/* Sealed First — site styles. Layout: narrow editorial column, one hero with the sealed-envelope mechanism shown as a live card. */
:root{
  --bg:#F2F4F7; --surface:#FFFFFF; --sunk:#E8ECF2; --ink:#161D2B; --muted:#586274; --line:#D6DCE5;
  --accent:#2E49C9; --accent-ink:#FFFFFF; --accent-soft:#E4E9FB;
  --good:#1D7448; --warn:#9A5B00; --rt:#7A3E9E;
  --hatch:rgba(46,73,201,.10);
  --f-display:"Spectral",Georgia,"Times New Roman",serif;
  --f-body:"Public Sans",system-ui,-apple-system,"Segoe UI",sans-serif;
  --f-mono:"JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,monospace;
  color-scheme:light;
}
@media (prefers-color-scheme: dark){:root:not([data-theme="light"]){
  --bg:#0F131A; --surface:#161C26; --sunk:#1D2430; --ink:#E5E9F1; --muted:#9AA4B5; --line:#2A3342;
  --accent:#8FA2FF; --accent-ink:#0F131A; --accent-soft:#232D4D;
  --good:#5BC28D; --warn:#E2A54D; --rt:#C9A0E8; --hatch:rgba(143,162,255,.12); color-scheme:dark}}
:root[data-theme="dark"]{
  --bg:#0F131A; --surface:#161C26; --sunk:#1D2430; --ink:#E5E9F1; --muted:#9AA4B5; --line:#2A3342;
  --accent:#8FA2FF; --accent-ink:#0F131A; --accent-soft:#232D4D;
  --good:#5BC28D; --warn:#E2A54D; --rt:#C9A0E8; --hatch:rgba(143,162,255,.12); color-scheme:dark}

*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--f-body);font-size:16px;line-height:1.6;padding-inline:20px}
a{color:var(--accent);text-underline-offset:3px}
a:focus-visible,button:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:4px}
h1,h2,h3{font-family:var(--f-display);text-wrap:balance;margin:0;line-height:1.12;letter-spacing:-.01em}
h1{font-size:clamp(2.3rem,6vw,3.6rem);font-weight:700}
h2{font-size:clamp(1.6rem,3.6vw,2.1rem);font-weight:600}
h3{font-size:1.15rem;font-weight:600}
p{margin:0}
.wrap{max-width:1040px;margin:0 auto}
.narrow{max-width:66ch}
.label{font-size:.74rem;text-transform:uppercase;letter-spacing:.09em;font-weight:600;color:var(--muted)}
.muted{color:var(--muted)}
.mono{font-family:var(--f-mono);font-size:.85em}

/* nav */
.nav{display:flex;align-items:center;justify-content:space-between;gap:16px;padding-block:20px;flex-wrap:wrap}
.brand{display:flex;align-items:center;gap:10px;font-family:var(--f-display);font-weight:700;font-size:1.2rem;color:var(--ink);text-decoration:none}
.brand svg{width:26px;height:26px}
.nav nav{display:flex;gap:18px;flex-wrap:wrap;font-size:.95rem}
.nav nav a{color:var(--ink);text-decoration:none;font-weight:500}
.nav nav a:hover{color:var(--accent)}

/* buttons */
.btn{display:inline-flex;align-items:center;gap:8px;font:inherit;font-weight:600;font-size:1rem;padding:12px 18px;border-radius:9px;border:1px solid var(--line);background:var(--surface);color:var(--ink);text-decoration:none;cursor:pointer}
.btn:hover{border-color:var(--accent)}
.btn.primary{background:var(--accent);color:var(--accent-ink);border-color:var(--accent)}
.row{display:flex;gap:10px;flex-wrap:wrap;align-items:center}

/* sections */
section{padding-block:56px;border-top:1px solid var(--line)}
section.first{border-top:0;padding-block:28px 64px}
.stack{display:flex;flex-direction:column;gap:16px}
.grid2{display:grid;grid-template-columns:minmax(0,1.05fr) minmax(0,1fr);gap:48px;align-items:center}
.grid3{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}
.lede{font-size:1.15rem;color:var(--muted);max-width:56ch}

/* hero card: the mechanism */
.mech{background:var(--surface);border:1px solid var(--line);border-radius:14px;padding:20px;display:flex;flex-direction:column;gap:12px;box-shadow:0 18px 40px -28px rgba(22,29,43,.35)}
.mech .q{font-family:var(--f-display);font-size:1.15rem;font-weight:600;line-height:1.3}
.sealed{border:1.5px dashed var(--accent);border-radius:9px;padding:12px 14px;background:repeating-linear-gradient(135deg,var(--hatch) 0 6px,transparent 6px 12px);display:flex;justify-content:space-between;align-items:center;gap:10px;flex-wrap:wrap}
.sealed strong{font-size:.95rem}
.pair{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.side{border:1px solid var(--line);border-radius:9px;padding:12px;background:var(--bg);display:flex;flex-direction:column;gap:4px;min-width:0;font-size:.92rem}
.side.ai{border-color:var(--accent)}
.chips{display:flex;gap:6px;flex-wrap:wrap}
.chip{font-size:.75rem;font-weight:600;padding:3px 10px;border-radius:999px;background:var(--sunk);color:var(--muted)}
.chip.on{background:var(--accent);color:var(--accent-ink)}
.ok{font-size:.8rem;color:var(--good)}
.mech-step{display:flex;gap:10px;align-items:baseline}
.mech-step .n{font-family:var(--f-mono);font-size:.75rem;color:var(--muted);min-width:1.4em}

/* steps */
ol.steps{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:16px;counter-reset:s}
ol.steps li{counter-increment:s;display:flex;flex-direction:column;gap:8px;padding-top:14px;border-top:2px solid var(--accent)}
ol.steps li::before{content:"0" counter(s);font-family:var(--f-mono);font-size:.8rem;color:var(--accent);font-weight:500}
ol.steps p{color:var(--muted);font-size:.95rem}

/* cards */
.card{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:20px;display:flex;flex-direction:column;gap:12px;min-width:0}
.card p{color:var(--muted);font-size:.95rem}
.card .foot{margin-top:auto;display:flex;flex-direction:column;gap:10px}
pre.cmd{margin:0;background:var(--sunk);border-radius:8px;padding:10px 12px;font-family:var(--f-mono);font-size:.78rem;white-space:pre-wrap;overflow-wrap:anywhere;color:var(--ink)}

/* score */
.weights{display:flex;flex-direction:column;gap:12px}
.w{display:grid;grid-template-columns:minmax(0,1fr) 3rem;gap:4px 12px;align-items:center}
.w .v{text-align:right;font-variant-numeric:tabular-nums;font-weight:600}
.bar{grid-column:1/-1;height:7px;border-radius:4px;background:var(--sunk);overflow:hidden}
.bar i{display:block;height:100%;background:var(--accent);border-radius:4px}
.w small{grid-column:1/-1;color:var(--muted);font-size:.85rem}

/* quote */
.pull{font-family:var(--f-display);font-size:clamp(1.4rem,3vw,1.9rem);line-height:1.3;font-weight:500;max-width:30ch;text-wrap:balance}

/* lists */
ul.clean{margin:0;padding-left:1.2em;display:flex;flex-direction:column;gap:8px}
.statuses{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:10px}
.status{border:1px solid var(--line);border-left:5px solid var(--muted);border-radius:9px;padding:12px 14px;background:var(--surface);display:flex;flex-direction:column;gap:4px}
.status b{font-family:var(--f-display);font-size:1.05rem}
.status span{color:var(--muted);font-size:.88rem}
.status.good{border-left-color:var(--good)} .status.warn{border-left-color:var(--warn)} .status.bad{border-left-color:#AE2F29}

/* footer */
footer{border-top:1px solid var(--line);padding-block:28px 40px;display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap;color:var(--muted);font-size:.9rem}
footer a{color:var(--muted)}

@media (max-width:860px){
  .grid2{grid-template-columns:1fr;gap:32px}
  .grid3{grid-template-columns:1fr}
  ol.steps{grid-template-columns:1fr 1fr}
}
@media (max-width:520px){
  body{padding-inline:16px}
  ol.steps{grid-template-columns:1fr}
  .pair{grid-template-columns:1fr}
  section{padding-block:44px}
}
@media (prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important}}