:root{
  --bg:#0e1013;--bg2:#161a20;--card:#1b2028;--line:#2a313c;
  --text:#e8ecf2;--muted:#9aa5b5;--accent:#ff8a1f;--accent2:#ffb15c;--ok:#3ecf8e;
  --r:14px;--w:1080px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--text);font:17px/1.65 system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif;-webkit-font-smoothing:antialiased}
a{color:var(--accent2);text-decoration:none}
a:hover{text-decoration:underline}
img,svg{max-width:100%}
.wrap{max-width:var(--w);margin:0 auto;padding:0 16px}
header.site{position:sticky;top:0;z-index:10;background:rgba(14,16,19,.92);backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}
header.site .wrap{display:flex;align-items:center;justify-content:space-between;gap:16px;height:60px}
.logo{font-weight:800;font-size:19px;color:var(--text);letter-spacing:.3px}
.logo b{color:var(--accent)}
nav.main{display:flex;gap:4px;flex-wrap:wrap}
nav.main a{color:var(--muted);padding:6px 10px;border-radius:8px;font-size:15px}
nav.main a:hover,nav.main a.on{color:var(--text);background:var(--card);text-decoration:none}
.hero{padding:64px 0 40px;background:radial-gradient(900px 300px at 20% -10%,rgba(255,138,31,.18),transparent),var(--bg)}
.hero h1{font-size:clamp(30px,5vw,48px);line-height:1.15;margin:0 0 16px;max-width:760px}
.hero p{color:var(--muted);max-width:640px;font-size:19px;margin:0 0 24px}
.btn{display:inline-block;background:var(--accent);color:#1a0f00;font-weight:700;padding:12px 22px;border-radius:10px;border:0;cursor:pointer;font-size:16px}
.btn:hover{background:var(--accent2);text-decoration:none}
.btn.ghost{background:transparent;color:var(--text);border:1px solid var(--line)}
section{padding:36px 0}
h2{font-size:28px;margin:0 0 16px}
h3{font-size:20px;margin:28px 0 8px}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:16px}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:20px;color:var(--text);display:block}
a.card:hover{border-color:var(--accent);text-decoration:none;transform:translateY(-2px);transition:.15s}
.card h3{margin:0 0 6px;font-size:18px}
.card p{margin:0;color:var(--muted);font-size:15px}
.tag{display:inline-block;font-size:12px;color:var(--accent2);border:1px solid var(--line);border-radius:99px;padding:2px 10px;margin-bottom:10px}
article{padding:36px 0 56px}
article h1{font-size:clamp(28px,4.5vw,40px);line-height:1.2;margin:8px 0 12px}
article .lead{color:var(--muted);font-size:19px;margin-bottom:8px}
article ul,article ol{padding-left:22px}
article li{margin:6px 0}
.crumbs{font-size:14px;color:var(--muted);padding-top:20px}
.crumbs a{color:var(--muted)}
.note{background:rgba(255,138,31,.08);border:1px solid rgba(255,138,31,.35);border-radius:var(--r);padding:14px 18px;margin:18px 0;font-size:16px}
.note.ok{background:rgba(62,207,142,.08);border-color:rgba(62,207,142,.35)}
.code{position:relative;background:var(--bg2);border:1px solid var(--line);border-radius:12px;margin:14px 0}
.code pre{margin:0;padding:16px 90px 16px 16px;overflow:auto;font:14.5px/1.55 ui-monospace,Consolas,Menlo,monospace;white-space:pre-wrap;word-break:break-word}
.copy{position:absolute;top:10px;right:10px;background:var(--card);color:var(--text);border:1px solid var(--line);border-radius:8px;padding:5px 12px;font-size:13px;cursor:pointer}
.copy:hover{border-color:var(--accent)}
.copy.done{color:var(--ok);border-color:var(--ok)}
table{width:100%;border-collapse:collapse;margin:14px 0;font-size:15.5px}
th,td{text-align:left;padding:10px 12px;border-bottom:1px solid var(--line);vertical-align:top}
th{color:var(--muted);font-weight:600;font-size:14px}
.tbl{overflow-x:auto}
.calc{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:22px}
.calc .row{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:14px;margin-bottom:16px}
label{display:block;font-size:14px;color:var(--muted);margin-bottom:6px}
select{width:100%;background:var(--bg2);color:var(--text);border:1px solid var(--line);border-radius:10px;padding:11px;font-size:16px}
#result{margin-top:8px}
details{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:14px 18px;margin:10px 0}
summary{cursor:pointer;font-weight:600}
details p{margin:10px 0 0;color:var(--muted)}
.toc{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:14px 20px;margin:20px 0}
.toc b{display:block;margin-bottom:6px}
.toc ol{margin:0}
footer.site{border-top:1px solid var(--line);padding:30px 0;color:var(--muted);font-size:14px;margin-top:20px}
footer.site .wrap{display:flex;flex-wrap:wrap;gap:12px 28px;justify-content:space-between}
footer.site a{color:var(--muted)}
.ad-slot{display:none}
@media(max-width:700px){
  body{font-size:16px}
  header.site .wrap{height:auto;padding:10px 16px;flex-direction:column;align-items:flex-start;gap:6px}
  .hero{padding:40px 0 24px}
}

/* ---- mobile / app ---- */
html{-webkit-text-size-adjust:100%;text-size-adjust:100%}
a,button,summary,select{touch-action:manipulation;-webkit-tap-highlight-color:rgba(255,138,31,.25)}
body{padding-left:env(safe-area-inset-left);padding-right:env(safe-area-inset-right)}
header.site{padding-top:env(safe-area-inset-top)}
footer.site{padding-bottom:calc(30px + env(safe-area-inset-bottom))}
code{overflow-wrap:anywhere}
.menu-btn{display:none;background:var(--card);color:var(--text);border:1px solid var(--line);border-radius:10px;padding:0 16px;height:44px;font-size:16px;cursor:pointer}
.install{background:var(--accent);color:#1a0f00;font-weight:700;border:0;border-radius:10px;padding:10px 16px;font-size:15px;cursor:pointer;margin-right:12px}
.install[hidden]{display:none}
@media(max-width:700px){
  header.site .wrap{flex-direction:row;flex-wrap:wrap;align-items:center;justify-content:space-between;height:auto;min-height:56px;padding:6px 16px;gap:0}
  .logo{display:flex;align-items:center;min-height:44px}
  .js .menu-btn{display:inline-block}
  .js nav.main{display:none;flex-basis:100%;flex-direction:column;gap:2px;padding:6px 0 10px}
  .js header.site.open nav.main{display:flex}
  nav.main a{display:flex;align-items:center;min-height:46px;padding:0 12px;font-size:17px}
  .hero{padding:32px 0 20px}
  .hero p{font-size:17px}
  .btn{display:inline-flex;align-items:center;justify-content:center;min-height:48px;margin:0 8px 8px 0}
  section{padding:24px 0}
  article{padding:24px 0 40px}
  h2{font-size:24px}
  summary{min-height:44px;display:flex;align-items:center}
  .copy{height:36px;padding:0 14px}
  .code pre{padding-right:100px;font-size:14px}
  select,input[type=text]{min-height:48px;font-size:16px}
  .calc{padding:16px}
  .tbl{margin:0 -16px;padding:0 16px;-webkit-overflow-scrolling:touch}
  table{font-size:15px}
  th,td{padding:9px 8px}
  footer.site .wrap{flex-direction:column}
  footer.site a,.install{display:inline-flex;align-items:center;min-height:44px}
}
@media(display-mode:standalone){
  .install{display:none}
}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}a.card:hover{transform:none;transition:none}}
.logo{display:inline-flex;align-items:center;gap:.28em;white-space:nowrap}
h2,h3{line-height:1.3}
@media(max-width:700px){
  .js header.site.open nav.main{max-height:calc(100vh - 80px);overflow-y:auto}
}

/* figures */
figure.fig{margin:22px 0;background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:16px}
figure.fig svg{display:block;width:100%;max-width:440px;height:auto;margin:0 auto}
figure.fig figcaption{color:var(--muted);font-size:14px;margin-top:12px;line-height:1.5}

/* radar configurator */
.rd-wrap{display:grid;grid-template-columns:minmax(0,1.2fr) minmax(0,1fr);gap:20px;align-items:start}
.rd-screen{position:relative;aspect-ratio:16/9;border-radius:12px;overflow:hidden;border:1px solid var(--line);background:linear-gradient(135deg,#243447,#101820 70%)}
.rd-screen canvas{position:absolute;left:2.5%;top:4%;display:block;aspect-ratio:1/1;height:auto}
.rd-hint{position:absolute;right:10px;bottom:8px;font-size:12px;color:rgba(255,255,255,.55)}
.rd-controls label{display:flex;justify-content:space-between;align-items:center;gap:10px;margin:0 0 4px;color:var(--text);font-size:15px}
.rd-controls label code{font-size:14px}
.rd-controls output{color:var(--accent2);font-weight:700;min-width:3em;text-align:right}
.rd-controls input[type=range]{width:100%;accent-color:var(--accent);margin:0 0 14px;min-height:28px}
.rd-controls .chk{display:flex;align-items:center;gap:10px;min-height:44px;cursor:pointer}
.rd-controls .chk input{width:22px;height:22px;accent-color:var(--accent)}
.rd-presets{display:flex;flex-wrap:wrap;gap:8px;margin:6px 0 10px}
.rd-presets .btn{min-height:44px;font-size:15px;padding:8px 14px}
@media(max-width:800px){.rd-wrap{grid-template-columns:1fr}}
figure.fig img{display:block;width:100%;height:auto;border-radius:10px}
header.site .wrap{height:auto;min-height:60px;padding-top:6px;padding-bottom:6px}
nav.main{justify-content:flex-end}
nav.main a{white-space:nowrap}
.fig-pair{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:22px 0}
.fig-pair figure.fig{margin:0}
@media(max-width:700px){.fig-pair{grid-template-columns:1fr}}