/* ============================================================
   AUDIO DSP HUB — strict technical documentation stylesheet
   CSS-only. No active layer of any kind.
   ============================================================ */
:root{
  --bg:#F8FAFC; --navy:#0F172A; --slate:#1E293B;
  --accent:#0284C7; --accent-2:#0369A1; --ink:#0B1220;
  --rule:#CBD5E1; --rule-2:#E2E8F0; --card:#FFFFFF;
  --muted:#475569; --tint:#E0F2FE; --tint-2:#F1F5F9;
  --f-head:Inter,"Helvetica Neue",Arial,sans-serif;
  --f-mono:"IBM Plex Mono","DejaVu Sans Mono",Consolas,monospace;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{
  margin:0;background:var(--bg);color:var(--slate);
  font:16px/1.65 var(--f-head);
}
img{max-width:100%;height:auto;display:block;border-radius:2px}
a{color:var(--accent-2)}
a:hover{color:var(--ink)}
h1,h2,h3,h4{color:var(--navy);line-height:1.2;margin:0 0 .5em}
h1{font-size:2rem;letter-spacing:-.01em}
h2{font-size:1.35rem;margin-top:1.8em}
h3{font-size:1.08rem;margin-top:1.4em}
p{margin:0 0 1em}
code,kbd,samp{font-family:var(--f-mono);font-size:.9em;background:var(--tint-2);padding:.05em .35em;border-radius:3px}
.skip{position:absolute;left:-9999px}
.skip:focus{left:8px;top:8px;z-index:99;background:var(--navy);color:#fff;padding:8px 12px}
.wrap{max-width:1080px;margin:0 auto;padding:0 20px}
/* ---------- Console desk header (fader bank navigation) ---------- */
.desk{position:sticky;top:0;z-index:40;background:var(--navy);
  border-bottom:3px solid var(--accent);box-shadow:0 6px 18px rgba(15,23,42,.22)}
.desk-in{max-width:1180px;margin:0 auto;padding:10px 20px;
  display:flex;align-items:stretch;gap:22px}
.brand{display:flex;align-items:center;gap:11px;text-decoration:none;flex:0 0 auto}
.monogram{display:inline-flex;align-items:flex-end;gap:3px;height:26px}
.monogram i{display:block;width:5px;background:var(--accent)}
.monogram i:nth-child(1){height:11px}
.monogram i:nth-child(2){height:20px;background:#38BDF8}
.monogram i:nth-child(3){height:26px}
.wordmark{color:#F8FAFC;font-weight:700;font-size:.92rem;letter-spacing:.2em;font-family:var(--f-mono)}
.fader-bank{display:flex;gap:6px;align-items:stretch;margin-left:auto}
.chan{position:relative;flex:0 0 auto}
.chan>summary{list-style:none;cursor:pointer;display:flex;flex-direction:column;
  align-items:center;gap:3px;padding:6px 12px 8px;border:1px solid #334155;border-radius:4px;
  background:#152238;min-width:92px}
.chan>summary::-webkit-details-marker{display:none}
.chan>summary:hover{border-color:#64748B}
.code{font-family:var(--f-mono);font-size:.62rem;letter-spacing:.12em;color:#94A3B8}
.cname{font-size:.7rem;font-weight:600;color:#E2E8F0;text-transform:uppercase;letter-spacing:.08em}
.lane{position:relative;width:12px;height:30px;display:block}
.trk{position:absolute;left:5px;top:0;bottom:0;width:2px;background:#475569}
.knob{position:absolute;left:0;width:12px;height:7px;background:#94A3B8;border-radius:2px;
  top:18px;transition:top .15s}
.chan.raised>summary{background:var(--slate);border-color:var(--accent)}
.chan.raised .knob{top:3px;background:var(--accent)}
.chan.raised .trk{background:var(--accent-2)}
.chan.raised .cname{color:#FFFFFF}
.chan.raised .code{color:#7DD3FC}
.clist{position:absolute;right:0;top:calc(100% + 6px);min-width:236px;margin:0;padding:8px;
  list-style:none;background:var(--card);border:1px solid var(--rule);border-radius:6px;
  box-shadow:0 14px 30px rgba(15,23,42,.2);z-index:50}
.clist li{margin:0}
.clist a{display:block;padding:7px 10px;text-decoration:none;color:var(--slate);
  font-size:.86rem;border-radius:4px;border-left:3px solid transparent}
.clist a:hover{background:var(--tint);color:var(--ink)}
.clist a[aria-current="page"]{background:var(--tint);border-left-color:var(--accent);
  color:var(--ink);font-weight:600}
/* ---------- Content primitives ---------- */
main{display:block}
.sec{padding:34px 0 8px}
.lead{font-size:1.08rem;color:var(--muted)}
.hero{background:linear-gradient(180deg,#0F172A 0%,#1E293B 100%);color:#E2E8F0;
  padding:46px 0 40px;border-bottom:1px solid #334155}
.hero h1{color:#FFFFFF;max-width:20ch}
.hero p{color:#CBD5E1;max-width:62ch}
.hero .btn{display:inline-block;margin-top:14px;padding:11px 20px;border:1px solid var(--accent);
  border-radius:4px;color:#FFFFFF;background:var(--accent);text-decoration:none;
  font-weight:600;letter-spacing:.03em}
.hero .btn:hover{background:var(--accent-2);border-color:var(--accent-2);color:#fff}
.grid{display:grid;gap:16px}
.g2{grid-template-columns:repeat(2,1fr)}
.g3{grid-template-columns:repeat(3,1fr)}
.card{background:var(--card);border:1px solid var(--rule);border-radius:6px;padding:18px 18px 6px}
.card h3{margin-top:0}
.card p:last-child{margin-bottom:.7em}
.links{margin:0;padding-left:1.1em}
.links li{margin:.25em 0}
figure{margin:22px 0;background:var(--card);border:1px solid var(--rule);border-radius:6px;
  padding:12px;overflow:hidden}
figcaption{font-family:var(--f-mono);font-size:.72rem;color:var(--muted);
  letter-spacing:.04em;padding:8px 2px 2px}
.tbl{width:100%;border-collapse:collapse;font-family:var(--f-mono);font-size:.78rem;
  background:var(--card);margin:14px 0}
.tbl caption{text-align:left;font-family:var(--f-head);font-size:.78rem;color:var(--muted);
  padding:6px 2px 8px;letter-spacing:.02em}
.tbl th,.tbl td{border:1px solid var(--rule);padding:7px 9px;text-align:left;vertical-align:top}
.tbl thead th{background:var(--navy);color:#E2E8F0;font-weight:600}
.tbl tbody tr:nth-child(even){background:var(--tint-2)}
.note{border-left:4px solid var(--accent);background:var(--tint);padding:12px 16px;
  border-radius:0 5px 5px 0;margin:16px 0;font-size:.94rem}
.mono{font-family:var(--f-mono)}
/* ---------- CSS-only tabs (radio + label) ---------- */
.tabs{background:var(--card);border:1px solid var(--rule);border-radius:6px;padding:0 0 4px;margin:18px 0}
.tabs input{position:absolute;left:-9999px}
.tabbar{display:flex;flex-wrap:wrap;gap:0;border-bottom:1px solid var(--rule)}
.tabbar label{padding:11px 18px;cursor:pointer;font-size:.82rem;font-weight:600;
  letter-spacing:.05em;text-transform:uppercase;color:var(--muted);border-bottom:3px solid transparent}
.tabbar label:hover{background:var(--tint-2);color:var(--ink)}
.pane{display:none;padding:16px 18px 20px}
#t1:checked~.tabbar label[for="t1"],
#t2:checked~.tabbar label[for="t2"],
#t3:checked~.tabbar label[for="t3"]{color:var(--navy);border-bottom-color:var(--accent);background:var(--tint)}
#t1:checked~#p1,#t2:checked~#p2,#t3:checked~#p3{display:block}
/* ---------- Signal-chain figure ---------- */
.chain{display:flex;flex-wrap:wrap;align-items:center;gap:8px;padding:14px 10px}
.node{border:1px solid var(--rule);background:var(--tint-2);border-radius:5px;
  padding:9px 12px;font-family:var(--f-mono);font-size:.74rem;color:var(--slate)}
.node b{display:block;color:var(--navy);font-size:.68rem;letter-spacing:.08em}
.arrow{color:var(--accent);font-weight:700}
/* ---------- Meter figures ---------- */
.meter{display:grid;gap:6px;padding:12px 8px}
.rowm{display:grid;grid-template-columns:84px 1fr 62px;align-items:center;gap:10px;
  font-family:var(--f-mono);font-size:.72rem}
.bar{height:12px;background:var(--tint-2);border:1px solid var(--rule-2);border-radius:3px;overflow:hidden}
.bar span{display:block;height:100%;background:var(--accent)}
.bar span.warn{background:#D97706}
.bar span.hot{background:#DC2626}
/* ---------- Forms ---------- */
.form{background:var(--card);border:1px solid var(--rule);border-radius:6px;padding:20px;
  max-width:640px}
.form .field{margin-bottom:14px}
.form label{display:block;font-size:.8rem;font-weight:600;letter-spacing:.04em;
  text-transform:uppercase;color:var(--navy);margin-bottom:5px}
.form input,.form textarea,.form select{width:100%;padding:9px 10px;border:1px solid var(--rule);
  border-radius:4px;font:15px var(--f-head);color:var(--slate);background:#fff}
.form textarea{min-height:120px;resize:vertical}
.form .send{margin-top:8px;padding:11px 22px;background:var(--accent);color:#fff;border:1px solid var(--accent);
  border-radius:4px;font:600 15px var(--f-head);cursor:pointer;letter-spacing:.03em}
.form .send:hover{background:var(--accent-2)}
/* ---------- Footer ---------- */
.foot{background:var(--navy);color:#CBD5E1;margin-top:40px;padding:34px 0 0;
  border-top:3px solid var(--accent);font-size:.88rem}
.foot h4{color:#FFFFFF;font-size:.78rem;letter-spacing:.14em;text-transform:uppercase;
  font-family:var(--f-mono);margin:0 0 .8em}
.foot a{color:#7DD3FC;text-decoration:none}
.foot a:hover{color:#fff;text-decoration:underline}
.fgrid{display:grid;grid-template-columns:1.3fr 1fr 1fr 1fr;gap:22px}
.fgrid ul{list-style:none;margin:0;padding:0}
.fgrid li{margin:.3em 0}
.addr{font-family:var(--f-mono);font-size:.78rem;line-height:1.7;color:#94A3B8}
.fbottom{border-top:1px solid #334155;margin-top:26px;padding:14px 0 18px;
  display:flex;flex-wrap:wrap;gap:10px;justify-content:space-between;
  font-size:.74rem;color:#94A3B8;font-family:var(--f-mono)}
/* ---------- Static cookie band ---------- */
.cookie{background:var(--slate);color:#E2E8F0;border-top:1px solid #334155;padding:12px 0}
.cookie .wrap{display:flex;flex-wrap:wrap;gap:12px;align-items:center;justify-content:space-between}
.cookie p{margin:0;font-size:.8rem}
.cookie a{color:#7DD3FC}
.legal{padding:26px 0 10px;max-width:820px}
.legal h2{margin-top:1.5em}
/* ---------- Utilities ---------- */
.kicker{font-family:var(--f-mono);font-size:.72rem;letter-spacing:.18em;text-transform:uppercase;color:var(--accent)}
.center{text-align:center}
ul.tight li{margin:.3em 0}
hr{border:0;border-top:1px solid var(--rule);margin:26px 0}
/* ---------- Responsive: console becomes a scroll row of chips ---------- */
@media (max-width:860px){
  .fgrid{grid-template-columns:1fr 1fr}
  .g3{grid-template-columns:1fr 1fr}
}
@media (max-width:760px){
  .desk-in{flex-direction:column;gap:10px;padding:10px 14px}
  .fader-bank{width:100%;overflow-x:auto;margin-left:0;padding-bottom:6px}
  .chan>summary{min-width:84px;padding:5px 9px 7px}
  .chan .lane{height:22px}
  .knob{top:13px}
  .chan.raised .knob{top:2px}
  .clist{position:static;min-width:0;width:100%;box-shadow:none;margin-top:8px}
  .chan[open]{flex:1 1 100%}
  .g2,.g3{grid-template-columns:1fr}
  .fgrid{grid-template-columns:1fr}
  .hero h1{font-size:1.5rem}
  h1{font-size:1.5rem}
  .rowm{grid-template-columns:70px 1fr 54px}
}
@media print{.desk,.cookie{display:none}}
/* ---------- Q&A blocks ---------- */
.qa{background:var(--card);border:1px solid var(--rule);border-radius:6px;margin:10px 0;padding:0 16px}
.qa summary{cursor:pointer;padding:13px 0;font-weight:600;color:var(--navy);font-size:.98rem}
.qa summary:hover{color:var(--accent-2)}
.qa p{margin:0 0 .9em}
.qa[open]{border-color:var(--accent);box-shadow:0 4px 14px rgba(2,132,199,.09)}