@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Sans:wght@400;500;600;700&family=IBM+Plex+Sans+Thai:wght@400;500;600;700&family=IBM+Plex+Mono:wght@400;500&family=Noto+Sans+SC:wght@400;500;700&display=swap');

:root{
 --paper:#e9eae7;--panel:#f5f5f2;--ink:#191c1b;--muted:#585e5b;--line:#c6cbc6;
 --accent:#f59e0b;--dark:#111416;--dim:#a2aca9;
 --s:12px;--m:16px;--l:30px;
 --sans:'IBM Plex Sans','IBM Plex Sans Thai','Noto Sans SC',Arial,sans-serif;
 --mono:'IBM Plex Mono',ui-monospace,monospace;
}
html[lang^="th"] body{--sans:'IBM Plex Sans Thai','IBM Plex Sans',Arial,sans-serif;line-height:1.75}
html[lang^="zh"] body{--sans:'Noto Sans SC','IBM Plex Sans',Arial,sans-serif;line-height:1.8}

*{box-sizing:border-box}
body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--sans);font-size:var(--m);line-height:1.5}
button,input,select{font:inherit}
button,select{min-height:44px}
button{border:1px solid var(--line);background:transparent;color:inherit;padding:8px 14px;cursor:pointer;transition:background .16s ease-out,transform .16s ease-out}
button:hover{background:var(--line)}
button:active{transform:scale(.97)}
button:disabled{cursor:not-allowed;opacity:.5}
button:focus-visible,select:focus-visible,input:focus-visible,a:focus-visible,canvas:focus-visible,summary:focus-visible{outline:2px solid var(--accent);outline-offset:3px}
.primary{background:var(--accent);border-color:var(--accent);color:var(--ink);font-weight:600}
.primary:hover{background:#eab046}
h1,h2,h3{font-weight:600;margin:0}
h1{font-size:var(--l);line-height:1.15}
p{margin:0 0 12px}
a{color:inherit}

/* ── header ───────────────────────────────────────────────────────────── */
header{min-height:72px;padding:10px 28px;border-bottom:2px solid var(--ink);display:flex;align-items:center;gap:28px}
.brand{font-weight:700;font-size:var(--l);text-decoration:none;white-space:nowrap;letter-spacing:-1px}
.brand span{color:var(--accent);letter-spacing:-.03em}
.tabs{display:flex;gap:0;border:1px solid var(--ink)}
.tabs button{border:0;padding:8px 18px;min-height:44px;font-size:var(--s);text-transform:uppercase;letter-spacing:.1em;color:var(--muted)}
.tabs button+button{border-left:1px solid var(--ink)}
.tabs button.on{background:var(--ink);color:var(--paper)}
.langs{margin-left:auto;display:flex;border:1px solid var(--ink)}
.langs button{border:0;border-left:1px solid var(--line);padding:6px 14px;min-height:38px;font-size:var(--s);font-family:var(--mono)}
.langs button:first-child{border-left:0}
.langs button[aria-pressed="true"]{background:var(--accent);color:var(--ink);font-weight:500}

main{max-width:1800px;margin:auto;padding:0 28px}
.tabpane{display:none}
.tabpane.on{display:block}

/* ── titlebar ─────────────────────────────────────────────────────────── */
.titlebar{display:flex;align-items:center;justify-content:space-between;padding:25px 0 23px;gap:16px}
.eyebrow{font-size:var(--s);text-transform:uppercase;letter-spacing:.12em;margin:0 0 6px;color:var(--muted)}
.actions{display:flex;gap:8px}

/* ── studio grid ──────────────────────────────────────────────────────── */
.studio{display:grid;grid-template-columns:270px minmax(300px,1fr) 320px;border-top:2px solid var(--ink);border-bottom:2px solid var(--ink);background:var(--panel)}
.controls{padding:18px 20px;border-right:1px solid var(--line)}
.railheading{display:flex;justify-content:space-between;align-items:center;margin-bottom:16px}
.railheading h2{font-size:var(--m)}
.data,dd,.control output,.viewhead,.viewfoot,.planhead output{font-family:var(--mono);font-size:var(--s)}
.note{color:var(--muted);font-size:var(--s);margin:0 0 10px;line-height:1.45}
.splitter{height:2px;background:var(--ink);margin:16px 0}
.ctl{display:block;font-size:var(--s);text-transform:uppercase;letter-spacing:.08em;color:var(--muted);margin:14px 0 6px}
select{width:100%;padding:8px 10px;border:1px solid var(--ink);background:var(--paper);color:var(--ink);margin-bottom:10px;font-size:var(--s)}
details{border-top:1px solid var(--line);margin-top:14px;padding-top:10px}
summary{cursor:pointer;font-size:var(--s);text-transform:uppercase;letter-spacing:.08em;padding:6px 0;color:var(--muted)}
.control{margin:10px 0}
.controlhead{display:flex;justify-content:space-between;align-items:baseline;gap:8px}
.controlhead label{font-size:var(--s)}
input[type=range]{width:100%;accent-color:var(--accent)}
.knowledgebutton{width:100%;font-size:var(--s);text-align:left;margin-top:14px;border-color:var(--ink)}

/* ── viewport ─────────────────────────────────────────────────────────── */
.viewport{position:relative;background:var(--dark);min-height:700px;overflow:hidden}
.viewhead{position:absolute;top:14px;left:20px;right:20px;display:flex;justify-content:space-between;color:var(--dim);z-index:2;pointer-events:none}
.square{display:inline-block;width:8px;height:8px;background:var(--accent);margin-right:8px}
/* The canvas is out of flow on purpose: writing its backing store must never be
   able to resize its own container, or resize → draw → resize never settles. */
canvas{position:absolute;inset:0;width:100%;height:100%;display:block;touch-action:none}
.viewtools{position:absolute;top:46px;right:20px;display:flex;flex-direction:column;gap:6px;z-index:2}
.viewtools button{background:#1b2124dd;color:var(--dim);border-color:#3a454a;font-size:var(--s);padding:6px 10px;min-height:36px}
.viewtools button:hover{background:#2b3438;color:#fff}
.viewfoot{position:absolute;bottom:14px;left:20px;right:20px;display:flex;justify-content:space-between;color:var(--dim);pointer-events:none}
.model-stamp{position:absolute;bottom:48px;left:22px;color:var(--dim);font-family:var(--mono);font-size:34px;line-height:.92;letter-spacing:-.02em;pointer-events:none}
.model-stamp span{color:var(--accent)}

/* ── results ──────────────────────────────────────────────────────────── */
.results{padding:18px 20px;border-left:1px solid var(--line)}
.primarymetric{border-top:2px solid var(--ink);border-bottom:2px solid var(--ink);padding:12px 0;margin:8px 0 14px}
.primarymetric p{margin:0;font-size:var(--s);color:var(--muted)}
.primarymetric strong{font-size:var(--l);font-family:var(--mono);display:block;line-height:1.2}
.primarymetric #delta{font-size:var(--s);color:var(--muted);margin-top:6px}
.metrics{margin:0 0 12px}
.metrics>div{display:flex;justify-content:space-between;gap:10px;padding:5px 0;border-bottom:1px solid var(--line)}
.metrics dt{font-size:var(--s);color:var(--muted)}
.metrics dd{margin:0;font-size:var(--s);text-align:right;white-space:nowrap}
/* Derived rows are separated from the chosen assumptions above them: these
   numbers follow from geometry, the others are inputs the reader can change. */
.metrics .derived{border-bottom:1px dotted var(--line)}
.metrics .derived dt{color:var(--ink)}
.metrics .derived dd{font-family:var(--mono);color:var(--accent)}
.metrics .tag{display:inline-block;margin-left:6px;padding:1px 4px;border:1px solid var(--line);
 font-family:var(--mono);font-size:10px;line-height:1.4;letter-spacing:.04em;text-transform:uppercase;
 color:var(--muted);vertical-align:1px}
#feasibility{font-size:var(--s);padding:9px 11px;border:1px solid var(--ink);margin-bottom:16px}
#feasibility.valid{background:#e6ebe4}
#feasibility.invalid{background:var(--accent)}

#premiumPanel{border-top:1px solid var(--line);padding-top:12px;margin-bottom:16px}
.panelh{font-size:var(--s);text-transform:uppercase;letter-spacing:.08em;color:var(--muted);margin-bottom:10px}
.bar{display:grid;grid-template-columns:1fr auto;gap:4px;font-size:var(--s);margin-bottom:8px}
.bar .track{grid-column:1/-1;height:7px;background:var(--line)}
.bar .fill{height:100%;background:var(--ink)}
.bar.neg .fill{background:var(--accent)}
.bar span:last-child{font-family:var(--mono)}

.planhead{display:flex;justify-content:space-between;align-items:baseline;border-top:2px solid var(--ink);padding-top:12px;margin-top:4px}
.planhead label{font-size:var(--s);color:var(--muted)}
#plan{width:100%;height:230px;display:block;margin:8px 0}
.legend{display:flex;gap:14px;font-size:var(--s);color:var(--muted)}
.legend i{display:inline-block;width:10px;height:10px;margin-right:6px;border:1px solid var(--ink)}
.legend i.corner{background:var(--accent)}
.legend i.core{background:#5b6160;border-style:double;border-width:3px}

/* ── explore ──────────────────────────────────────────────────────────── */
.explore{padding:30px 0;border-bottom:2px solid var(--ink)}
.explorehead{display:flex;justify-content:space-between;align-items:flex-end;gap:24px;margin-bottom:20px;flex-wrap:wrap}
.explorehead h2{font-size:22px}
.explorehead p{margin:6px 0 0;color:var(--muted);font-size:var(--s)}
.searchcontrols{display:flex;gap:8px;align-items:center}
.searchcontrols select{width:auto;margin:0;min-width:240px}
.empty{border:1px dashed var(--line);padding:26px;display:flex;gap:18px;align-items:center;color:var(--muted);font-size:var(--s);position:relative;overflow:hidden}
.empty p{margin:0}
.empty .data{font-size:var(--l);color:var(--accent);font-family:var(--mono)}
.empty::after{content:'';position:absolute;left:0;bottom:0;height:2px;width:var(--done,0%);background:var(--accent);transition:width .12s linear}
.tablewrap{overflow-x:auto}
table{border-collapse:collapse;width:100%;font-size:var(--s)}
th{text-align:left;border-bottom:2px solid var(--ink);padding:8px 10px;text-transform:uppercase;letter-spacing:.07em;font-weight:600;font-size:11px}
td{padding:9px 10px;border-bottom:1px solid var(--line)}
td.numeric{font-family:var(--mono);text-align:right;white-space:nowrap}
tbody tr:hover{background:var(--panel)}
.searchsummary{font-size:var(--s);color:var(--muted);margin-top:12px}
.win{background:var(--accent)}

/* ── studies ──────────────────────────────────────────────────────────── */
.studies{padding:26px 0;display:grid;grid-template-columns:270px 1fr;gap:28px}
.studies p{margin:6px 0 0;color:var(--muted);font-size:var(--s)}
#savedStudies{display:flex;flex-wrap:wrap;gap:8px;align-items:flex-start}
.saved{display:flex;border:1px solid var(--ink)}
.saved button{border:0;font-size:var(--s)}
.saved button:last-child{border-left:1px solid var(--line);padding:8px 12px}

/* ── research ─────────────────────────────────────────────────────────── */
.researchhead{padding:34px 0 30px;border-bottom:2px solid var(--ink)}
.researchhead h1{max-width:20ch;font-size:38px;margin-bottom:18px}
.lede{font-size:20px;line-height:1.5;max-width:62ch;color:var(--ink)}
.credit{font-size:var(--s);color:var(--muted);max-width:74ch;border-left:2px solid var(--accent);padding-left:14px;margin-top:20px}
#rBody{max-width:1000px}
#rBody section{padding:30px 0;border-bottom:1px solid var(--line)}
#rBody h2{font-size:21px;margin-bottom:14px;letter-spacing:-.01em}
#rBody p{max-width:74ch;line-height:1.65}
#rBody pre{background:var(--dark);color:#c9d3d0;padding:18px 20px;overflow-x:auto;font-family:var(--mono);font-size:12.5px;line-height:1.7;border-left:2px solid var(--accent);margin:0 0 16px}
#rBody .note{border-left:2px solid var(--line);padding-left:14px;max-width:74ch}
#rBody .note.credit{border-left-color:var(--accent)}
.rtable{margin:0 0 18px}
.rtable td{vertical-align:top}
.rtable td:first-child{width:26%;font-weight:600}
.rtable td:nth-child(2){width:56%}
.rtable td:last-child{width:18%}
.rtable .ctl-tag{font-family:var(--mono);font-size:11px;text-transform:uppercase;letter-spacing:.07em;color:var(--ink);background:var(--accent);padding:3px 7px;white-space:nowrap}
.regimecards{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:1px;background:var(--line);border:1px solid var(--ink);margin-bottom:18px}
.regimecards div{background:var(--panel);padding:14px}
.regimecards h4{margin:0 0 6px;font-size:var(--s);text-transform:uppercase;letter-spacing:.08em}
.regimecards .reads{font-family:var(--mono);font-size:11px;color:var(--accent);display:block;margin-bottom:8px}
.regimecards p{font-size:var(--s);margin:0;color:var(--muted)}
.verdict{font-size:var(--s);padding:12px 14px;background:var(--panel);border-left:2px solid var(--ink);margin:0 0 18px}
.srcnote{font-size:var(--s);color:var(--muted);padding:22px 0;border-top:2px solid var(--ink);margin-top:10px;max-width:74ch}

/* ── dialogs ──────────────────────────────────────────────────────────── */
dialog{border:2px solid var(--ink);background:var(--paper);color:var(--ink);padding:30px;max-width:min(720px,92vw);max-height:86vh;overflow:auto}
dialog::backdrop{background:#0d1112cc}
dialog .close{position:absolute;top:10px;right:10px;border:0;font-size:20px;padding:6px 12px}
dialog h2{margin-bottom:14px}
dialog h3{margin:22px 0 8px;font-size:var(--s);text-transform:uppercase;letter-spacing:.08em;color:var(--muted)}
dialog p{font-size:var(--s);line-height:1.6}
dialog ul{padding-left:20px;font-size:var(--s)}
dialog li{margin:7px 0;line-height:1.5}
.exportoptions{display:flex;flex-wrap:wrap;gap:8px;margin:18px 0}
#knowledgeContent table{table-layout:auto}
#knowledgeContent td,#knowledgeContent th{padding:8px 8px}
.knowledgeDownloads{display:flex;flex-wrap:wrap;gap:12px;font-size:var(--s)}
.knowledgeDownloads a{min-height:44px;display:inline-flex;align-items:center}
#toast{position:fixed;bottom:20px;left:50%;transform:translateX(-50%);background:var(--ink);color:var(--paper);padding:11px 18px;font-size:var(--s);opacity:0;pointer-events:none;transition:opacity .2s;z-index:50;max-width:90vw}
#toast.on{opacity:1}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}

/* ── responsive ───────────────────────────────────────────────────────── */
@media(min-width:1550px){.studio{grid-template-columns:300px 1fr 350px}.viewport{min-height:780px}}
@media(max-width:1180px){
 header{padding:10px 18px;gap:18px}
 main{padding:0 18px}
 .studio{grid-template-columns:250px 1fr}
 .results{grid-column:1/-1;border-left:0;border-top:2px solid var(--ink);display:grid;grid-template-columns:1fr 1fr;gap:0 32px;padding:18px 20px}
 .results>.railheading,.results>.note{grid-column:1}
 .primarymetric{grid-column:1;grid-row:3}
 .metrics{grid-column:1;grid-row:4/10}
 #premiumPanel{grid-column:1;grid-row:10}
 .planhead{grid-column:2;grid-row:1;border-top:0;padding:0}
 .results>#floor{grid-column:2;grid-row:2}
 .results>#plan{grid-column:2;grid-row:3/6;height:250px}
 .legend{grid-column:2;grid-row:6}
 #floorStats{grid-column:2;grid-row:7}
 #feasibility{grid-column:1/-1;grid-row:11}
 .viewport{min-height:680px}
 .explorehead{align-items:flex-start;flex-direction:column}
 .studies{grid-template-columns:1fr}
 .researchhead h1{font-size:30px}
 .lede{font-size:18px}
}
@media(max-width:680px){
 header{padding:10px 12px;gap:10px;min-height:64px;flex-wrap:wrap}
 .brand{font-size:var(--m);letter-spacing:0}
 .tabs button{padding:8px 12px;font-size:11px}
 .langs button{padding:6px 10px}
 main{padding:0 12px}
 .titlebar{padding:20px 0;display:block}
 .actions{margin-top:16px}
 .studio{display:flex;flex-direction:column}
 .viewport{order:0;min-height:520px}
 .controls{order:1;border-right:0;border-top:2px solid var(--ink)}
 .results{order:2;display:block}
 .controls #geometryControls{display:grid;grid-template-columns:1fr 1fr;gap:0 20px}
 .results #plan{height:240px}
 .planhead{border-top:2px solid var(--ink);padding-top:16px;margin-top:12px}
 .primarymetric strong{font-size:var(--l)}
 .searchcontrols{width:100%;flex-direction:column}
 .searchcontrols select{width:100%;min-width:0}
 .searchcontrols button{width:100%}
 .researchhead h1{font-size:24px}
 .lede{font-size:16px}
 .rtable td:first-child,.rtable td:nth-child(2),.rtable td:last-child{width:auto;display:block;border:0}
 .rtable td:first-child{border-bottom:2px solid var(--ink);padding-bottom:4px}
 .rtable tr{display:block;padding:12px 0;border-bottom:1px solid var(--line)}
 .model-stamp{font-size:24px;bottom:120px;left:16px}
 .viewhead,.viewfoot{left:16px;right:16px}
 dialog{padding:22px 18px}
}
@media(prefers-reduced-motion:reduce){*{transition:none!important}}