/* ===== reset ===== */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body,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{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
img,svg{display:block;max-width:100%}
table{border-collapse:collapse}

/* ===== tokens ===== */
:root{
  --abyss:#060B18;
  --plateau:#0E1730;
  --indigo:#1A2750;
  --orange:#F4571C;
  --orange-lit:#FF8A3D;
  --glacier:#38CFE0;
  --butter:#F3C46A;
  --star:#E9EEF8;
  --mist:#93A2C2;
  --verify:#45DDB0;
  --body-ink:#CBD5EA;
  --line:rgba(147,162,194,.18);
  --line-strong:rgba(147,162,194,.34);
  --frame-grad:linear-gradient(160deg,#0E1730 0%,#123E5C 55%,#0B2840 100%);
  --shell:1240px;
  --gutter:clamp(16px,4vw,40px);
  --cut:22px;
  --slant:8deg;
  --ease:cubic-bezier(.22,.61,.36,1);
  --font-display:"Noto Sans SC","Source Han Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","PingFang SC",system-ui,-apple-system,"Helvetica Neue",sans-serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --font-serif:"Noto Serif SC","Source Han Serif SC",Georgia,"Songti SC",serif;
  --header-h:78px;
  --pill:999px;
  --panel-r:20px;
}

/* ===== base ===== */
body{
  min-height:100vh;
  background-color:var(--abyss);
  color:var(--star);
  font-family:var(--font-body);
  font-size:17px;
  line-height:1.8;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
body::before{
  content:"";position:fixed;inset:0;z-index:-1;pointer-events:none;
  background:
    radial-gradient(900px 520px at 84% -10%,rgba(56,207,224,.16),transparent 70%),
    radial-gradient(720px 480px at 6% 12%,rgba(244,87,28,.13),transparent 72%),
    radial-gradient(1100px 720px at 50% 118%,rgba(26,39,80,.6),transparent 68%);
}
h1,h2,h3,h4{font-family:var(--font-display);font-weight:900;letter-spacing:.09em;line-height:1.28}
:focus-visible{outline:2px solid var(--orange);outline-offset:3px;border-radius:8px}
::selection{background:rgba(244,87,28,.38);color:#fff}

.skip-link{
  position:fixed;top:10px;left:10px;z-index:200;
  transform:translateY(-190%);
  padding:10px 20px;border-radius:var(--pill);
  background:linear-gradient(135deg,var(--orange-lit),var(--orange));
  color:#12060a;font-weight:700;letter-spacing:.08em;font-size:14px;
  transition:transform .3s var(--ease);
}
.skip-link:focus{transform:translateY(0);color:#12060a}

/* ===== header ===== */
.site-header{
  position:fixed;top:0;left:0;right:0;z-index:60;
  padding:12px var(--gutter);
  transition:padding .35s var(--ease);
}
.scroll-progress{
  position:absolute;top:0;left:0;right:0;height:3px;
  background:rgba(147,162,194,.14);
}
.scroll-progress > i{
  display:block;height:100%;width:0;
  background:linear-gradient(90deg,var(--glacier),var(--orange-lit),var(--orange));
}
.header-rail{
  max-width:var(--shell);margin:0 auto;
  display:flex;align-items:center;justify-content:space-between;gap:14px;
}
.brand-capsule{
  display:inline-flex;align-items:center;gap:12px;flex:none;
  padding:8px 20px 8px 14px;border-radius:var(--pill);
  background:rgba(14,23,48,.74);
  border:1px solid var(--line);
  -webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);
  box-shadow:0 14px 32px rgba(3,6,16,.55);
  transition:border-color .3s var(--ease),padding .35s var(--ease),background-color .3s var(--ease);
}
.brand-capsule:hover{border-color:rgba(244,87,28,.55);background:rgba(20,31,62,.85)}
.brand-mark{display:flex;align-items:flex-end;gap:3px;width:26px;height:26px;flex:none}
.brand-mark i{
  display:block;width:5px;border-radius:2px;transform-origin:bottom center;
  animation:flagSway 5s var(--ease) infinite;
}
.brand-mark i:nth-child(1){height:58%;background:var(--orange)}
.brand-mark i:nth-child(2){height:100%;background:var(--glacier);animation-delay:.6s}
.brand-mark i:nth-child(3){height:72%;background:var(--butter);animation-delay:1.1s}
@keyframes flagSway{
  0%,100%{transform:scaleY(1) skewX(0deg)}
  50%{transform:scaleY(.86) skewX(-5deg)}
}
.brand-text{display:block;min-width:0}
.brand-name{
  display:block;font-family:var(--font-display);font-weight:900;
  font-size:16px;letter-spacing:.15em;line-height:1.25;color:var(--star);
}
.brand-tagline{
  display:block;font-family:var(--font-mono);font-size:10px;letter-spacing:.14em;
  color:var(--mist);line-height:1.6;max-height:20px;overflow:hidden;
  transition:max-height .35s var(--ease),opacity .3s var(--ease);
}
.site-header[data-condensed]{padding-top:8px;padding-bottom:8px}
.site-header[data-condensed] .brand-capsule{padding:6px 16px 6px 12px;background:rgba(9,15,33,.86)}
.site-header[data-condensed] .brand-tagline{max-height:0;opacity:0}

.site-nav{
  display:flex;align-items:center;gap:8px;padding:6px;
  border-radius:var(--pill);
  background:rgba(10,17,36,.72);
  border:1px solid var(--line);
  -webkit-backdrop-filter:blur(16px);backdrop-filter:blur(16px);
  box-shadow:0 16px 36px rgba(3,6,16,.58);
}
.nav-list{display:flex;align-items:center;gap:2px}
.nav-link{
  display:inline-flex;align-items:center;gap:6px;
  padding:9px 15px;border-radius:var(--pill);
  font-size:14px;letter-spacing:.08em;color:var(--mist);white-space:nowrap;
  transition:color .25s var(--ease),background-color .25s var(--ease);
}
.nav-link:hover{color:var(--star);background:rgba(56,207,224,.13)}
.nav-link[aria-current="page"]{
  color:#12060a;font-weight:700;
  background:linear-gradient(135deg,var(--orange-lit),var(--orange));
  box-shadow:0 8px 20px rgba(244,87,28,.34);
}
.nav-link[aria-current="page"]::before{
  content:"";width:6px;height:6px;border-radius:50%;background:#12060a;flex:none;
}
.nav-actions{
  display:flex;align-items:center;gap:8px;
  margin-left:6px;padding-left:10px;border-left:1px solid var(--line);
}

.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:10px 18px;border-radius:var(--pill);
  font-family:var(--font-display);font-weight:700;font-size:14px;letter-spacing:.08em;
  border:1px solid transparent;cursor:pointer;white-space:nowrap;
  transition:transform .25s var(--ease),box-shadow .25s var(--ease),background-color .25s var(--ease),border-color .25s var(--ease),color .25s var(--ease);
}
.btn:hover{transform:translateY(-2px)}
.btn:active{transform:translateY(0)}
.btn-primary{
  background:linear-gradient(135deg,var(--orange-lit),var(--orange));
  color:#12060a;box-shadow:0 10px 24px rgba(244,87,28,.3);
}
.btn-primary:hover{box-shadow:0 14px 30px rgba(244,87,28,.44)}
.btn-ghost{
  border-color:var(--line-strong);color:var(--star);background:rgba(14,23,48,.55);
}
.btn-ghost:hover{border-color:var(--glacier);color:var(--glacier);background:rgba(56,207,224,.1)}

.nav-toggle{
  display:none;align-items:center;gap:10px;
  padding:10px 16px;border-radius:var(--pill);
  background:rgba(14,23,48,.8);border:1px solid var(--line);
  -webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);
  color:var(--star);transition:border-color .3s var(--ease),background-color .3s var(--ease);
}
.nav-toggle-label{font-size:13px;letter-spacing:.1em;color:var(--mist)}
.nav-toggle-bars{display:inline-flex;flex-direction:column;gap:5px;width:20px;flex:none}
.nav-toggle-bars i{
  display:block;height:2px;width:100%;background:var(--orange);border-radius:2px;
  transform-origin:center;transition:transform .3s var(--ease);
}
.nav-toggle[aria-expanded="true"]{border-color:rgba(244,87,28,.6);background:rgba(26,39,80,.9)}
.nav-toggle[aria-expanded="true"] .nav-toggle-label{color:var(--star)}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:first-child{transform:translateY(3.5px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:last-child{transform:translateY(-3.5px) rotate(-45deg)}

/* ===== main shell ===== */
#main-content{display:block;scroll-margin-top:calc(var(--header-h) + 16px);padding-top:calc(var(--header-h) + clamp(10px,2vw,22px))}
.main-offset{padding-top:calc(var(--header-h) + clamp(10px,2vw,22px))}
.main-flush{padding-top:0}

.wrap{width:100%;max-width:var(--shell);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-block:clamp(40px,6vw,78px);position:relative}
.section-head{
  display:flex;flex-wrap:wrap;align-items:flex-end;justify-content:space-between;gap:14px;
  margin-bottom:clamp(20px,3vw,36px);
}
.eyebrow{
  display:inline-flex;align-items:center;gap:9px;
  font-family:var(--font-mono);font-size:11.5px;letter-spacing:.28em;text-transform:uppercase;
  color:var(--glacier);
}
.eyebrow::before{content:"";width:24px;height:2px;background:linear-gradient(90deg,var(--glacier),var(--orange))}

.chapter{display:flex;gap:16px;align-items:flex-start}
.chapter-num{
  font-family:var(--font-mono);font-weight:700;
  font-size:clamp(30px,5vw,58px);line-height:1;letter-spacing:.02em;
  color:transparent;-webkit-text-stroke:1.4px rgba(244,87,28,.78);
}
.chapter-title{
  font-family:var(--font-display);font-weight:900;
  font-size:clamp(22px,3vw,30px);letter-spacing:.1em;line-height:1.26;color:var(--star);
}
.chapter-sub{font-family:var(--font-serif);font-size:13px;letter-spacing:.2em;color:var(--mist)}
.lead{font-size:clamp(16px,1.6vw,18px);color:var(--body-ink);max-width:62ch}

.prose{max-width:70ch;color:var(--body-ink)}
.prose p{margin-bottom:1.1em}
.prose h2{font-size:24px;margin:1.7em 0 .6em;color:var(--star)}
.prose h3{font-size:19px;margin:1.5em 0 .5em;color:var(--star)}
.prose ul{margin:0 0 1.1em}
.prose li{position:relative;padding-left:20px;margin-bottom:.55em;color:var(--mist)}
.prose li::before{content:"";position:absolute;left:0;top:.75em;width:9px;height:2px;background:var(--orange)}
.prose a{color:var(--orange-lit);border-bottom:1px solid rgba(255,138,61,.45)}
.prose a:hover{color:var(--glacier);border-bottom-color:rgba(56,207,224,.6)}

/* ===== panels & labels ===== */
.panel{
  position:relative;
  background:linear-gradient(165deg,rgba(26,39,80,.55),rgba(14,23,48,.88));
  border:1px solid var(--line);
  border-radius:var(--panel-r);
  padding:clamp(20px,3vw,32px);
}
.panel-notch{
  border-radius:0;
  -webkit-clip-path:polygon(var(--cut) 0,100% 0,100% calc(100% - var(--cut)),calc(100% - var(--cut)) 100%,0 100%,0 var(--cut));
  clip-path:polygon(var(--cut) 0,100% 0,100% calc(100% - var(--cut)),calc(100% - var(--cut)) 100%,0 100%,0 var(--cut));
}
.panel-notch::before{
  content:"";position:absolute;left:0;top:var(--cut);width:2px;height:clamp(32px,10%,64px);
  background:linear-gradient(180deg,var(--orange),transparent);
}

.tag{
  display:inline-flex;align-items:center;gap:6px;
  padding:4px 11px;border-radius:var(--pill);
  font-family:var(--font-mono);font-size:11.5px;letter-spacing:.08em;
  border:1px solid var(--line-strong);color:var(--mist);white-space:nowrap;
}
.tag-orange{border-color:rgba(244,87,28,.48);color:var(--orange-lit);background:rgba(244,87,28,.1)}
.tag-cyan{border-color:rgba(56,207,224,.42);color:var(--glacier);background:rgba(56,207,224,.1)}
.tag-verify{border-color:rgba(69,221,176,.42);color:var(--verify);background:rgba(69,221,176,.1)}
.tag-butter{border-color:rgba(243,196,106,.42);color:var(--butter);background:rgba(243,196,106,.1)}

.metric{display:flex;flex-direction:column;gap:6px}
.metric-value{
  font-family:var(--font-mono);font-weight:700;
  font-size:clamp(42px,7.4vw,90px);line-height:.95;letter-spacing:-.02em;color:var(--star);
}
.metric-value .unit{font-size:.32em;letter-spacing:.12em;color:var(--orange);margin-left:.24em}
.metric-label{font-family:var(--font-mono);font-size:12.5px;letter-spacing:.16em;color:var(--mist)}

.divider-slash{
  height:1px;margin-block:clamp(28px,5vw,58px);position:relative;
  background:linear-gradient(90deg,transparent,var(--line-strong),transparent);
}
.divider-slash::after{
  content:"";position:absolute;left:50%;top:-3px;width:36px;height:7px;
  transform:translateX(-50%) skewX(calc(var(--slant) * -1));
  background:linear-gradient(90deg,var(--orange),var(--glacier));
}

/* ===== grid ===== */
.grid{display:grid;gap:clamp(16px,2.4vw,26px)}
.grid-2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid-3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid-split{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1.7fr);gap:clamp(20px,4vw,58px);align-items:start}

/* ===== breadcrumb ===== */
.breadcrumb{padding-block:14px}
.crumb-list{display:flex;flex-wrap:wrap;align-items:center;gap:8px;font-family:var(--font-mono);font-size:12px;color:var(--mist)}
.crumb-list li{display:inline-flex;align-items:center;gap:8px}
.crumb-list li + li::before{content:"/";color:rgba(147,162,194,.5)}
.crumb-list a:hover{color:var(--glacier)}
.crumb-list [aria-current="page"]{color:var(--butter)}

/* ===== figure / image containers ===== */
.figure-frame{
  position:relative;margin:0;overflow:hidden;
  border:1px solid var(--line);border-radius:var(--panel-r);
  background:linear-gradient(160deg,#0E1730,#0B2840);
}
.figure-frame::after{
  content:"";position:absolute;inset:10px;pointer-events:none;
  border:1px solid rgba(147,162,194,.14);border-radius:12px;
}
.figure-media{
  position:relative;display:block;width:100%;aspect-ratio:16/9;
  background:
    radial-gradient(120% 120% at 22% 0%,rgba(56,207,224,.18),transparent 62%),
    linear-gradient(160deg,#0E1730,#08101F);
}
.figure-media img{width:100%;height:100%;object-fit:cover}
.figure-media.is-portrait{aspect-ratio:3/4}
.figure-media.is-square{aspect-ratio:1/1}
.figure-media.is-wide{aspect-ratio:21/9}
.figure-caption{
  display:flex;flex-wrap:wrap;align-items:center;gap:10px;
  padding:12px 16px;border-top:1px dashed var(--line-strong);
  font-family:var(--font-mono);font-size:12px;color:var(--mist);
}
.figure-caption .tag{padding:2px 9px;font-size:10.5px}

/* ===== table ===== */
.table-scroll{
  overflow-x:auto;border:1px solid var(--line);border-radius:var(--panel-r);
  background:rgba(14,23,48,.62);
}
.table-scroll table{width:100%;min-width:560px;font-size:14px}
.table-scroll th,.table-scroll td{padding:12px 16px;text-align:left;border-bottom:1px solid var(--line)}
.table-scroll th{
  font-family:var(--font-display);font-weight:700;font-size:12.5px;letter-spacing:.12em;
  color:var(--mist);background:rgba(26,39,80,.55);
}
.table-scroll td{color:var(--body-ink)}
.table-scroll td.num{font-family:var(--font-mono);color:var(--orange-lit)}
.table-scroll tbody tr:last-child td{border-bottom:0}

/* ===== reveal ===== */
.has-js [data-reveal]{
  opacity:0;transform:translateY(20px);
  transition:opacity .42s var(--ease),transform .42s var(--ease);
  transition-delay:var(--reveal-delay,0ms);
}
.has-js [data-reveal].is-visible{opacity:1;transform:none}

/* ===== footer ===== */
.site-footer{
  position:relative;overflow:hidden;
  margin-top:clamp(64px,10vw,124px);
  padding:clamp(48px,7vw,86px) 0 30px;
  background:linear-gradient(180deg,rgba(14,23,48,0) 0%,rgba(14,23,48,.86) 26%,#08101F 100%);
  border-top:1px solid var(--line);
}
.site-footer::before{
  content:"";position:absolute;top:0;left:0;right:0;height:2px;
  background:linear-gradient(90deg,transparent,var(--glacier),var(--orange),transparent);
  opacity:.75;
}
.footer-slash{
  position:absolute;top:-70px;right:-90px;width:300px;height:300px;pointer-events:none;
  border-radius:40px;transform:rotate(var(--slant));
  background:linear-gradient(150deg,rgba(56,207,224,.14),rgba(244,87,28,.07));
}
.footer-rail{position:relative;max-width:var(--shell);margin:0 auto;padding-inline:var(--gutter)}
.footer-brand{
  display:flex;flex-wrap:wrap;align-items:baseline;gap:8px 20px;
  padding-bottom:22px;border-bottom:1px solid var(--line);
}
.footer-brand-name{
  font-family:var(--font-display);font-weight:900;
  font-size:clamp(20px,3vw,26px);letter-spacing:.16em;color:var(--star);
}
.footer-tagline{font-family:var(--font-mono);font-size:12px;letter-spacing:.16em;color:var(--glacier)}
.footer-grid{
  display:grid;grid-template-columns:repeat(4,minmax(0,1fr));
  gap:clamp(22px,3vw,42px);padding:32px 0;
}
.footer-col{min-width:0}
.footer-col-title{
  position:relative;font-family:var(--font-serif);font-weight:400;
  font-size:14px;letter-spacing:.24em;color:var(--star);
  padding-bottom:10px;margin-bottom:13px;border-bottom:1px dashed var(--line-strong);
}
.footer-col-title::after{
  content:"";position:absolute;left:0;bottom:-1px;width:28px;height:2px;background:var(--orange);
}
.footer-links{display:flex;flex-direction:column;gap:9px}
.footer-links a{
  font-size:14px;color:var(--mist);letter-spacing:.04em;
  transition:color .25s var(--ease),padding-left .25s var(--ease);
}
.footer-links a:hover{color:var(--orange-lit);padding-left:6px}
.footer-contact{display:flex;flex-direction:column;gap:8px}
.footer-contact-line{
  font-family:var(--font-mono);font-size:12.5px;letter-spacing:.02em;
  color:var(--star);word-break:break-all;
}
.footer-address{font-size:13px;line-height:1.75;color:var(--mist)}
.footer-note{font-size:12px;line-height:1.7;color:var(--mist);opacity:.86}
.footer-meta{
  display:flex;flex-wrap:wrap;align-items:center;gap:10px 18px;
  padding-top:20px;border-top:1px solid var(--line);
  font-size:12px;color:var(--mist);
}
.footer-icp{
  font-family:var(--font-mono);letter-spacing:.06em;color:var(--butter);
  padding:3px 11px;border:1px solid rgba(243,196,106,.32);border-radius:var(--pill);
}
.footer-copyright{letter-spacing:.06em}

/* ===== to-top ===== */
.to-top{
  position:fixed;right:clamp(14px,3vw,30px);bottom:clamp(18px,4vw,34px);z-index:55;
  width:48px;height:48px;display:inline-flex;align-items:center;justify-content:center;
  font-family:var(--font-mono);font-size:16px;
  background:rgba(14,23,48,.88);border:1px solid var(--line-strong);color:var(--star);
  -webkit-clip-path:polygon(11px 0,100% 0,100% calc(100% - 11px),calc(100% - 11px) 100%,0 100%,0 11px);
  clip-path:polygon(11px 0,100% 0,100% calc(100% - 11px),calc(100% - 11px) 100%,0 100%,0 11px);
  opacity:0;visibility:hidden;transform:translateY(10px);
  transition:opacity .3s var(--ease),transform .3s var(--ease),visibility .3s var(--ease),border-color .3s var(--ease),color .3s var(--ease);
}
.to-top[data-visible]{opacity:1;visibility:visible;transform:none}
.to-top:hover{border-color:var(--orange);color:var(--orange-lit)}

/* ===== responsive ===== */
@media (max-width:1080px){
  .nav-toggle{display:inline-flex}
  .site-nav{
    position:fixed;top:calc(var(--header-h) + 4px);left:var(--gutter);right:var(--gutter);
    flex-direction:column;align-items:stretch;gap:10px;padding:14px;
    border-radius:26px;
    background:linear-gradient(160deg,rgba(14,23,48,.98),rgba(9,18,36,.98));
    max-height:calc(100vh - var(--header-h) - 34px);overflow-y:auto;
    opacity:0;visibility:hidden;transform:translateY(-12px) scale(.98);
    transition:opacity .3s var(--ease),transform .3s var(--ease),visibility .3s var(--ease);
  }
  .site-nav[data-open]{opacity:1;visibility:visible;transform:none}
  .nav-list{flex-direction:column;align-items:stretch;width:100%;gap:2px}
  .nav-link{
    width:100%;justify-content:flex-start;padding:13px 16px;border-radius:14px;
    font-size:16px;letter-spacing:.06em;
  }
  .nav-actions{
    flex-direction:column;align-items:stretch;
    margin-left:0;padding-left:0;padding-top:12px;
    border-left:0;border-top:1px solid var(--line);
  }
  .nav-actions .btn{width:100%}
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:900px){
  .grid-2,.grid-3,.grid-split{grid-template-columns:1fr}
}
@media (max-width:640px){
  :root{--cut:16px}
  .brand-tagline{display:none}
  .nav-toggle-label{display:none}
  .footer-grid{grid-template-columns:1fr;gap:26px}
  .footer-brand{gap:6px 14px}
  .footer-slash{width:200px;height:200px;top:-50px;right:-70px}
  .figure-caption{font-size:11px}
}
@media (max-width:380px){
  .brand-capsule{padding:6px 12px 6px 10px}
  .brand-name{font-size:14px;letter-spacing:.1em}
}

/* ===== motion preference ===== */
@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 !important;transform:none !important}
  .btn:hover{transform:none}
}