:root{
  --bg:#faf9f7;
  --paper:#ffffff;
  --ink:#1d1d26;
  --mute:#5d5f70;
  --line:#e3e2ea;
  --accent:#4f46e5;
  --accent-soft:#eceafd;
  --code-bg:#f2f1f8;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{
  margin:0;background:var(--bg);color:var(--ink);
  font-family:system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  font-size:17px;line-height:1.65;overflow-x:hidden;
}
a{color:var(--accent);text-underline-offset:3px}
a:hover{color:#3730a3}
.page{max-width:860px;margin:0 auto;padding:0 20px}
.masthead{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:12px;padding:28px 0 12px}
.brand{font-size:1.45rem;font-weight:800;letter-spacing:-.02em;color:var(--ink);text-decoration:none}
.brand b{color:var(--accent)}
.menu{display:flex;flex-wrap:wrap;gap:6px 22px}
.menu a{color:var(--mute);text-decoration:none;font-size:.95rem;padding:4px 0;border-bottom:2px solid transparent}
.menu a:hover,.menu a.here{color:var(--ink);border-bottom-color:var(--accent)}
.intro{padding:56px 0 36px;max-width:680px}
.intro h1{font-size:clamp(2rem,6vw,3.1rem);line-height:1.12;letter-spacing:-.03em;margin:0 0 20px}
.intro p{font-size:1.15rem;color:var(--mute);margin:0}
.plain{padding:40px 0 10px}
.plain h1{font-size:clamp(1.8rem,5vw,2.5rem);letter-spacing:-.025em;line-height:1.15;margin:0 0 12px}
.lede{color:var(--mute);font-size:1.1rem;margin:0 0 20px}
h2{font-size:1.5rem;letter-spacing:-.02em;margin:56px 0 16px;line-height:1.25}
h3{font-size:1.12rem;margin:30px 0 6px}
p{margin:0 0 16px}
.figure{margin:20px 0 8px}
.figure svg{display:block;width:100%;height:auto}
.caption{color:var(--mute);font-size:.9rem;margin-top:10px}
.steps{display:flex;flex-wrap:wrap;gap:20px;margin:0;padding:0;list-style:none}
.step{flex:1 1 210px;background:var(--paper);border:1px solid var(--line);border-radius:16px;padding:20px}
.step svg{display:block;width:100%;max-width:200px;height:auto;margin:0 auto 12px}
.step h3{margin:0 0 4px}
.step p{margin:0;color:var(--mute);font-size:.97rem}
.feats{list-style:none;margin:0;padding:0;display:flex;flex-wrap:wrap;gap:0 40px}
.feats li{flex:1 1 300px;padding:14px 0 14px 28px;border-bottom:1px solid var(--line);position:relative}
.feats li::before{content:"";position:absolute;left:4px;top:23px;width:10px;height:10px;border-radius:50%;background:var(--accent)}
.feats strong{display:block}
.feats span{color:var(--mute);font-size:.96rem}
.codebox{background:var(--code-bg);border:1px solid var(--line);border-radius:10px;padding:14px 16px;margin:0 0 18px;overflow-x:auto;max-width:100%}
.codebox code,.codebox pre{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:.88rem;line-height:1.55;white-space:pre;margin:0}
code{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:.9em;background:var(--code-bg);padding:1px 5px;border-radius:4px}
.codebox code{background:none;padding:0}
.spec{overflow-x:auto;max-width:100%;margin:0 0 20px}
.spec table{border-collapse:collapse;width:100%;min-width:560px;font-size:.93rem;background:var(--paper)}
.spec th,.spec td{border:1px solid var(--line);padding:9px 12px;text-align:left;vertical-align:top}
.spec th{background:var(--accent-soft)}
.aside{border-left:4px solid var(--accent);background:var(--accent-soft);padding:12px 16px;border-radius:0 10px 10px 0;margin:0 0 18px}
.aside p{margin:0}
.qa{border-bottom:1px solid var(--line);padding:6px 0 12px}
.qa h3{margin-top:20px}
.qa p{margin:0 0 8px}
.rel{border-left:3px solid var(--line);padding:2px 0 2px 18px;margin:0 0 30px}
.rel h2{margin:0 0 2px;font-size:1.25rem}
.rel time{color:var(--mute);font-size:.9rem}
.rel ul{margin:10px 0 0;padding-left:20px}
.rel li{margin-bottom:4px}
.foot{margin-top:72px;padding:26px 0 40px;border-top:1px solid var(--line);color:var(--mute);font-size:.9rem;display:flex;flex-wrap:wrap;justify-content:space-between;gap:10px}
.foot a{color:var(--mute)}
@media (max-width:520px){
  body{font-size:16px}
  .intro{padding-top:32px}
}
/* svg mockups */
svg text{font-family:system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif}
svg .mono{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace}