/* Shared styles for every page under /lab/ */
:root{
  --bg:#f7f6f2; --surface:#ffffff; --ink:#1b1f24; --muted:#5b6470; --line:#e3e1da;
  --accent:#0f3d6e; --accent-ink:#ffffff; --accent-soft:#e6eef7; --code-bg:#efede6;
  --ok-bg:#e3f4e8; --ok-ink:#1d6b38; --ok-line:#8fcca3; --bad-bg:#fbe9e7; --bad-ink:#a3362b; --bad-line:#e3a59d;
}
:root{color-scheme:light}
:root[data-theme="dark"]{--bg:#111418;--surface:#181c21;--ink:#e8eaed;--muted:#9aa3ad;--line:#2a3038;--accent:#7fb2ea;--accent-ink:#0d1520;--accent-soft:#1a2633;--code-bg:#1b2027;--ok-bg:#173323;--ok-ink:#7fd39b;--ok-line:#2f6b45;--bad-bg:#3a1d1a;--bad-ink:#f19a8f;--bad-line:#7a3a32;color-scheme:dark}
@media (prefers-color-scheme: dark){:root:not([data-theme="light"]){--bg:#111418;--surface:#181c21;--ink:#e8eaed;--muted:#9aa3ad;--line:#2a3038;--accent:#7fb2ea;--accent-ink:#0d1520;--accent-soft:#1a2633;--code-bg:#1b2027;--ok-bg:#173323;--ok-ink:#7fd39b;--ok-line:#2f6b45;--bad-bg:#3a1d1a;--bad-ink:#f19a8f;--bad-line:#7a3a32;color-scheme:dark}}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--ink);font:17px/1.7 Inter,system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;-webkit-font-smoothing:antialiased}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
.wrap{max-width:720px;margin:0 auto;padding:0 20px}
h1,h2,h3{font-family:Newsreader,Georgia,serif;font-weight:600;line-height:1.2;margin:0}

.top{display:flex;justify-content:space-between;align-items:center;gap:12px;padding-top:20px;padding-bottom:8px;font-size:.92rem;color:var(--muted)}
.top a{color:var(--muted)}
.top a:hover{color:var(--accent)}

header.wrap{padding-top:40px;padding-bottom:24px;border-bottom:1px solid var(--line)}
.tag{display:inline-block;font-size:.74rem;font-weight:600;letter-spacing:.04em;text-transform:uppercase;padding:2px 9px;border-radius:999px;background:var(--accent-soft);color:var(--accent);margin-bottom:14px}
header h1{font-size:clamp(1.9rem,5vw,2.6rem);letter-spacing:-.01em}
.dek{font-size:1.15rem;color:var(--muted);margin:12px 0 0}
.meta{font-size:.88rem;color:var(--muted);margin-top:14px}

article.wrap{padding-top:12px;padding-bottom:48px}
article h2{font-size:1.45rem;margin:36px 0 10px}
article p,article ul,article ol{margin:0 0 16px}
article li{margin:4px 0}
article code{font:.88em ui-monospace,SFMono-Regular,Menlo,monospace;background:var(--code-bg);padding:1px 6px;border-radius:5px}
article blockquote{margin:0 0 16px;padding:4px 0 4px 18px;border-left:3px solid var(--accent);color:var(--muted)}

footer.wrap{padding-top:28px;padding-bottom:56px;border-top:1px solid var(--line);color:var(--muted);font-size:.88rem;display:flex;justify-content:space-between;flex-wrap:wrap;gap:8px}

/* Buttons */
.btn{display:inline-flex;align-items:center;gap:8px;margin-top:18px;padding:8px 16px;border-radius:999px;background:var(--accent);color:var(--accent-ink);font-size:.92rem;font-weight:500}
.btn:hover{text-decoration:none;opacity:.9}
.btn svg{width:16px;height:16px;fill:currentColor}

/* Figures */
.fig{margin:22px 0 26px;padding:18px;background:var(--surface);border:1px solid var(--line);border-radius:14px}
.fig figcaption{margin-top:14px;font-size:.88rem;line-height:1.55;color:var(--muted)}

/* Figure: candidate intersection */
.fig1{display:flex;flex-wrap:wrap;gap:22px;align-items:center}
.sgrid{width:100%;max-width:250px;flex:0 0 auto}
.sgrid .cell{fill:var(--surface);stroke:var(--line);stroke-width:1}
.sgrid .hl-row,.sgrid .hl-col,.sgrid .hl-box{fill:color-mix(in srgb,var(--accent) 16%,var(--surface))}
.sgrid .hl-box.hl-row,.sgrid .hl-box.hl-col{fill:color-mix(in srgb,var(--accent) 26%,var(--surface))}
.sgrid .target{fill:var(--accent);stroke:var(--accent)}
.sgrid .thick{stroke:var(--ink);stroke-width:2;opacity:.7}
.sgrid text{font:600 15px Inter,system-ui,sans-serif;text-anchor:middle;fill:var(--ink)}
.sgrid .q{fill:var(--accent-ink);font-size:17px}
.sets{flex:1 1 220px;display:flex;flex-direction:column;gap:12px}
.set .lbl{display:block;font-size:.78rem;text-transform:uppercase;letter-spacing:.06em;color:var(--muted);margin-bottom:5px}
.chips{display:flex;gap:6px;flex-wrap:wrap}
.chip{display:inline-grid;place-items:center;width:30px;height:30px;border-radius:8px;border:1px solid var(--line);font-weight:600;font-size:.95rem;color:var(--muted);background:var(--bg)}
.chip.keep{background:var(--accent);border-color:var(--accent);color:var(--accent-ink)}
.result{padding-top:12px;border-top:1px dashed var(--line);font-size:.98rem}
.result .chip{width:26px;height:26px;margin:0 2px;vertical-align:middle}

/* Figure: flow */
.flow{list-style:none;margin:0;padding:0;counter-reset:none}
.flow .node{display:flex;gap:14px;align-items:flex-start;position:relative;padding:12px 14px;border:1px solid var(--line);border-radius:12px;background:var(--bg);margin:0}
.flow .node + .node{margin-top:22px}
.flow .node + .node::before{content:"";position:absolute;left:28px;top:-23px;height:22px;border-left:2px solid var(--line)}
.flow .node + .node::after{content:"";position:absolute;left:24px;top:-7px;border:5px solid transparent;border-top-color:var(--line)}
.flow .n{flex:0 0 auto;display:grid;place-items:center;width:28px;height:28px;border-radius:50%;background:var(--accent-soft);color:var(--accent);font-weight:600;font-size:.88rem}
.flow .node > div{font-size:.95rem;line-height:1.55}
.flow .stuck{border-color:var(--accent)}
.branch{display:block;width:max-content;max-width:100%;margin-top:7px;padding:2px 10px;border-radius:999px;font-size:.82rem;font-weight:600}
.branch.ok{background:var(--ok-bg);color:var(--ok-ink)}
.branch.bad{background:var(--bad-bg);color:var(--bad-ink)}
.branch.loop{background:var(--accent-soft);color:var(--accent)}

/* Figure: search tree */
.tree{width:100%;max-width:520px;height:auto;display:block;margin:0 auto}
.tree .edges path{fill:none;stroke:var(--muted);stroke-width:1.6}
.tree .ahead{fill:var(--muted)}
.tree .lbls text{font:500 13px Inter,system-ui,sans-serif;fill:var(--muted)}
.tree .tn{fill:var(--bg);stroke:var(--line);stroke-width:1.5}
.tree .tn.stuck{stroke:var(--accent)}
.tree .tn.bad{fill:var(--bad-bg);stroke:var(--bad-line)}
.tree .tn.ok{fill:var(--ok-bg);stroke:var(--ok-line)}
.tree .nodes text{font:600 14px Inter,system-ui,sans-serif;text-anchor:middle;fill:var(--ink)}

/* Tables */
.table-wrap{overflow-x:auto;margin:0 0 16px;border:1px solid var(--line);border-radius:12px}
table{width:100%;border-collapse:collapse;font-size:.9rem;font-variant-numeric:tabular-nums}
th,td{padding:9px 12px;text-align:left;white-space:nowrap;border-bottom:1px solid var(--line)}
th{font-weight:600;font-size:.8rem;text-transform:uppercase;letter-spacing:.04em;color:var(--muted);background:var(--surface)}
tbody tr:last-child td{border-bottom:none}
td.ok{color:var(--ok-ink);font-weight:600}
td.bad{color:var(--bad-ink);font-weight:600}

/* Photos and plan sheets */
.btn-row{display:flex;flex-wrap:wrap;gap:10px;margin-top:18px}
.btn-row .btn{margin-top:0}
.btn.ghost{background:var(--surface);color:var(--ink);border:1px solid var(--line)}
.btn.ghost:hover{border-color:var(--accent);color:var(--accent);opacity:1}
.photo{margin:24px 0 28px;text-align:center}
.photo img{display:block;width:auto;max-width:100%;height:auto;margin:0 auto;border-radius:14px;border:1px solid var(--line)}
.photo video{display:block;width:100%;max-width:720px;height:auto;margin:0 auto;border-radius:14px;border:1px solid var(--line);background:#fff}
.photo figcaption{margin-top:10px;font-size:.88rem;color:var(--muted)}
.fig.sheet{padding:12px}
.fig.sheet img{display:block;width:100%;height:auto;border-radius:8px;background:#fff}
.fine{font-size:.86rem;color:var(--muted);margin-top:18px}

/* Bar chart */
.bars{display:flex;flex-direction:column;gap:12px}
.bar-row{display:grid;grid-template-columns:minmax(150px,38%) 1fr;gap:14px;align-items:center}
.bar-label{font-size:.9rem;font-weight:500;line-height:1.3}
.bar-label small{display:block;font-weight:400;font-size:.8rem;color:var(--muted)}
.bar-track{display:flex;align-items:center;gap:8px}
.bar{display:block;height:18px;border-radius:5px;background:color-mix(in srgb,var(--accent) 35%,var(--surface))}
.bar-row.final .bar{background:var(--accent)}
.bar-row.final .bar-label{color:var(--accent)}
.bar-val{font-size:.85rem;font-variant-numeric:tabular-nums;color:var(--muted);white-space:nowrap}
@media (max-width:520px){.bar-row{grid-template-columns:1fr;gap:4px}}

/* Build photo gallery */
.gallery{display:grid;grid-template-columns:repeat(2,1fr);gap:12px;margin:20px 0 24px}
.gallery figure{margin:0}
.gallery a{display:block;border-radius:12px;overflow:hidden;border:1px solid var(--line)}
.gallery img{display:block;width:100%;height:auto;aspect-ratio:4/3;object-fit:cover;transition:transform .2s}
.gallery a:hover img{transform:scale(1.03)}
.gallery figcaption{margin-top:6px;font-size:.85rem;color:var(--muted);line-height:1.4}
@media (max-width:520px){.gallery{grid-template-columns:1fr}}
.gallery figure:last-child:nth-child(odd){grid-column:1/-1}
.gallery figure:last-child:nth-child(odd) img{aspect-ratio:16/9}