/* DP Science Cafe — one stylesheet, no external fonts, no framework. */
:root{
  --bg:#faf8f3; --fg:#1d1d1b; --muted:#5f625c; --line:#dcd7cb; --accent:#1f3a34; --accent-fg:#fff;
  --hl:#7a4a12; --hl-bg:#fbf1e3; --ok:#1d6b3a; --bad:#9b2c2c; --panel:#fff; --rail:#f2efe7;
  --maxw:44rem; --railw:17rem; --fs:1.125rem;
}
@media (prefers-color-scheme:dark){:root{--bg:#141514;--fg:#ebe8e0;--muted:#a6a89f;--line:#33352f;--accent:#8fc1b3;--accent-fg:#101;--hl:#e0b170;--hl-bg:#241c10;--ok:#7fd59a;--bad:#f08a8a;--panel:#1b1d1a;--rail:#1a1c19}}
*{box-sizing:border-box}
html{font-size:var(--fs);-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--fg);font:1rem/1.55 system-ui,-apple-system,"Segoe UI",Roboto,Helvetica,Arial,sans-serif}
a{color:inherit;text-underline-offset:.15em}
a:hover{color:var(--accent)}
.skip{position:absolute;left:-999px;top:0;background:var(--accent);color:var(--accent-fg);padding:.5rem}
.skip:focus{left:.5rem}
.top{display:flex;align-items:center;gap:1rem;padding:.6rem 1rem;border-bottom:1px solid var(--line)}
.brand{font-weight:700;text-decoration:none;letter-spacing:.01em}
.rail-toggle{border:1px solid var(--line);background:var(--panel);color:inherit;padding:.35rem .7rem;border-radius:.4rem;font:inherit}
.frame{display:grid;grid-template-columns:1fr;max-width:calc(var(--maxw) + var(--railw) + 4rem);margin:0 auto}
main{padding:1.25rem 1rem 3rem;max-width:var(--maxw);width:100%}
.foot{border-top:1px solid var(--line);padding:1.25rem 1rem 2rem;color:var(--muted);font-size:.9rem;text-align:center}
.foot p{margin:.25rem 0}

/* Rail */
.rail{background:var(--rail);border-bottom:1px solid var(--line);padding:.9rem 1rem;font-size:.92rem}
.rail ol,.rail ul{list-style:none;margin:0;padding:0}
.rail .path li{display:inline}
.rail .path li+li::before{content:" › ";color:var(--muted)}
.rail .path a{display:inline-block;padding:.15rem 0;min-height:1.5rem}
.rail .path a[aria-current]{font-weight:700;text-decoration:none}
.rail-h{margin:1rem 0 .3rem;color:var(--muted);font-size:.8rem;text-transform:uppercase;letter-spacing:.06em}
.rail .topics li,.rail .themes li{padding:.15rem 0}
.rail .topics a,.rail .themes a{text-decoration:none;display:block;padding:.15rem .4rem;border-radius:.3rem}
.rail .topics a[aria-current]{background:var(--accent);color:var(--accent-fg)}
.rail .topics a[aria-current] .code{color:inherit}
.code{font-variant-numeric:tabular-nums;color:var(--muted);font-weight:600;margin-right:.2em}
.modes{display:flex;gap:.4rem;margin:.9rem 0 0}
.modes a,.modes-inline a{flex:1;text-align:center;text-decoration:none;border:1px solid var(--line);border-radius:.4rem;padding:.4rem .5rem;background:var(--panel)}
.modes a[aria-current],.modes-inline a[aria-current]{background:var(--accent);color:var(--accent-fg);border-color:var(--accent)}
.hl-toggle{display:inline-flex;align-items:center;gap:.4rem;margin-top:.9rem;color:var(--muted)}
@media (min-width:60rem){
  .frame{grid-template-columns:var(--railw) 1fr;gap:2rem;padding:0 1rem}
  .rail{position:sticky;top:0;align-self:start;max-height:100vh;overflow:auto;border-bottom:0;border-right:1px solid var(--line);padding:1.25rem 1rem 1.25rem 0;background:transparent}
  .rail-toggle{display:none!important}
  main{padding-left:0}
}
@media (max-width:59.99rem){
  .rail-toggle[hidden]{display:inline-block}
  body.js .rail{display:none}
  body.js .rail.open{display:block}
}

/* Heads */
h1{font-size:1.9rem;line-height:1.2;margin:.2rem 0 .6rem;letter-spacing:-.01em}
h2{font-size:1.35rem;margin:2rem 0 .6rem}
h3{font-size:1.1rem;margin:1.4rem 0 .4rem}
.kicker{color:var(--muted);margin:0;font-size:.9rem}
.lede{font-size:1.1rem;color:var(--muted);margin:.2rem 0 1rem}
.summary{font-size:1.1rem;line-height:1.5;margin:.4rem 0 .8rem;max-width:38rem}
.summary.muted{color:var(--muted)}
.muted{color:var(--muted)}
.small{font-size:.85rem}
.status{color:var(--muted);font-size:.85rem;margin:.2rem 0 1rem}
.foot-status{border-top:1px solid var(--line);margin-top:2rem;padding-top:.8rem}
.linklike{font:inherit;color:inherit;background:none;border:0;padding:0;text-decoration:underline;cursor:pointer}
.specbox{border:1px solid var(--line);border-radius:.6rem;background:var(--panel);padding:.6rem .9rem;margin:0 0 1.2rem}
.specbox summary{cursor:pointer;font-weight:600}
.spec-list{margin:.5rem 0 .3rem;padding-left:0;list-style:none;columns:2;column-gap:1.5rem;font-size:.92rem}
.spec-list li{break-inside:avoid;padding:.15rem 0}
.spec-list a{text-decoration:none}
.spec-list a:hover{text-decoration:underline}
@media (max-width:40rem){.spec-list{columns:1}.summary{font-size:1rem}}
.points{margin:.3rem 0 .6rem;padding-left:1.2rem}
.points li{margin:.25rem 0;line-height:1.45}
.exam-frame{border:1px solid var(--line);border-radius:.6rem;padding:.7rem 1rem;background:var(--panel);margin:.8rem 0}
.exam-frame h4{margin:0 0 .4rem;font-size:1rem}
.meta{color:var(--muted);font-size:.9rem}
.badge{display:inline-block;font-size:.7rem;font-weight:700;letter-spacing:.05em;color:var(--hl);background:var(--hl-bg);border-radius:.3rem;padding:.05rem .4rem;vertical-align:middle}
.modes-inline{display:flex;gap:.6rem;margin:1rem 0 1.5rem;flex-wrap:wrap}
.modes-inline a{display:flex;flex-direction:column;gap:.1rem;padding:.6rem .8rem;min-width:9rem}
.modes-inline a span{font-size:.85rem;color:var(--muted)}
.modes-inline a[aria-current] span{color:inherit;opacity:.85}

/* Home / subject / theme */
.subjects{display:grid;gap:1rem;grid-template-columns:repeat(auto-fit,minmax(15rem,1fr))}
.card{display:block;border:1px solid var(--line);border-radius:.6rem;padding:1rem 1.1rem;background:var(--panel);text-decoration:none}
.card h2{margin:0 0 .3rem;font-size:1.2rem}
.card.soon{color:var(--muted);background:transparent}
.mini-map{list-style:none;padding:0;margin:.6rem 0 0;font-size:.9rem;color:var(--muted)}
.map{width:100%;border-collapse:collapse;font-size:.92rem}
.map th,.map td{vertical-align:top;text-align:left;padding:.6rem .5rem;border-top:1px solid var(--line)}
.map thead th{border-top:0;color:var(--muted);font-weight:600;font-size:.8rem;text-transform:uppercase;letter-spacing:.05em}
.map ul{list-style:none;margin:0;padding:0}
.map li{margin:.15rem 0}
.map a,.topic-list a{text-decoration:none}
.map a:hover,.topic-list a:hover{text-decoration:underline}
.topic-list{list-style:none;padding:0;margin:0}
.topic-list li{padding:.5rem 0;border-top:1px solid var(--line)}
@media (max-width:40rem){.map thead{display:none}.map tr,.map td,.map th{display:block;padding:.3rem .2rem}.map td::before{content:attr(data-l);color:var(--muted)}}

/* Panels */
.panel{margin-top:1.5rem}
.panel-h{border-top:2px solid var(--line);padding-top:1rem}
.panel-h small{color:var(--muted);font-weight:400;font-size:.85rem;margin-left:.4rem}
body.js .panel[hidden]{display:none}
.notice{border-left:3px solid var(--line);padding:.4rem .8rem;color:var(--muted);font-size:.92rem}
.stmt{padding:.2rem 0 .6rem;border-top:1px solid var(--line)}
.stmt h3{margin-top:.9rem}
.stmt.hl{background:var(--hl-bg);border-top-color:transparent;padding:.2rem .8rem .6rem;border-radius:.4rem;margin-top:.6rem}
.scope{font-size:.9rem;color:var(--muted);border-left:3px solid var(--hl);padding:.2rem .7rem}
.terms{margin:.4rem 0}
.terms dt{font-weight:600;margin-top:.5rem}
.terms dd{margin:0 0 .2rem}
.callout{border-left:3px solid var(--accent);padding:.3rem .8rem;margin:.6rem 0;background:var(--panel)}
body.sl-only .hl{display:none}

/* Questions */
.q{border:1px solid var(--line);border-radius:.6rem;padding:.9rem 1rem;margin:1rem 0;background:var(--panel)}
.q.hl{border-color:var(--hl)}
.stem{margin:0 0 .6rem;font-weight:600}
.stem .n{display:inline-block;min-width:1.6em;color:var(--muted);font-weight:600}
.opts{margin:0;padding-left:1.6rem}
.opts li{margin:.35rem 0}
.opt{font:inherit;text-align:left;width:100%;background:transparent;color:inherit;border:1px solid var(--line);border-radius:.4rem;padding:.45rem .7rem;cursor:pointer}
body.js .opt:hover{border-color:var(--accent)}
.opt.chosen.right{border-color:var(--ok);background:color-mix(in srgb,var(--ok) 10%,transparent)}
.opt.chosen.wrong{border-color:var(--bad);background:color-mix(in srgb,var(--bad) 10%,transparent)}
.opt.reveal{border-color:var(--ok)}
.q.answered .opt{cursor:default}
.answer{margin-top:.7rem}
.answer summary{cursor:pointer;color:var(--muted)}
.answer ol{padding-left:1.6rem}
.answer li{margin:.3rem 0}
.answer li.correct{color:var(--ok)}
.answer li.correct strong{color:var(--ok)}
body.js .q:not(.answered) .answer{display:none}
.actions{margin:1.2rem 0}
.primary{font:inherit;background:var(--accent);color:var(--accent-fg);border:0;border-radius:.4rem;padding:.6rem 1rem;cursor:pointer}
.result{border:1px solid var(--line);border-radius:.6rem;padding:1rem;background:var(--panel);margin:1.2rem 0}
.stmt-map{list-style:none;padding:0;margin:0}
.stmt-map li{display:flex;justify-content:space-between;gap:1rem;padding:.35rem 0;border-top:1px solid var(--line)}
.stmt-map a{text-decoration:none}
.mark{font-size:.85rem;font-weight:600;white-space:nowrap}
.mark.own{color:var(--ok)}.mark.notyet{color:var(--bad)}.mark.unasked{color:var(--muted)}
.sendoff{border-top:2px solid var(--line);margin-top:2rem;padding-top:.5rem}
.nextprev{display:flex;justify-content:space-between;gap:1rem;flex-wrap:wrap}
.prose p,.prose li{max-width:40rem}

/* Print: one clean sheet per topic. No PDFs are generated or served; the browser does it. */
@media print{
  :root{--bg:#fff;--fg:#000;--muted:#444;--line:#999;--panel:#fff;--hl-bg:#f3f3f3}
  .top,.rail,.foot,.modes-inline,.actions,.rail-toggle,#print-topic,.result,.skip{display:none!important}
  .frame{display:block;max-width:none;padding:0}
  main{max-width:none;padding:0}
  body{font-size:10.5pt;line-height:1.4}
  h1{font-size:18pt;margin:0 0 .3rem}
  h2.panel-h{font-size:13pt;border-top:1px solid #000;page-break-before:auto}
  body.js .panel[hidden]{display:block!important}
  .panel{margin-top:.8rem}
  .specbox{page-break-inside:avoid}
  .q{page-break-inside:avoid;border:1px solid #bbb;padding:.4rem .6rem;margin:.4rem 0}
  .opt{border:0;padding:0 0 0 .2rem}
  body.js .q:not(.answered) .answer{display:block}
  .answer summary{display:none}
  .answer{font-size:9pt}
  .answer li.correct{font-weight:700}
  .stmt.hl{background:#f3f3f3}
  a{text-decoration:none;color:inherit}
  .nextprev{display:none}
  main::after{content:"dpsciencecafe.com" attr(data-url);display:block;margin-top:1rem;font-size:9pt;color:#444}
}