:root{
  --bg:#f5f7fb;--panel:#fff;--panel-soft:#f1f4f8;--text:#172033;--muted:#667085;
  --line:#d9e0ea;--shadow:0 10px 34px rgba(24,35,58,.08);--blue:#3668d8;
  --blue-soft:#e9f0ff;--green:#157a67;--green-soft:#e8f6f2;--gold:#a56a05;
  --gold-soft:#fff4dc;--rose:#b04763;--rose-soft:#fdebf0;--violet:#7252b8;
  --violet-soft:#f1ecff;--ink:#111827
}
html[data-theme="dark"]{
  --bg:#0f131a;--panel:#171c25;--panel-soft:#202631;--text:#f1f4f9;--muted:#a7b1c0;
  --line:#343d4b;--shadow:none;--blue:#8fb2ff;--blue-soft:#213357;--green:#73d3bb;
  --green-soft:#173e37;--gold:#f4c66e;--gold-soft:#443719;--rose:#f0a3b8;
  --rose-soft:#492532;--violet:#c3adff;--violet-soft:#342957;--ink:#f5f7fb
}
@media(prefers-color-scheme:dark){
  html[data-theme="system"]{
    --bg:#0f131a;--panel:#171c25;--panel-soft:#202631;--text:#f1f4f9;--muted:#a7b1c0;
    --line:#343d4b;--shadow:none;--blue:#8fb2ff;--blue-soft:#213357;--green:#73d3bb;
    --green-soft:#173e37;--gold:#f4c66e;--gold-soft:#443719;--rose:#f0a3b8;
    --rose-soft:#492532;--violet:#c3adff;--violet-soft:#342957;--ink:#f5f7fb
  }
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;background:var(--bg);color:var(--text);
  font-family:Inter,ui-sans-serif,-apple-system,BlinkMacSystemFont,"Segoe UI",system-ui,sans-serif;
  font-size:16px;line-height:1.6
}
button,input,select{font:inherit} button{cursor:pointer} a{color:inherit}
.shell{width:min(1220px,calc(100% - 30px));margin:0 auto}
.site-header{padding:30px 0 18px}
.header-row{display:flex;justify-content:space-between;gap:24px;align-items:flex-start}
.kicker,.step-label,.mini-label{
  text-transform:uppercase;letter-spacing:.09em;font-weight:850;color:var(--muted)
}
.kicker{font-size:.78rem}.step-label{font-size:.76rem}.mini-label{font-size:.72rem}
h1{font-size:clamp(2.4rem,5vw,4rem);line-height:.98;letter-spacing:-.05em;margin:.2rem 0 .55rem}
h2{font-size:clamp(1.55rem,2.5vw,2.15rem);line-height:1.12;letter-spacing:-.03em;margin:.15rem 0 .35rem}
h3{font-size:1.08rem;line-height:1.25;letter-spacing:-.015em;margin:.25rem 0 .45rem}
p{margin:.3rem 0}
.hero-copy{max-width:800px;font-size:1.08rem;line-height:1.68;color:var(--muted)}
.header-actions{display:flex;gap:8px;flex-wrap:wrap;justify-content:flex-end}
.button,.select,.text-input{
  min-height:44px;border:1px solid var(--line);border-radius:11px;background:var(--panel);color:var(--text)
}
.button{
  padding:0 14px;font-weight:800;display:inline-flex;align-items:center;justify-content:center;text-decoration:none
}
.button.small{min-height:38px;padding:0 11px;font-size:.8rem}
.button.ghost{background:transparent}.button.primary{background:var(--ink);color:var(--bg);border-color:var(--ink)}
.button.danger{color:var(--rose)}
.select,.text-input{width:100%;padding:0 11px}.select.compact{width:auto;min-width:112px}
.button:hover,.select:hover,.text-input:focus{border-color:var(--blue)}
.progress-rail{
  position:sticky;top:8px;z-index:20;margin:8px 0 28px;padding:8px;border:1px solid var(--line);
  border-radius:14px;background:color-mix(in srgb,var(--panel) 94%,transparent);backdrop-filter:blur(12px);
  display:flex;gap:6px;overflow-x:auto;box-shadow:var(--shadow)
}
.progress-rail a{
  flex:1 0 auto;min-width:120px;text-decoration:none;border-radius:10px;padding:8px 10px;
  color:var(--muted);font-size:.8rem;font-weight:800;display:flex;gap:7px;align-items:center
}
.progress-rail a:hover{background:var(--panel-soft);color:var(--text)}
.progress-rail span{width:25px;height:25px;border-radius:50%;display:grid;place-items:center;background:var(--panel-soft);color:var(--text)}
.section{margin:0 0 38px;scroll-margin-top:90px}
.section-heading{display:flex;justify-content:space-between;gap:18px;align-items:flex-end;margin-bottom:13px}
.section-heading p{color:var(--muted);max-width:780px}
.card{border:1px solid var(--line);background:var(--panel);border-radius:17px;box-shadow:var(--shadow)}
.panel{padding:18px}
.model-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:11px}
.model-card{
  text-align:left;border:1px solid var(--line);border-radius:15px;background:var(--panel);color:var(--text);
  padding:15px;min-height:142px;transition:.15s ease
}
.model-card:hover{transform:translateY(-2px);border-color:var(--blue)}
.model-card.active{border-color:var(--blue);box-shadow:0 0 0 2px color-mix(in srgb,var(--blue) 22%,transparent)}
.model-number{font-size:.72rem;color:var(--muted);font-weight:850}
.model-card strong{display:block;margin-top:10px;font-size:1rem}
.model-card p{color:var(--muted);font-size:.82rem;line-height:1.48;margin-top:4px}
.model-overview{display:grid;grid-template-columns:.9fr 1.1fr;gap:22px;padding:20px;margin-top:14px;align-items:center}
.model-badge{display:inline-flex;padding:5px 9px;border-radius:999px;font-size:.73rem;font-weight:900;background:var(--blue-soft);color:var(--blue)}
.overview-copy>p{color:var(--muted);font-size:.94rem}
.policy-use{display:grid;grid-template-columns:1fr 1fr;gap:9px;margin-top:14px}
.policy-box{border-radius:12px;padding:11px;background:var(--panel-soft);font-size:.82rem}
.policy-box.good{background:var(--green-soft)}.policy-box.caution{background:var(--gold-soft)}
.policy-box strong{display:block;margin-bottom:3px}
.fact-row{display:flex;gap:7px;flex-wrap:wrap;margin-top:12px}
.fact{padding:5px 8px;border:1px solid var(--line);border-radius:999px;font-size:.72rem;color:var(--muted);font-weight:750}
.economy-picture{
  min-height:270px;border-radius:15px;background:
    radial-gradient(circle at 20% 15%,color-mix(in srgb,var(--blue-soft) 90%,transparent),transparent 38%),
    radial-gradient(circle at 83% 84%,color-mix(in srgb,var(--green-soft) 90%,transparent),transparent 38%),
    var(--panel-soft);overflow:hidden;display:grid;place-items:center
}
.economy-picture svg{width:100%;height:270px;display:block}
.story-grid{display:grid;grid-template-columns:230px 1fr;gap:16px;align-items:start}
.story-rail{padding:12px;position:sticky;top:82px}
.story-nav{display:grid;gap:5px;margin-top:8px}
.story-nav button{
  border:0;background:transparent;color:var(--muted);text-align:left;padding:9px;border-radius:9px;font-weight:800
}
.story-nav button:hover{background:var(--panel-soft);color:var(--text)}
.story-main{display:grid;gap:14px}
.notation-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:9px;margin-top:11px}
.notation-card,.glossary-item,.story-step{
  border:1px solid var(--line);border-radius:12px;padding:11px;background:var(--panel-soft)
}
.notation-card strong,.glossary-item strong{display:block}
.notation-card span,.glossary-item p,.story-step p{font-size:.8rem;color:var(--muted);line-height:1.5}
.variable-glossary{display:grid;grid-template-columns:1fr 1fr;gap:9px;margin-top:11px}
.symbol{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;color:var(--blue);font-weight:900}
.flow-story{display:grid;gap:9px;margin-top:11px}
.story-step{display:grid;grid-template-columns:34px 1fr;gap:10px;align-items:start}
.story-step .n{width:30px;height:30px;border-radius:50%;display:grid;place-items:center;background:var(--blue-soft);color:var(--blue);font-weight:900}
.two-col,.script-layout{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.panel-title-row,.code-toolbar{display:flex;justify-content:space-between;gap:12px;align-items:center}
.label-managers{display:grid;gap:13px;margin-top:12px}
.label-group{border:1px solid var(--line);border-radius:13px;padding:12px}
.label-group-head{display:flex;justify-content:space-between;align-items:center;gap:10px}
.label-list{display:flex;gap:7px;flex-wrap:wrap;margin-top:9px}
.label-chip{display:inline-flex;align-items:center;gap:6px;border:1px solid var(--line);border-radius:999px;padding:5px 8px;background:var(--panel-soft);font-size:.8rem}
.add-row{display:flex;gap:7px;margin-top:9px}.add-row .text-input{min-height:38px}
.help{font-size:.82rem;color:var(--muted);line-height:1.55}
.data-choice{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin-top:11px}
.choice-card{border:1px solid var(--line);border-radius:12px;padding:11px;background:transparent;color:var(--text);text-align:left}
.choice-card.active{border-color:var(--blue);background:var(--blue-soft)}
.choice-card strong{display:block;font-size:.88rem}.choice-card span{display:block;font-size:.76rem;color:var(--muted);margin-top:2px}
.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:12px}
.form-field label{display:block;font-size:.78rem;font-weight:800;color:var(--muted);margin-bottom:5px}
.status-pill{white-space:nowrap;padding:6px 9px;border-radius:999px;border:1px solid var(--line);font-size:.76rem;font-weight:850;color:var(--muted)}
.status-pill.ok{color:var(--green);background:var(--green-soft);border-color:transparent}
.status-pill.warn{color:var(--gold);background:var(--gold-soft);border-color:transparent}
.status-pill.bad{color:var(--rose);background:var(--rose-soft);border-color:transparent}
.closure-map{display:grid;grid-template-columns:1fr auto 1fr;gap:12px;align-items:center;margin-top:11px}
.closure-box{background:var(--panel-soft);border-radius:12px;padding:12px}
.closure-arrow{font-weight:900;color:var(--muted)}
.closure-summary{margin-top:12px;padding:11px;border-radius:11px;background:var(--green-soft);color:var(--green);font-size:.84rem;font-weight:750}
.preflight-panel{margin-top:12px}
.check-list{display:grid;gap:7px;margin-top:9px}
.check{display:flex;gap:8px;align-items:flex-start;font-size:.82rem}
.check b{width:22px;height:22px;border-radius:50%;display:grid;place-items:center;background:var(--green-soft);color:var(--green)}
.scenario-layout{display:grid;grid-template-columns:minmax(0,1.28fr) minmax(310px,.72fr);gap:18px;align-items:start}
.quick-actions{display:flex;gap:7px;flex-wrap:wrap;margin:11px 0 13px}
.quick-button{border:1px solid var(--line);border-radius:999px;background:var(--panel-soft);color:var(--text);padding:7px 10px;font-size:.78rem;font-weight:800}
.quick-button:hover{border-color:var(--blue)}
.control-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.control-card{border:1px solid var(--line);border-radius:13px;background:var(--panel);color:var(--text);padding:13px;text-align:left}
.control-card:hover{border-color:var(--blue)}
.control-top{display:flex;justify-content:space-between;gap:8px}
.control-symbol{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:.72rem;color:var(--blue);font-weight:900}
.control-card strong{display:block;font-size:.93rem;margin-top:5px}
.control-card p{font-size:.8rem;color:var(--muted);line-height:1.48;margin-top:3px}
.control-editor{margin-top:14px;border-top:1px solid var(--line);padding-top:14px}
.editor-head{display:flex;justify-content:space-between;gap:8px}
.operation-grid{display:grid;grid-template-columns:1fr 1fr 1fr;gap:9px;margin-top:11px}
.scenario-option{border-left:4px solid var(--blue)}
.scenario-option[data-accent="green"]{border-left-color:var(--green)}
.scenario-option[data-accent="violet"]{border-left-color:var(--violet)}
.scenario-option[data-accent="gold"]{border-left-color:var(--gold)}
.scenario-option[data-accent="rose"]{border-left-color:var(--rose)}
.scenario-stack-panel{position:sticky;top:82px}
.empty-stack{padding:18px 6px;color:var(--muted);font-size:.86rem;text-align:center}
.stack-item{border:1px solid var(--line);border-radius:12px;padding:10px;margin-top:9px}
.stack-item-head{display:flex;justify-content:space-between;gap:8px}
.stack-item strong{font-size:.84rem}.stack-item p{font-size:.77rem;color:var(--muted);line-height:1.45}
.stack-controls{display:flex;gap:4px}.stack-controls button{border:0;background:transparent;color:var(--muted);font-weight:900}
.stack-controls button:hover{color:var(--rose)}
.stack-summary{margin-top:12px;border-top:1px solid var(--line);padding-top:10px;color:var(--muted);font-size:.78rem}
.code-card{overflow:hidden}.code-toolbar{padding:13px 14px;border-bottom:1px solid var(--line)}
.toolbar-buttons{display:flex;gap:6px;flex-wrap:wrap}
pre{margin:0;min-height:420px;max-height:720px;overflow:auto;background:#101723;color:#eaf0fa;padding:17px;font:13px/1.55 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;white-space:pre}
.run-card{align-self:start}.run-steps{counter-reset:run}
.run-step{display:grid;grid-template-columns:28px 1fr;gap:8px;margin-top:11px;align-items:start}
.run-step:before{counter-increment:run;content:counter(run);width:26px;height:26px;border-radius:50%;display:grid;place-items:center;background:var(--panel-soft);font-size:.72rem;font-weight:900}
.command{margin-top:5px;border-radius:8px;padding:7px 8px;background:var(--panel-soft);font:12px/1.45 ui-monospace,SFMono-Regular,Menlo,monospace;overflow-wrap:anywhere}
.divider{height:1px;background:var(--line);margin:15px 0}
.result-files{display:grid;gap:7px;margin-top:9px}.result-file{padding:9px;border-radius:9px;background:var(--panel-soft);font-size:.8rem}
.outputs-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:9px;margin-top:12px}
.output-card{background:var(--panel-soft);border-radius:11px;padding:11px}
.output-card strong{font-size:.84rem}.output-card p{font-size:.77rem;color:var(--muted);line-height:1.45}
.references-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin-top:12px}
.reference-card{border:1px solid var(--line);border-radius:12px;padding:13px}
.reference-card p{font-size:.8rem;color:var(--muted)}.reference-card a{font-size:.78rem;color:var(--blue);font-weight:800}
.reference-tag{font-size:.7rem;color:var(--muted);font-weight:900;text-transform:uppercase;letter-spacing:.07em}
.footer{padding:0 0 40px;text-align:center;color:var(--muted);font-size:.8rem}
.hidden{display:none!important}
@media(max-width:980px){
  .model-grid{grid-template-columns:1fr 1fr}.model-overview,.two-col,.script-layout,.scenario-layout{grid-template-columns:1fr}
  .story-grid{grid-template-columns:1fr}.story-rail,.scenario-stack-panel{position:static}.story-nav{display:flex;overflow:auto}
  .outputs-grid{grid-template-columns:1fr 1fr}.references-grid{grid-template-columns:1fr}.notation-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:650px){
  .shell{width:min(100% - 20px,1220px)}.header-row,.section-heading{flex-direction:column;align-items:flex-start}
  .header-actions{justify-content:flex-start}.model-grid,.control-grid,.form-grid,.operation-grid,.data-choice,.outputs-grid,.variable-glossary,.notation-grid,.policy-use{grid-template-columns:1fr}
  .model-overview{padding:15px}.economy-picture,.economy-picture svg{min-height:240px;height:240px}
}

/* Restored mature closure/preflight presentation */
.contract-title{margin-top:16px}
.contract-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:9px;margin-top:10px}
.contract-card{border:1px solid var(--line);border-radius:12px;padding:11px;background:var(--panel-soft)}
.contract-card strong{display:block;font-size:.82rem;margin-bottom:4px}
.contract-card p{font-size:.78rem;line-height:1.48;color:var(--muted);margin:0}
.contract-card.commitment{background:var(--blue-soft)}
.contract-card.commitment p{color:var(--text)}
.preflight-head{display:flex;justify-content:space-between;gap:14px;align-items:flex-start}
.preflight-note{margin-top:12px;padding:10px 11px;border-left:3px solid var(--gold);border-radius:8px;background:var(--gold-soft);font-size:.8rem;line-height:1.5}
.check.warn b{color:var(--gold);background:var(--gold-soft)}
@media(max-width:980px){.contract-grid{grid-template-columns:1fr 1fr}}
@media(max-width:650px){.contract-grid{grid-template-columns:1fr}.preflight-head{flex-direction:column;align-items:flex-start}}