:root{
  --bg:#FFFFFF; --bg2:#F6F8F9; --bg3:#EEF2F4;
  --ink:#151B20; --ink2:#3D4A52; --muted:#6B7880;
  --rule:#E3E8EB; --rule2:#CBD4D9;
  --accent:#0E7FA6; --accent2:#0A5474; --accent-bg:#E6F2F7;
  --warn:#A2540B; --warn-bg:#FBF3E7; --warn-rule:#E9CFA7;
  --code-bg:#F3F5F7; --deep:#0A5474; --paper:#FFFFFF; --band:#EDF1F3;
  --sans:"Inter",-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  --mono:ui-monospace,"SF Mono",Menlo,Consolas,monospace;
  --sidebar:17rem; --toc:14rem; --measure:46rem;
  --shadow:0 1px 2px rgba(0,0,0,.06),0 8px 24px rgba(0,0,0,.08);
}
[data-theme="dark"]{
  --bg:#0F1519; --bg2:#151C22; --bg3:#1B242B;
  --ink:#E6EBEE; --ink2:#C2CBD1; --muted:#8C9AA3;
  --rule:#243038; --rule2:#31404A;
  --accent:#4FB1D6; --accent2:#8ED0E8; --accent-bg:#122A36;
  --warn:#E5A15B; --warn-bg:#2A1F12; --warn-rule:#4B3520;
  --code-bg:#151C22; --deep:#8ED0E8; --paper:#0F1519; --band:#161E25;
  --shadow:0 1px 2px rgba(0,0,0,.5),0 8px 24px rgba(0,0,0,.45);
}
@media (prefers-color-scheme:dark){
  :root:not([data-theme="light"]){
    --bg:#0F1519; --bg2:#151C22; --bg3:#1B242B;
    --ink:#E6EBEE; --ink2:#C2CBD1; --muted:#8C9AA3;
    --rule:#243038; --rule2:#31404A;
    --accent:#4FB1D6; --accent2:#8ED0E8; --accent-bg:#122A36;
    --warn:#E5A15B; --warn-bg:#2A1F12; --warn-rule:#4B3520;
    --code-bg:#151C22; --deep:#8ED0E8; --paper:#0F1519; --band:#161E25;
    --shadow:0 1px 2px rgba(0,0,0,.5),0 8px 24px rgba(0,0,0,.45);
  }
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--sans);font-size:16px;line-height:1.65;
  -webkit-font-smoothing:antialiased}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline;text-underline-offset:.18em}
.skip{position:absolute;left:-999px;top:0;background:var(--accent);color:#fff;padding:.5rem .8rem;z-index:100}
.skip:focus{left:.5rem;top:.5rem}
kbd{font:600 .7rem var(--sans);color:var(--muted);border:1px solid var(--rule2);border-radius:4px;padding:.05rem .35rem;background:var(--bg)}

/* ---------- top bar (mobile) ---------- */
.topbar{display:none;position:sticky;top:0;z-index:40;height:3.25rem;align-items:center;gap:.5rem;
  padding:0 .75rem;background:var(--bg);border-bottom:1px solid var(--rule)}
.topbar .spacer{flex:1}
.topbar button{appearance:none;border:0;background:transparent;color:var(--ink2);width:2.4rem;height:2.4rem;
  border-radius:8px;display:grid;place-items:center;cursor:pointer}
.topbar button:hover{background:var(--bg3)}
.brand{display:inline-flex;align-items:center;gap:.55rem;font-weight:700;color:var(--ink);letter-spacing:-.01em}
.brand:hover{text-decoration:none}
.brand .mark{display:inline-grid;place-items:center;width:1.6rem;height:1.6rem;border-radius:6px;background:var(--accent);
  color:#fff;font-size:.9rem;font-weight:700}
.brand small{display:block;font-weight:400;font-size:.72rem;color:var(--muted);margin-top:.05rem}
.brand.side{flex-direction:row;align-items:center;padding:1.1rem 1.25rem .9rem;font-size:1.05rem}
.brand.side .mark{width:1.9rem;height:1.9rem;font-size:1.05rem;border-radius:7px}
.theme .moon{display:none}
[data-theme="dark"] .theme .sun{display:none}
[data-theme="dark"] .theme .moon{display:block}
@media (prefers-color-scheme:dark){
  :root:not([data-theme="light"]) .theme .sun{display:none}
  :root:not([data-theme="light"]) .theme .moon{display:block}
}

/* ---------- layout ---------- */
.layout{display:grid;grid-template-columns:var(--sidebar) minmax(0,1fr) var(--toc);min-height:100vh}
.sidebar{position:sticky;top:0;height:100vh;overflow-y:auto;border-right:1px solid var(--rule);background:var(--bg2);
  display:flex;flex-direction:column;scrollbar-width:thin}
.sidenav{padding:.25rem .75rem 1rem;flex:1}
.sidenav a{display:block;padding:.42rem .55rem;border-radius:7px;color:var(--ink2);font-size:.92rem;font-weight:500}
.sidenav a:hover{background:var(--bg3);text-decoration:none;color:var(--ink)}
.sidenav a.active{background:var(--accent-bg);color:var(--accent2);font-weight:600}
.sidenav .subnav{margin:.1rem 0 .35rem .7rem;padding-left:.55rem;border-left:1px solid var(--rule2)}
.sidenav .subnav a{font-size:.87rem;font-weight:400;padding:.34rem .55rem}
.side-foot{padding:.9rem 1.25rem 1.1rem;border-top:1px solid var(--rule);font-size:.8rem;color:var(--muted);
  display:flex;justify-content:space-between;align-items:center}
.scrim{display:none}

.search{position:relative;padding:0 .95rem .6rem}
.search input{width:100%;padding:.55rem 2.4rem .55rem .8rem;border:1px solid var(--rule2);border-radius:8px;
  background:var(--bg);color:var(--ink);font:inherit;font-size:.9rem;outline:none}
.search input:focus{border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-bg)}
.search kbd{position:absolute;right:1.6rem;top:.55rem}
.results{position:absolute;left:.95rem;right:.95rem;top:2.9rem;z-index:30;background:var(--bg);border:1px solid var(--rule2);
  border-radius:10px;box-shadow:var(--shadow);max-height:22rem;overflow:auto;padding:.35rem}
.results a{display:block;padding:.5rem .6rem;border-radius:7px;color:var(--ink)}
.results a:hover,.results a.sel{background:var(--bg3);text-decoration:none}
.results b{display:block;font-size:.88rem;font-weight:600}
.results span{display:block;font-size:.78rem;color:var(--muted);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.results .none{padding:.6rem;color:var(--muted);font-size:.85rem}

.content{padding:2.6rem 3.25rem 4rem;min-width:0}
.doc{max-width:var(--measure)}
.toc{position:sticky;top:0;height:100vh;overflow-y:auto;padding:2.9rem 1.25rem 2rem 0;font-size:.82rem;scrollbar-width:thin}
.toc-t{font-weight:600;color:var(--muted);text-transform:uppercase;letter-spacing:.06em;font-size:.68rem;margin:0 0 .5rem .75rem}
.toc a{display:block;padding:.26rem .75rem;color:var(--muted);border-left:2px solid var(--rule);line-height:1.35}
.toc a.h3{padding-left:1.5rem}
.toc a:hover{color:var(--ink);text-decoration:none}
.toc a.cur{color:var(--accent2);border-left-color:var(--accent);font-weight:600}

/* ---------- typography ---------- */
h1{font-size:2.15rem;line-height:1.15;letter-spacing:-.02em;margin:0 0 1.1rem;font-weight:700}
h2{font-size:1.4rem;line-height:1.25;letter-spacing:-.01em;margin:2.4rem 0 .8rem;padding-top:.4rem;font-weight:700;
  scroll-margin-top:1.5rem}
h3{font-size:1.08rem;margin:1.8rem 0 .5rem;font-weight:600;color:var(--accent2);scroll-margin-top:1.5rem}
h4{font-size:.95rem;margin:1.4rem 0 .4rem;font-weight:600}
p{margin:0 0 1rem}
.col p:last-child{margin-bottom:0}
.col{margin-bottom:1.25rem}
.src{font-size:.86rem;color:var(--muted);margin:-.3rem 0 .9rem}
.note{font-size:.9rem;color:var(--ink2);border-left:3px solid var(--rule2);padding:.2rem 0 .2rem .9rem;margin:1rem 0 1.4rem}
b,strong{font-weight:600}
ol{padding-left:1.4rem}
ol li{margin:.3rem 0}

.spine{display:flex;flex-wrap:wrap;gap:.5rem;margin:.5rem 0 1.6rem}
.spine div{flex:1 1 6.2rem;min-width:6.2rem;background:var(--bg2);border:1px solid var(--rule);border-radius:9px;
  padding:.6rem .65rem;font-size:.82rem;color:var(--ink);font-weight:600;line-height:1.25}
.spine b{display:block;font-size:1.5rem;font-weight:700;color:var(--accent);line-height:1;margin-bottom:.2rem}
.spine span{display:block;margin-top:.2rem;font-weight:400;font-size:.74rem;color:var(--muted);font-style:italic}
.home h1{font-size:2.9rem}
.home .doc > .col:first-of-type p:first-child{font-size:1.15rem;color:var(--ink2);line-height:1.55}

/* ---------- figures ---------- */
figure{margin:1.4rem 0 1.6rem}
figure img,figure svg{max-width:100%;height:auto;display:block;border-radius:6px}
figure.mine svg{width:100%}
figure.medium img{max-width:34rem}
figure.narrow img{max-width:24rem}
figure.marker img{max-width:20rem}
figcaption{font-size:.84rem;color:var(--muted);margin-top:.55rem;line-height:1.45}
figcaption b{color:var(--ink2)}
.lifecycle.stacked{display:none}
@media (max-width:640px){.lifecycle.wide{display:none}.lifecycle.stacked{display:block}}

/* ---------- tables ---------- */
.tablewrap{overflow-x:auto;margin:1rem 0 1.5rem;border:1px solid var(--rule);border-radius:9px}
table{border-collapse:collapse;width:100%;font-size:.9rem}
th{background:var(--bg2);text-align:left;padding:.6rem .8rem;font-weight:600;font-size:.8rem;color:var(--ink2);
  border-bottom:1px solid var(--rule);white-space:nowrap}
td{padding:.6rem .8rem;border-bottom:1px solid var(--rule);vertical-align:top}
tr:last-child td{border-bottom:0}
td:first-child{font-weight:600;color:var(--accent2)}
table.cl td:first-child{width:2.6rem;color:var(--muted);font-weight:500;font-variant-numeric:tabular-nums}
.check h4{margin-top:1.3rem}

/* ---------- callouts ---------- */
.gates{display:grid;grid-template-columns:1fr 1fr;gap:.6rem;margin:0 0 1.3rem}
.gates div{background:var(--bg2);border:1px solid var(--rule);border-radius:9px;padding:.7rem .9rem;font-size:.9rem}
.gates b{display:block;font-size:.68rem;letter-spacing:.08em;text-transform:uppercase;color:var(--muted);margin-bottom:.25rem}
.caution{background:var(--warn-bg);border:1px solid var(--warn-rule);border-left:4px solid var(--warn);border-radius:8px;
  padding:.85rem 1rem .6rem;margin:1.1rem 0 1.5rem;font-size:.92rem}
.caution b{display:block;color:var(--warn);margin-bottom:.35rem;font-size:.86rem}
.caution ul{margin:0;padding-left:1.15rem}
.caution li{margin:.3rem 0}
.story{background:var(--bg2);border:1px solid var(--rule);border-radius:9px;padding:1rem 1.15rem;margin:1.2rem 0 1.5rem}
.story h4{margin-top:0}
.story p:last-child{margin-bottom:0}

/* ---------- templates ---------- */
.tpl{margin:1.2rem 0 1.6rem;border:1px solid var(--rule);border-radius:9px;overflow:hidden}
.tplhead{display:flex;align-items:center;justify-content:space-between;gap:1rem;padding:.55rem .55rem .55rem 1rem;
  background:var(--bg2);border-bottom:1px solid var(--rule)}
.tplhead h4{margin:0;font-size:.92rem}
.copy{appearance:none;font:600 .78rem var(--sans);color:var(--accent2);background:var(--bg);border:1px solid var(--rule2);
  border-radius:6px;padding:.35rem .7rem;cursor:pointer}
.copy:hover{border-color:var(--accent)}
.tpl pre{margin:0;padding:1rem 1.1rem;background:var(--code-bg);font:.82rem/1.55 var(--mono);color:var(--ink);overflow-x:auto;
  white-space:pre}

/* ---------- prev / next, footer ---------- */
.pnbar{display:grid;grid-template-columns:1fr 1fr;gap:.75rem;margin:3rem 0 0;padding-top:1.5rem;border-top:1px solid var(--rule)}
.pn{display:block;padding:.85rem 1rem;border:1px solid var(--rule);border-radius:10px;color:var(--ink);font-weight:600;font-size:.95rem}
.pn:hover{border-color:var(--accent);text-decoration:none}
.pn span{display:block;font-size:.72rem;color:var(--muted);font-weight:500;margin-bottom:.15rem}
.pn.next{text-align:right}
.foot{max-width:var(--measure);margin:2.5rem 0 0;padding-top:1.2rem;border-top:1px solid var(--rule);font-size:.78rem;
  color:var(--muted);line-height:1.5}

/* ---------- responsive ---------- */
@media (max-width:1180px){.layout{grid-template-columns:var(--sidebar) minmax(0,1fr)}.toc{display:none}}
@media (max-width:860px){
  .topbar{display:flex}
  .layout{grid-template-columns:minmax(0,1fr)}
  .sidebar{position:fixed;left:0;top:0;bottom:0;width:min(20rem,86vw);z-index:60;transform:translateX(-100%);
    transition:transform .22s ease;box-shadow:none}
  body.nav-open .sidebar{transform:none;box-shadow:var(--shadow)}
  .scrim{display:block;position:fixed;inset:0;background:rgba(0,0,0,.35);z-index:55;opacity:0;pointer-events:none;transition:opacity .2s}
  body.nav-open .scrim{opacity:1;pointer-events:auto}
  .content{padding:1.5rem 1.15rem 3rem}
  h1{font-size:1.75rem}.home h1{font-size:2.2rem}
  h2{font-size:1.22rem}
  .gates{grid-template-columns:1fr}
  .pnbar{grid-template-columns:1fr}
  .pn.next{text-align:left}
  .search kbd{display:none}
}

.tagline{font-size:1.2rem;color:var(--muted);margin:-.4rem 0 1.3rem}
.cta{display:flex;flex-wrap:wrap;gap:.6rem;margin:1.6rem 0 .5rem}
.btn{display:inline-block;padding:.65rem 1.1rem;border:1px solid var(--rule2);border-radius:9px;font-weight:600;
  font-size:.92rem;color:var(--ink)}
.btn:hover{border-color:var(--accent);text-decoration:none}
.btn.primary{background:var(--accent);border-color:var(--accent);color:#fff}
.btn.primary:hover{background:var(--accent2);border-color:var(--accent2)}

/* ---------- inline lifecycle diagram ---------- */
svg.lifecycle{display:block;width:100%;height:auto}
svg.lifecycle.stacked{max-width:22rem;margin:0 auto}
svg .band{fill:var(--band);stroke:var(--rule)}
svg .bandlbl{fill:var(--muted);font-family:var(--sans);font-size:13px;font-weight:600}
svg .wp{fill:var(--accent)}
svg .wplbl{fill:#fff;font-family:var(--sans);font-size:14px;font-weight:600;text-anchor:middle}
svg .ring-a{fill:var(--deep)}
svg .ring-b{fill:var(--accent)}
[data-theme="dark"] svg .ring-a{fill:#0A5474}
[data-theme="dark"] svg .ring-b{fill:#0E7FA6}
[data-theme="dark"] svg .wp{fill:#0E7FA6}
svg .ringlbl{fill:#fff;font-family:var(--sans);font-size:12px;font-weight:600;text-anchor:middle}
svg .holelbl{fill:var(--ink);font-family:var(--sans);font-size:11.5px;font-weight:600;text-anchor:middle}
svg .looplbl{fill:var(--muted);font-family:var(--sans);font-size:12px;text-anchor:middle}
svg .gate{fill:var(--ink);font-family:var(--sans);font-size:11px;text-anchor:middle}
svg .gate.small{fill:var(--muted);font-size:10px}
svg .badge{fill:var(--paper);stroke:var(--rule2);stroke-width:1}
svg .conn{stroke:var(--accent);stroke-width:2.5}
svg .mk{fill:var(--accent)}
svg .mkd{fill:var(--muted)}
svg .iter,svg .iter-s{fill:none;stroke:var(--accent);stroke-width:2}
svg .fb{fill:none;stroke:var(--muted);stroke-width:1.5;stroke-dasharray:5 4}
svg .fb-lbl{fill:var(--muted);font-family:var(--sans);font-size:12px;text-anchor:middle}
svg .loopbox{fill:none;stroke:var(--rule2);stroke-width:1;stroke-dasharray:3 3}
svg .hole{fill:var(--paper)}
@media (prefers-color-scheme:dark){
  :root:not([data-theme="light"]) svg .ring-a{fill:#0A5474}
  :root:not([data-theme="light"]) svg .ring-b{fill:#0E7FA6}
  :root:not([data-theme="light"]) svg .wp{fill:#0E7FA6}
}

.side-foot .theme{appearance:none;border:1px solid var(--rule2);background:var(--bg);color:var(--ink2);width:2rem;height:2rem;
  border-radius:7px;display:grid;place-items:center;cursor:pointer;margin-left:auto}
.side-foot{gap:.75rem}
.source{font-size:.9rem;color:var(--muted);margin:1.1rem 0 0}
.hero-diagram{margin:1.4rem 0 1.8rem}
.hero-diagram > a{display:block}
.hero-diagram img{width:100%;height:auto;border-radius:10px;border:1px solid var(--rule);box-shadow:var(--shadow);background:#F7F8FA}
.hero-diagram figcaption{margin-top:.6rem}