease),transform .18s var(--ease);
}
.lead-item:hover{background:var(--indigo-600);color:#fff;transform:translateY(-4px)}
.lead-index{font-family:var(--font-mono);font-size:12px;letter-spacing:.1em;color:var(--jade)}
.lead-label{font-size:17px;font-weight:800;letter-spacing:-.01em}
.lead-note{font-size:12.5px;line-height:1.65;color:rgba(233,237,245,.62)}
.footer-main{position:relative;display:grid;grid-template-columns:1.05fr 1.6fr;gap:48px;padding-top:54px;padding-bottom:40px}
.footer-brand{display:flex;flex-direction:column;gap:14px}
.brand--footer .brand-name{font-size:18px}
.footer-desc{margin:0;font-size:14px;line-height:1.8;color:rgba(233,237,245,.68);max-width:36ch}
.footer-status{
  display:inline-flex;align-items:center;gap:8px;margin:0;
  font-family:var(--font-mono);font-size:11.5px;letter-spacing:.05em;
  color:var(--gold-soft);border:1px solid rgba(228,179,74,.4);padding:5px 11px;align-self:flex-start;
}
.footer-cols{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:32px}
.footer-col-title{margin:0 0 14px;font-family:var(--font-mono);font-size:11.5px;font-weight:500;letter-spacing:.18em;color:var(--jade)}
.footer-links{list-style:none;margin:0;padding:0;display:grid;gap:10px}
.footer-links a{font-size:14.5px;color:rgba(233,237,245,.78);border-bottom:1px solid transparent;transition:color .18s var(--ease),border-color .18s var(--ease)}
.footer-links a:hover{color:#fff;border-bottom-color:var(--jade)}
.footer-contact{list-style:none;margin:0;padding:0;display:grid;gap:13px}
.footer-contact-key{display:block;font-family:var(--font-mono);font-size:10.5px;letter-spacing:.14em;color:rgba(233,237,245,.5);margin-bottom:3px}
.footer-contact-value{display:block;font-size:14px;line-height:1.7;color:rgba(233,237,245,.82)}
.footer-contact-value.mono{color:var(--gold-soft)}
.footer-base{
  position:relative;display:flex;flex-wrap:wrap;gap:10px 28px;align-items:baseline;justify-content:space-between;
  padding-top:20px;padding-bottom:32px;border-top:1px solid var(--indigo-600);
  font-size:12.5px;line-height:1.7;color:rgba(233,237,245,.56);
}
.footer-legal,.footer-note,.footer-year{margin:0}
.footer-note{flex:1 1 420px;max-width:70ch}
.footer-year{font-family:var(--font-mono);letter-spacing:.04em;color:rgba(233,237,245,.68)}

/* ---------- typography helpers ---------- */
.display-1{font-size:clamp(3rem,7vw,6rem);line-height:1.04;letter-spacing:-.03em;font-weight:800}
.lede{font-size:clamp(1rem,1.35vw,1.15rem);line-height:1.8;color:var(--muted);max-width:62ch}
.eyebrow{display:inline-flex;align-items:center;gap:9px;font-family:var(--font-mono);font-size:11.5px;letter-spacing:.18em;color:var(--jade-deep)}
.eyebrow::before{content:"";width:22px;height:2px;background:var(--jade)}
.section-dark .lede,.section-deep .lede{color:rgba(233,237,245,.72)}
.section-dark .eyebrow,.section-deep .eyebrow{color:var(--jade)}

/* ---------- section shells ---------- */
.section{padding:64px 0;position:relative}
.section-dark{background:var(--ink-900);color:var(--paper)}
.section-deep{background:var(--indigo-800);color:var(--paper)}
.section-light{background:var(--paper);color:var(--ink)}
.section-mist{background:var(--mist);color:var(--ink)}
.section-head{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,34ch);gap:20px 32px;align-items:end;margin-bottom:34px}
.section-title{margin:0;font-size:clamp(1.6rem,2.8vw,2.4rem)}
.section-lead{margin:0;font-size:14.5px;line-height:1.8;color:var(--muted)}
.section-dark .section-lead,.section-deep .section-lead{color:rgba(233,237,245,.68)}

/* ---------- chapter band ---------- */
.chapter-band{
  display:grid;grid-template-columns:auto minmax(0,1fr) auto;gap:16px 28px;align-items:baseline;
  padding:22px 26px;background:var(--indigo-800);color:var(--paper);
  clip-path:var(--cut-md);margin-bottom:30px;
}
.chapter-band--deep{background:var(--ink-900)}
.chapter-band--mid{background:var(--indigo-600)}
.chapter-band--light{background:var(--paper);color:var(--ink);box-shadow:inset 0 0 0 1px rgba(34,55,107,.16)}
.chapter-no{font-family:var(--font-mono);font-weight:500;font-size:clamp(2.5rem,5vw,4.5rem);line-height:1;letter-spacing:.02em;color:rgba(23,168,139,.46)}
.chapter-title{margin:0;font-size:clamp(1.3rem,2.2vw,1.9rem)}
.chapter-desc{margin:0;font-size:13.5px;line-height:1.7;color:rgba(233,237,245,.68);max-width:38ch}
.chapter-band--light .chapter-desc{color:var(--muted)}

/* ---------- panels, cards, grids ---------- */
.panel{
  background:var(--indigo-800);color:var(--paper);padding:26px;
  clip-path:var(--cut-md);border:1px solid var(--indigo-600);
}
.panel .lede{color:rgba(233,237,245,.72)}
.grid{display:grid;gap:22px}
.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;display:block;padding:24px 24px 24px 30px;
  background:var(--paper);color:var(--ink);text-decoration:none;
  border:1px solid rgba(34,55,107,.16);clip-path:var(--cut-md);
  transition:transform .18s var(--ease),box-shadow .18s var(--ease),border-color .18s var(--ease);
}
.card::before{
  content:"";position:absolute;left:0;top:0;bottom:0;width:4px;background:var(--jade);
  transform:scaleY(0);transform-origin:top;transition:transform .18s var(--ease);
}
.card:hover,.card:focus-visible{transform:translateY(-4px);box-shadow:0 16px 34px rgba(15,27,61,.18);border-color:rgba(23,168,139,.5);color:var(--ink)}
.card:hover::before,.card:focus-visible::before{transform:scaleY(1)}
.card-title{display:block;margin:0 0 8px;font-size:18px;font-weight:800;letter-spacing:-.01em}
.card-text{margin:0;font-size:14.5px;line-height:1.8;color:var(--muted)}
.card-meta{
  display:inline-block;margin-top:14px;font-family:var(--font-mono);
  font-size:11px;letter-spacing:.08em;color:var(--jade-deep);
}

/* ---------- index grid ---------- */
.index-grid{list-style:none;margin:0;padding:0;display:grid}
.index-item{
  display:grid;grid-template-columns:64px minmax(0,1fr);gap:8px 20px;align-items:baseline;
  padding:16px 8px;color:var(--ink);border-top:1px solid rgba(34,55,107,.16);
  background-image:repeating-linear-gradient(135deg,rgba(23,168,139,.07) 0 1px,transparent 1px 11px);
  transition:background-color .18s var(--ease),color .18s var(--ease);
}
.index-item:last-child{border-bottom:1px solid rgba(34,55,107,.16)}
.index-item:hover{background-color:rgba(23,168,139,.08);color:var(--ink-900)}
.index-no{font-family:var(--font-mono);font-size:13px;letter-spacing:.06em;color:var(--jade-deep)}

/* ---------- motion trail ---------- */
.motion-trail{position:relative;height:88px;max-width:var(--maxw);margin:0 auto;padding-left:var(--gutter);padding-right:var(--gutter)}
.motion-trail::before{
  content:"";position:absolute;left:var(--gutter);right:var(--gutter);top:50%;height:2px;
  background:linear-gradient(90deg,rgba(23,168,139,0),var(--jade) 16%,var(--jade) 84%,rgba(23,168,139,0));
  transform-origin:left;animation:trail-draw .7s var(--ease) both;
}
.trail-node{
  position:absolute;left:var(--x,50%);top:50%;width:11px;height:11px;margin-top:-5.5px;
  transform:translateX(-50%);background:var(--paper);border:2px solid var(--jade);
  transition:background-color .24s var(--ease),box-shadow .24s var(--ease);
}
.trail-node.is-visible{background:var(--jade);box-shadow:0 0 0 5px rgba(23,168,139,.16)}
@keyframes trail-draw{from{transform:scaleX(0)}to{transform:scaleX(1)}}

/* ---------- media ---------- */
.media-frame{
  position:relative;display:block;overflow:hidden;aspect-ratio:16/9;
  background:linear-gradient(160deg,var(--indigo-800),var(--ink-900));
  clip-path:var(--cut-md);
}
.media-frame--wide{aspect-ratio:21/9}
.media-frame--tall{aspect-ratio:4/5}
.media-frame img{width:100%;height:100%;object-fit:cover;display:block}
.media-fallback{
  display:flex;align-items:flex-end;width:100%;height:100%;padding:18px;
  font-family:var(--font-mono);font-size:11.5px;letter-spacing:.1em;color:rgba(233,237,245,.5);
  background-image:repeating-linear-gradient(135deg,rgba(23,168,139,.12) 0 1px,transparent 1px 14px);
}
.media-caption{display:block;margin-top:10px;font-size:12.5px;line-height:1.7;color:var(--muted)}

/* ---------- tags ---------- */
.tag{
  display:inline-flex;align-items:center;gap:6px;padding:4px 10px;
  font-family:var(--font-mono);font-size:11.5px;letter-spacing:.04em;
  border:1px solid transparent;
}
.tag-jade{background:rgba(23,168,139,.12);border-color:rgba(23,168,139,.36);color:var(--jade-deep)}
.tag-gold{background:var(--gold-soft);border-color:rgba(228,179,74,.5);color:#6A4C05}
.tag-alert{background:rgba(200,85,61,.1);border-color:rgba(200,85,61,.4);color:var(--alert)}
.tag-ink{background:var(--indigo-800);border-color:var(--indigo-600);color:var(--paper)}

/* ---------- prose, breadcrumb, chapter rail ---------- */
.prose{max-width:72ch}
.prose p,.prose li{font-size:16.5px;line-height:1.85}
.prose h2{margin-top:1.6em}
.prose h3{margin-top:1.3em}
.breadcrumb{
  display:flex;flex-wrap:wrap;align-items:center;gap:8px;
  margin:0 0 18px;font-family:var(--font-mono);font-size:12px;letter-spacing:.04em;color:var(--muted);
}
.breadcrumb a{color:var(--jade-deep)}
.breadcrumb-sep{color:rgba(91,107,133,.55)}
.chapter-rail{display:grid;gap:2px;align-content:start}
.chapter-rail-link{
  display:block;padding:9px 12px;font-size:13.5px;color:var(--muted);
  border-left:2px solid rgba(34,55,107,.24);transition:color .18s var(--ease),border-color .18s var(--ease),background-color .18s var(--ease);
}
.chapter-rail-link:hover{color:var(--ink-900);background:rgba(23,168,139,.08)}
.chapter-rail-link[aria-current="true"]{color:var(--jade-deep);border-left-color:var(--jade);background:rgba(23,168,139,.1)}

/* ---------- reveal ---------- */
.has-js [data-reveal]{opacity:0;transform:translateY(14px);transition:opacity .32s var(--ease),transform .32s var(--ease)}
.has-js [data-reveal].is-visible{opacity:1;transform:none}

/* ---------- responsive ---------- */
@media (max-width:1100px){
  .grid-4,.grid-3{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-main{grid-template-columns:1fr;gap:38px}
}
@media (max-width:960px){
  .wrap{max-width:none}
  .header-bar{flex-wrap:nowrap;gap:10px}
  .nav-toggle{display:inline-flex}
  .header-tools{order:2;margin-left:auto}
  .nav{
    position:absolute;left:0;right:0;top:calc(100% + 10px);
    display:none;flex-direction:column;align-items:stretch;gap:6px;
    padding:14px;background:var(--indigo-800);border:1px solid var(--indigo-600);
    clip-path:var(--cut-md);box-shadow:0 24px 48px rgba(5,10,24,.5);z-index:90;
  }
  .nav[data-open="true"]{display:flex}
  .nav-list{flex-direction:column;align-items:stretch;gap:2px;width:100%}
  .nav-list-brand .nav-link{font-size:14px;color:rgba(233,237,245,.72)}
  .nav-seam{display:none}
  .nav-link{display:block;padding:12px 14px;font-size:16px;background:rgba(15,27,61,.42)}
  .search{flex:0 1 240px}
}
@media (max-width:900px){
  :root{--gutter:5vw}
}
@media (max-width:760px){
  .search{display:none}
  .brand-line{display:none}
  .header-top{flex-wrap:wrap;gap:14px}
  .header-meta{margin-left:0}
  .chapter-band{grid-template-columns:auto minmax(0,1fr);padding:18px}
  .chapter-desc{grid-column:1 / -1}
  .section{padding:48px 0}
  .section-head{grid-template-columns:minmax(0,1fr);align-items:start}
  .index-item{grid-template-columns:48px minmax(0,1fr)}
}
@media (max-width:1024px){
  .lead-out{grid-template-columns:repeat(2,minmax(0,1fr))}
  .lead-cell:nth-child(2n) .lead-item{border-right:0}
  .lead-cell:nth-child(-n+2) .lead-item{border-bottom:1px solid var(--indigo-600)}
}
@media (max-width:680px){
  .grid-2,.grid-3,.grid-4{grid-template-columns:minmax(0,1fr)}
  .footer-cols{grid-template-columns:minmax(0,1fr);gap:26px}
  .lead-out{grid-template-columns:minmax(0,1fr)}
  .lead-item{border-right:0;border-bottom:1px solid var(--indigo-600)}
  .lead-cell:nth-child(-n+2) .lead-item{border-bottom:1px solid var(--indigo-600)}
  .footer-base{flex-direction:column;align-items:flex-start}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  .has-js [data-reveal]{opacity:1;transform:none}
  .card:hover,.card:focus-visible,.btn:hover,.lead-item:hover{transform:none}
  .motion-trail::before{animation:none;transform:scaleX(1)}
}