:root{
  --bg:#F3F5F7;
  --surface:#FFFFFF;
  --ink:#0B1B33;
  --muted:#5E6A79;
  --line:#CCD3DC;
  --blue:#A97924;
  --blue-soft:#E0BC72;
  --navy:#071426;
  --maxw:1280px;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  background:var(--bg);color:var(--ink);
  font-family:'Archivo',sans-serif;
  font-size:16px;line-height:1.65;
  -webkit-font-smoothing:antialiased;
}
.mono{font-family:'JetBrains Mono',monospace}
a{color:inherit;text-decoration:none}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 44px}
:focus-visible{outline:2px solid var(--blue);outline-offset:4px}

/* header */
header{position:fixed;top:0;left:0;right:0;z-index:100;background:rgba(243,245,247,.94);backdrop-filter:blur(14px);border-bottom:1px solid var(--line)}
.nav{display:flex;align-items:center;justify-content:space-between;height:76px}
.logo{display:flex;align-items:center}
.logo img{height:22px;width:auto;display:block}
.nav-links{display:flex;gap:34px;font-size:13px;font-weight:600;letter-spacing:.02em;align-items:center}
.nav-links a{position:relative;transition:color .25s}
.nav-links a::after{content:"";position:absolute;left:0;bottom:-4px;width:0;height:2px;background:var(--blue);transition:width .3s cubic-bezier(.16,1,.3,1)}
.nav-links a:hover{color:var(--blue)}
.nav-links a:hover::after{width:100%}

/* page head */
.page-head{padding:170px 0 60px;border-bottom:1px solid var(--line);background:linear-gradient(90deg,rgba(255,255,255,.6),transparent 70%)}
.sec-index{font-family:'JetBrains Mono',monospace;font-size:12px;font-weight:500;color:var(--blue);letter-spacing:.08em;text-transform:uppercase;display:flex;align-items:center;gap:12px}
.sec-index::before{content:"";width:32px;height:1px;background:var(--blue)}
.page-head h1{font-size:clamp(36px,5vw,64px);font-weight:600;letter-spacing:-0.035em;line-height:1.02;margin-top:26px;max-width:820px}
.page-meta{margin-top:26px;font-family:'JetBrains Mono',monospace;font-size:12px;text-transform:uppercase;letter-spacing:.08em;color:var(--muted)}

/* content */
.content{padding-top:70px;padding-bottom:110px;display:grid;grid-template-columns:260px minmax(0,760px);gap:64px}
.toc{position:sticky;top:110px;align-self:start;font-size:13.5px}
.toc b{display:block;font-family:'JetBrains Mono',monospace;font-size:11px;text-transform:uppercase;letter-spacing:.1em;color:var(--muted);margin-bottom:14px;font-weight:500}
.toc a{display:block;padding:6px 0;color:var(--muted);border-left:2px solid var(--line);padding-left:14px;transition:color .2s,border-color .2s}
.toc a:hover{color:var(--ink);border-color:var(--blue)}

.prose>p{color:#3F4C5D;margin-bottom:18px;max-width:70ch}
.prose .lead{font-size:18px;color:var(--ink)}
.prose h2{font-size:clamp(22px,2.4vw,30px);font-weight:600;letter-spacing:-0.02em;margin:56px 0 18px;scroll-margin-top:110px;display:flex;align-items:baseline;gap:14px}
.prose h2 .n{font-family:'JetBrains Mono',monospace;font-size:13px;color:var(--blue);font-weight:500;flex:none}
.prose h3{font-size:17px;font-weight:600;margin:30px 0 10px}
.prose ul{margin:0 0 18px 0;padding-left:0;list-style:none;max-width:70ch}
.prose ul li{position:relative;padding-left:22px;margin-bottom:8px;color:#3F4C5D}
.prose ul li::before{content:"—";position:absolute;left:0;color:var(--blue)}
.prose a{color:var(--ink);text-decoration:underline;text-underline-offset:3px;text-decoration-color:var(--blue);transition:color .2s}
.prose a:hover{color:var(--blue)}

/* definition card */
.def-card{background:var(--surface);border:1px solid var(--line);border-top:3px solid var(--ink);border-radius:3px;padding:8px 26px;margin:22px 0 30px;max-width:640px;box-shadow:0 12px 34px rgba(11,27,51,.05)}
.def-row{display:grid;grid-template-columns:190px 1fr;gap:18px;padding:15px 0;border-bottom:1px solid var(--line);font-size:14.5px}
.def-row:last-child{border-bottom:none}
.def-row dt{font-family:'JetBrains Mono',monospace;font-size:11px;text-transform:uppercase;letter-spacing:.08em;color:var(--muted);padding-top:2px}
.def-row dd{color:var(--ink)}

/* footer */
footer{background:var(--navy);color:#8491A2;font-size:13px;margin-top:40px}
.foot-bottom{display:flex;justify-content:space-between;flex-wrap:wrap;gap:14px;padding:26px 0;font-family:'JetBrains Mono',monospace;font-size:11px;text-transform:uppercase;letter-spacing:.06em}
.foot-links{display:flex;gap:24px}
.foot-links a:hover{color:var(--bg)}

@media(max-width:900px){
  .wrap{padding:0 24px}
  .nav-links{display:none}
  .content{grid-template-columns:1fr;gap:40px;padding-top:50px;padding-bottom:80px}
  .toc{position:static}
  .page-head{padding:140px 0 50px}
  .def-row{grid-template-columns:1fr;gap:4px}
}

/* Quiet glass corporate system */
:root{
  --bg:#F5F7FC;
  --surface:rgba(255,255,255,.60);
  --ink:#10172A;
  --muted:#667086;
  --line:rgba(77,96,148,.16);
  --blue:#2400FF;
  --blue-soft:#6868FF;
  --navy:#111A73;
}
body{
  background:
    radial-gradient(circle at 82% 8%,rgba(36,0,255,.10),transparent 30%),
    radial-gradient(circle at 8% 44%,rgba(126,184,255,.12),transparent 28%),
    linear-gradient(180deg,#F7F9FD,#F2F6FB 65%,#F8FAFD);
  background-attachment:fixed;
}
header{padding:16px 0;background:transparent;border:0;backdrop-filter:none}
.nav{height:68px;padding:0 24px;border:1px solid rgba(255,255,255,.84);border-radius:22px;background:rgba(255,255,255,.55);box-shadow:0 12px 42px rgba(55,75,128,.09),inset 0 1px 0 #fff;-webkit-backdrop-filter:blur(20px) saturate(145%);backdrop-filter:blur(20px) saturate(145%)}
.nav-links{font-size:13px;font-weight:500}
.page-head{padding:180px 0 76px;border:0;background:transparent}
.page-head .wrap{padding-top:36px;padding-bottom:36px;border:1px solid rgba(255,255,255,.86);border-radius:28px;background:rgba(255,255,255,.46);box-shadow:0 24px 80px rgba(53,75,130,.09),inset 0 1px 0 #fff;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px)}
.sec-index{font-size:10px;letter-spacing:.13em;color:var(--blue)}
.page-head h1{font-weight:500;letter-spacing:-.045em}
.content{grid-template-columns:240px minmax(0,780px);gap:70px}
.toc{padding:22px;border:1px solid rgba(255,255,255,.86);border-radius:20px;background:rgba(255,255,255,.40);box-shadow:0 18px 54px rgba(53,75,130,.07),inset 0 1px 0 #fff;-webkit-backdrop-filter:blur(18px);backdrop-filter:blur(18px)}
.toc a{border-left:1px solid var(--line)}
.prose h2{font-weight:500;letter-spacing:-.03em}
.def-card{border:1px solid rgba(255,255,255,.88);border-top:1px solid rgba(255,255,255,.88);border-radius:22px;background:rgba(255,255,255,.52);box-shadow:0 20px 64px rgba(53,75,130,.09),inset 0 1px 0 #fff;-webkit-backdrop-filter:blur(18px);backdrop-filter:blur(18px)}
footer{background:transparent;color:var(--muted)}
.foot-bottom{border-top:1px solid var(--line)}
.foot-links a:hover{color:var(--blue)}

@media(max-width:900px){
  header{padding:10px 0}
  .nav{height:58px;padding:0 16px;border-radius:18px}
  .page-head{padding:126px 0 42px}
  .page-head .wrap{margin:0 12px;padding:28px 24px;border-radius:24px}
  .content{grid-template-columns:1fr;gap:32px}
  .toc{padding:20px;border-radius:18px}
}