/* style.css — shared look for every scheduler page */
:root{
  --bg:#f7f5f1;
  --panel:#ffffff;
  --ink:#1f2420;
  --muted:#6b7268;
  --line:#e2ddd3;
  --accent:#2f6f5e;
  --accent-ink:#ffffff;
  --accent-soft:#e4efe9;
  --warn:#b4552f;
  --font-display:'Fraunces',Georgia,'Times New Roman',serif;
  --font-body:'Inter',system-ui,-apple-system,sans-serif;
  --font-mono:'JetBrains Mono',ui-monospace,Menlo,Consolas,monospace;
}
@media (prefers-color-scheme: dark){
  :root{
    --bg:#15181a; --panel:#1d2124; --ink:#eef0ec; --muted:#9aa29c;
    --line:#2d3235; --accent:#5fae97; --accent-ink:#0f1512; --accent-soft:#1f2d29; --warn:#d98461;
  }
}
*{box-sizing:border-box}
html,body{margin:0}
body{
  background:var(--bg); color:var(--ink); font-family:var(--font-body);
  padding-inline:16px; padding-block:24px 48px;
}
.wrap{max-width:1180px;margin:0 auto}

a{color:var(--accent)}
.topnav{
  display:flex; align-items:center; gap:14px; flex-wrap:wrap;
  margin-bottom:22px; font-size:13px;
}
.topnav a{
  text-decoration:none; color:var(--muted); font-weight:600;
  padding:6px 10px; border-radius:7px; border:1px solid transparent;
}
.topnav a.current{ color:var(--ink); background:var(--accent-soft); border-color:var(--accent); }
.topnav a:hover{ color:var(--ink); }
.topnav .brand{
  font-family:var(--font-display); font-weight:600; font-size:15px; color:var(--ink); margin-right:6px;
}

.eyebrow{
  font-family:var(--font-mono); font-size:11px; letter-spacing:.14em; text-transform:uppercase;
  color:var(--accent); margin:0 0 8px;
}
h1{
  font-family:var(--font-display); font-weight:600; font-size:clamp(26px,4vw,38px);
  margin:0 0 8px; text-wrap:balance;
}
.sub{color:var(--muted); max-width:66ch; line-height:1.55; margin:0 0 4px; font-size:15px}

.layout{display:grid; grid-template-columns:320px 1fr; gap:20px; align-items:start; margin-top:22px}
@media (max-width:760px){ .layout{grid-template-columns:1fr} }

.panel{ background:var(--panel); border:1px solid var(--line); border-radius:14px; padding:18px; }
.panel + .panel{margin-top:16px}
.panel h2{ font-family:var(--font-display); font-size:17px; margin:0 0 4px; font-weight:600; }
.panel .hint{color:var(--muted); font-size:12.5px; margin:0 0 14px; line-height:1.45}

label.field{display:block;margin-bottom:12px}
label.field span{
  display:block;font-size:11.5px;color:var(--muted);
  text-transform:uppercase;letter-spacing:.06em;margin-bottom:5px;
}
select,input[type=number]{
  width:100%; font-family:var(--font-body); font-size:14px; padding:9px 10px;
  border-radius:8px; border:1px solid var(--line); background:var(--bg); color:var(--ink);
}
select:focus,input:focus,button:focus-visible{ outline:2px solid var(--accent); outline-offset:1px; }

table.proc{ width:100%; border-collapse:collapse; font-size:13.5px; margin-bottom:10px; table-layout:fixed; }
table.proc th{
  text-align:left;font-size:11px;text-transform:uppercase;letter-spacing:.05em;
  color:var(--muted);font-weight:600;padding:0 6px 6px;border-bottom:1px solid var(--line);
}
table.proc td{padding:5px 6px;border-bottom:1px solid var(--line)}
table.proc input{
  width:100%;padding:5px 6px;border-radius:6px;border:1px solid var(--line);
  background:var(--bg);color:var(--ink);font-family:var(--font-mono);font-size:13px;
}
table.proc .swatch{width:10px;height:10px;border-radius:3px;display:inline-block}
.row-del{ background:none;border:none;color:var(--muted);cursor:pointer;font-size:16px;line-height:1; padding:2px 6px;border-radius:5px; }
.row-del:hover{color:var(--warn);background:var(--accent-soft)}

.btn{
  font-family:var(--font-body);font-weight:600;font-size:13px;
  padding:8px 14px;border-radius:8px;border:1px solid var(--line);
  background:var(--bg);color:var(--ink);cursor:pointer;
}
.btn.primary{background:var(--accent);color:var(--accent-ink);border-color:var(--accent)}
.btn:disabled{opacity:.45;cursor:default}
.btn-row{display:flex;gap:8px;margin-top:8px;flex-wrap:wrap}

.result-head{display:flex;justify-content:space-between;align-items:baseline;gap:12px;flex-wrap:wrap}
.result-head h2{margin:0}
.algo-desc{color:var(--muted);font-size:13px;margin:4px 0 16px;line-height:1.5;max-width:70ch}

/* ---------- playback controls ---------- */
.playbar{
  display:flex; align-items:center; gap:10px; flex-wrap:wrap;
  background:var(--accent-soft); border-radius:10px; padding:10px 12px; margin-bottom:16px;
}
.playbar .btn{min-width:38px}
.playbar .speedwrap{display:flex;align-items:center;gap:7px;font-size:12px;color:var(--muted);margin-left:auto}
.playbar input[type=range]{width:110px}
.playbar .clock{
  font-family:var(--font-mono); font-weight:700; font-size:14px; color:var(--ink);
  background:var(--panel); border:1px solid var(--line); border-radius:7px; padding:4px 10px;
  min-width:52px; text-align:center;
}
.running-badge{
  font-family:var(--font-mono); font-size:12.5px; font-weight:700;
  padding:5px 11px; border-radius:999px; background:var(--panel); border:1px solid var(--line);
  color:var(--muted); transition:background .15s,color .15s,border-color .15s;
}
.running-badge.active{color:var(--accent-ink)}

/* ---------- gantt ---------- */
.gantt-scroll{overflow-x:auto;overflow-y:hidden;padding-bottom:18px}
.gantt{position:relative;min-width:fit-content}
.gantt-track{
  position:relative; display:flex; border-radius:8px; overflow:hidden;
  border:1px solid var(--line); background:var(--bg);
}
.gslice{
  position:relative; display:flex; align-items:center; justify-content:center;
  height:48px; font-family:var(--font-mono); font-size:12.5px; font-weight:600;
  color:#fff; overflow:hidden; flex:none;
}
.gslice .fill{
  position:absolute; inset:0; width:0%; display:flex; align-items:center; justify-content:center;
  transition:none;
}
.gslice.idle .fill{
  background:repeating-linear-gradient(135deg, var(--line), var(--line) 6px, transparent 6px, transparent 12px);
  background-color:var(--bg); color:var(--muted);
}
.gslice .ghost{ position:absolute; inset:0; background:var(--line); opacity:.35; }
.gslice + .gslice{border-left:1px solid rgba(0,0,0,.12)}

.playhead{
  position:absolute; top:-4px; bottom:-4px; width:2px; background:var(--warn);
  box-shadow:0 0 0 3px color-mix(in srgb, var(--warn) 25%, transparent);
  left:0; pointer-events:none; border-radius:2px;
}

.gticks{display:flex;margin-top:4px;font-family:var(--font-mono);font-size:11px;color:var(--muted);position:relative}
.gtick{position:relative;flex:none;text-align:left}
.gtick span{position:absolute;left:-1px;transform:translateX(-50%)}

.legend{display:flex;gap:10px;flex-wrap:wrap;margin:14px 0 2px;font-size:12.5px}
.legend-item{display:flex;align-items:center;gap:6px;color:var(--muted);transition:opacity .2s}
.legend .swatch{width:10px;height:10px;border-radius:3px;flex:none}

.metrics{
  display:grid; gap:1px; background:var(--line);
  border:1px solid var(--line); border-radius:10px; overflow:hidden; margin-top:18px;
}
.metrics table{width:100%;border-collapse:collapse;background:var(--panel)}
.metrics th,.metrics td{
  padding:8px 10px;font-size:13px;text-align:right;font-variant-numeric:tabular-nums;
  border-bottom:1px solid var(--line);
}
.metrics th{ text-align:left;color:var(--muted);font-weight:600;font-size:11.5px; text-transform:uppercase;letter-spacing:.04em; }
.metrics td:first-child,.metrics th:first-child{text-align:left}
.metrics tfoot td{font-weight:700;border-bottom:none;background:var(--accent-soft)}
.metrics tbody tr{ opacity:0; transform:translateY(4px); transition:opacity .35s, transform .35s; }
.metrics tbody tr.shown{opacity:1;transform:none}

.stat-strip{display:flex;gap:10px;flex-wrap:wrap;margin-top:16px}
.stat{ flex:1;min-width:140px;background:var(--accent-soft);border-radius:10px;padding:12px 14px; }
.stat .n{font-family:var(--font-display);font-size:24px;font-weight:600;line-height:1;font-variant-numeric:tabular-nums}
.stat .l{font-size:11.5px;color:var(--muted);text-transform:uppercase;letter-spacing:.05em;margin-top:4px}

.quantum-note{
  font-size:12.5px;color:var(--muted);background:var(--accent-soft);
  border-radius:8px;padding:8px 11px;margin-top:10px;line-height:1.5;
}
.quantum-note b{color:var(--ink)}

footer.credit{margin-top:34px;color:var(--muted);font-size:12px;text-align:center}

@media (prefers-reduced-motion: reduce){
  .metrics tbody tr{transition:none}
}

/* ============== Chapter 6 — trace-player additions ============== */

.mode-row{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:4px}
.mode-row .btn.active{background:var(--accent);color:var(--accent-ink);border-color:var(--accent)}

.frame-counter{
  font-family:var(--font-mono);font-size:12.5px;color:var(--muted);
  background:var(--panel);border:1px solid var(--line);border-radius:7px;
  padding:4px 10px;min-width:72px;text-align:center;
}

.actor-grid{display:grid;gap:12px;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));margin-bottom:16px}
.actor-lane{border:1px solid var(--line);border-radius:10px;overflow:hidden;background:var(--bg)}
.actor-head{
  display:flex;align-items:center;gap:7px;padding:8px 10px;font-weight:700;font-size:13px;
  background:var(--panel);border-bottom:1px solid var(--line);
}
.actor-dot{width:10px;height:10px;border-radius:3px;flex:none}
.actor-head .tag{
  margin-left:auto;font-family:var(--font-mono);font-size:10.5px;text-transform:uppercase;
  letter-spacing:.05em;color:var(--muted);padding:2px 7px;border-radius:999px;background:var(--bg);
  border:1px solid var(--line);
}
.actor-head .tag.live{color:var(--accent-ink);background:var(--accent);border-color:var(--accent)}
.actor-head .tag.spin{color:var(--warn);border-color:var(--warn);background:transparent}
.code-block{font-family:var(--font-mono);font-size:12.5px;line-height:1.95;padding:8px 0}
.code-line{
  padding:1px 12px;color:var(--muted);white-space:pre;overflow-x:auto;
  border-left:3px solid transparent;transition:background .2s,border-color .2s,color .2s;
}
.code-line.parked{background:var(--accent-soft);color:var(--ink);border-left-color:var(--line)}
.code-line.live-now{background:var(--accent);color:var(--accent-ink);border-left-color:var(--accent-ink);font-weight:600}

.state-strip{display:flex;gap:8px;flex-wrap:wrap;margin:4px 0 16px}
.state-badge{
  display:flex;align-items:center;gap:7px;background:var(--panel);border:1px solid var(--line);
  border-radius:9px;padding:7px 12px;transition:background .25s,border-color .25s;
}
.state-badge .k{font-size:11px;color:var(--muted);text-transform:uppercase;letter-spacing:.05em}
.state-badge .v{font-family:var(--font-mono);font-weight:700;font-size:14.5px;color:var(--ink)}
.state-badge.flash{background:var(--accent-soft);border-color:var(--accent)}
.state-badge.bad.flash{background:color-mix(in srgb, var(--warn) 18%, transparent);border-color:var(--warn)}

.stage{
  background:var(--panel);border:1px solid var(--line);border-radius:12px;
  padding:16px;margin-bottom:16px;min-height:120px;
}

.log-panel{
  border:1px solid var(--line);border-radius:10px;background:var(--panel);
  max-height:220px;overflow-y:auto;padding:4px 0;
}
.log-entry{
  display:flex;gap:10px;padding:7px 12px;font-size:12.5px;line-height:1.5;
  border-bottom:1px solid var(--line);opacity:0;transform:translateY(3px);
  animation:logIn .25s ease forwards;
}
.log-entry:last-child{border-bottom:none}
.log-entry .n{font-family:var(--font-mono);color:var(--muted);flex:none;min-width:20px}
.log-entry.warn{color:var(--warn)}
.log-entry.warn .n{color:var(--warn)}
@keyframes logIn{to{opacity:1;transform:none}}

/* buffer visualization */
.buffer-row{display:flex;gap:8px;flex-wrap:wrap}
.buffer-slot{
  width:64px;height:64px;border-radius:10px;border:2px dashed var(--line);
  display:flex;align-items:center;justify-content:center;font-family:var(--font-mono);
  font-weight:700;font-size:13px;color:var(--muted);background:var(--bg);position:relative;
  transition:background .2s,border-color .2s,color .2s;
}
.buffer-slot.filled{border-style:solid;border-color:var(--accent);background:var(--accent-soft);color:var(--ink)}
.buffer-slot .idx{position:absolute;top:-8px;left:-8px;font-size:10px;color:var(--muted);background:var(--panel);border:1px solid var(--line);border-radius:999px;padding:0 5px}
.buffer-slot .mark{position:absolute;bottom:-20px;font-size:10.5px;font-family:var(--font-mono);color:var(--accent)}

/* dining philosophers table */
.phil-wrap{display:flex;justify-content:center;padding:6px 0 2px}
.phil-table{position:relative;width:280px;height:280px}
.phil-table .rice{
  position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);
  width:76px;height:76px;border-radius:50%;background:var(--accent-soft);border:1px solid var(--accent);
  display:flex;align-items:center;justify-content:center;font-size:11px;color:var(--accent);font-weight:700;
  text-transform:uppercase;letter-spacing:.05em;text-align:center;
}
.phil{
  position:absolute;width:62px;height:62px;border-radius:50%;
  display:flex;align-items:center;justify-content:center;flex-direction:column;
  font-family:var(--font-mono);font-size:10.5px;font-weight:700;color:#fff;
  box-shadow:0 0 0 3px var(--bg);transition:box-shadow .2s,transform .2s;
}
.phil.thinking{opacity:.55}
.phil.has-left{box-shadow:0 0 0 3px var(--warn)}
.phil.eating{box-shadow:0 0 0 3px #fff,0 0 0 6px var(--accent);transform:scale(1.08)}
.chop{
  position:absolute;width:26px;height:7px;border-radius:4px;background:var(--line);
  transform-origin:center;transition:background .2s,opacity .2s;
}
.chop.taken{background:var(--warn);opacity:.9}

/* readers-writers room */
.rw-room{display:flex;gap:18px;align-items:center;flex-wrap:wrap}
.rw-group{display:flex;flex-direction:column;align-items:center;gap:6px}
.rw-group .label{font-size:11px;color:var(--muted);text-transform:uppercase;letter-spacing:.05em}
.rw-chip{
  width:46px;height:46px;border-radius:50%;display:flex;align-items:center;justify-content:center;
  font-family:var(--font-mono);font-weight:700;font-size:11px;color:#fff;opacity:.3;
  transition:opacity .25s,box-shadow .25s;
}
.rw-chip.active{opacity:1;box-shadow:0 0 0 3px var(--accent-soft)}
.rw-chip.blocked{opacity:1;box-shadow:0 0 0 3px color-mix(in srgb, var(--warn) 35%, transparent)}
.rw-lock{
  font-family:var(--font-mono);font-size:12px;padding:6px 12px;border-radius:999px;
  border:1px solid var(--line);color:var(--muted);background:var(--bg);
}
.rw-lock.locked{border-color:var(--warn);color:var(--warn);background:color-mix(in srgb, var(--warn) 10%, transparent)}
.rw-lock.free{border-color:var(--accent);color:var(--accent)}

/* semaphore queue */
.queue-row{display:flex;align-items:center;gap:8px;flex-wrap:wrap;margin-top:10px}
.queue-row .label{font-size:11px;color:var(--muted);text-transform:uppercase;letter-spacing:.05em}
.queue-chip{
  font-family:var(--font-mono);font-size:12px;font-weight:700;color:#fff;
  padding:5px 10px;border-radius:7px;
}
.queue-empty{font-size:12px;color:var(--muted);font-style:italic}

/* lock visualization (test-and-set) */
.lock-viz{display:flex;align-items:center;gap:14px;justify-content:center;padding:10px 0}
.lock-badge{
  width:74px;height:74px;border-radius:14px;display:flex;align-items:center;justify-content:center;
  font-size:26px;border:2px solid var(--line);background:var(--bg);transition:background .2s,border-color .2s;
}
.lock-badge.held{border-color:var(--warn);background:color-mix(in srgb, var(--warn) 12%, transparent)}
.lock-badge.free{border-color:var(--accent);background:var(--accent-soft)}

.flag-table{font-family:var(--font-mono);font-size:12.5px}

.deadlock-banner{
  margin-top:10px;background:color-mix(in srgb, var(--warn) 14%, transparent);
  border:1px solid var(--warn);color:var(--warn);border-radius:9px;padding:9px 13px;font-size:13px;font-weight:600;
}