/*
 * theme.css — System Design Lab.
 * Direction: a blueprint control room — deep navy ground with a faint drafting
 * grid, amber "signal" packets moving through it, sky blue as the second wire.
 * Precise like Linear, readable like a lab notebook. Opens dark; the light
 * mode is warm drafting paper with the same amber signal.
 */

:root {
  color-scheme: dark;
  --canvas: #0b1120;
  --surface: #111a2e;
  --surface-2: #172239;
  --border: #22304c;
  --border-strong: #4a5d86;
  --ink: #e6ecf7;
  --muted: #94a3c0;
  --accent: #f5a524;
  --accent-hover: #ffb84a;
  --accent-ink: #1c1204;
  --accent-text: #ffbe55;
  --accent-strong: #ffc96e;
  --accent-soft: #2a2213;
  --accent-border: #6b5122;
  --success: #22c55e;
  --success-ink: #05230f;
  --success-soft: #0e2a1b;
  --success-strong: #5fe39a;
  --warning: #fb7a2c;
  --warning-ink: #230e02;
  --warning-soft: #2e1a0e;
  --warning-strong: #ffa46b;
  --danger: #ef4d56;
  --danger-ink: #ffffff;
  --danger-soft: #2f1419;
  --danger-strong: #ff8f96;
  --chart-1: #f5a524;
  --chart-2: #38bdf8;
  --chart-3: #22c55e;
  --chart-4: #a78bfa;
  --chart-5: #f472b6;
  --chart-6: #94a3c0;

  --font-display: "Space Grotesk Variable", ui-sans-serif, system-ui, sans-serif;
  --font-body: "Manrope Variable", ui-sans-serif, system-ui, sans-serif;
  --font-sans: "Manrope Variable", ui-sans-serif, system-ui, sans-serif;
  --font-mono: "JetBrains Mono Variable", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --display-weight: 700;
  --display-tracking: -0.03em;
  --eyebrow-tracking: 0.12em;

  --radius-btn: 0.625rem;
  --radius-card: 1rem;
  --radius-input: 0.625rem;
  --border-w: 1px;
  --btn-weight: 700;
  --card-pad: 1.5rem;
  --shadow-card: 0 1px 0 rgba(255, 255, 255, 0.03) inset, 0 12px 32px -18px rgba(0, 0, 0, 0.7);
  --shadow-raised: 0 18px 50px -20px rgba(0, 0, 0, 0.8);
  --shadow-btn: none;

  --x-sky: #38bdf8;
  --x-sky-soft: #0d2536;
  --x-violet: #a78bfa;
  --x-grid: #15203a;
  --x-stage: #0d1528;
  --x-wire: #2c3d62;
}

html[data-theme="light"] {
  color-scheme: light;
  --canvas: #f5f3ec;
  --surface: #ffffff;
  --surface-2: #ece8dc;
  --border: #ddd7c6;
  --border-strong: #948b72;
  --ink: #131a2a;
  --muted: #586074;
  --accent: #f0a020;
  --accent-hover: #e08f0a;
  --accent-ink: #1c1204;
  --accent-text: #8f5400;
  --accent-strong: #704000;
  --accent-soft: #fcefd2;
  --accent-border: #e9c47a;
  --success: #15803d;
  --success-ink: #ffffff;
  --success-soft: #e0f2e6;
  --success-strong: #11652f;
  --warning: #c2410c;
  --warning-ink: #ffffff;
  --warning-soft: #fbe8dc;
  --warning-strong: #9a3409;
  --danger: #c42b2b;
  --danger-ink: #ffffff;
  --danger-soft: #fbe2e2;
  --danger-strong: #a51f1f;
  --chart-1: #d98a00;
  --chart-2: #0284c7;
  --chart-3: #15803d;
  --chart-4: #7c3aed;
  --chart-5: #db2777;
  --chart-6: #64748b;

  --shadow-card: 0 1px 2px rgba(0, 0, 0, 0.04), 0 10px 30px -20px rgba(0, 0, 0, 0.25);
  --shadow-raised: 0 18px 50px -20px rgba(0, 0, 0, 0.3);

  --x-sky: #0369a1;
  --x-sky-soft: #e0f0fa;
  --x-violet: #6d28d9;
  --x-grid: #e7e2d3;
  --x-stage: #fbfaf6;
  --x-wire: #c9c1aa;
}

/*
 * app.css — System Design Lab's own screens: the blueprint ground, the
 * curriculum "metro" map, and every simulator part (stage, nodes, wires,
 * packets, lanes, stats). Tokens only. Class names avoid Tailwind utility
 * names (ring, empty…) so nothing collides with the compiled utilities.
 */

/* ---------- Ground ---------- */
.blueprint {
  background-color: var(--canvas);
  background-image:
    radial-gradient(60rem 30rem at 85% -10%, color-mix(in srgb, var(--accent) 10%, transparent), transparent 70%),
    radial-gradient(50rem 30rem at -10% 40%, color-mix(in srgb, var(--x-sky) 8%, transparent), transparent 70%),
    linear-gradient(var(--x-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--x-grid) 1px, transparent 1px);
  background-size: auto, auto, 2rem 2rem, 2rem 2rem;
  background-attachment: fixed, fixed, scroll, scroll;
  font-family: var(--font-body);
}
.font-display { font-family: var(--font-display); letter-spacing: var(--display-tracking); }
.kicker {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: var(--eyebrow-tracking);
  text-transform: uppercase;
  color: var(--accent-text);
}
.text-sky { color: var(--x-sky); }
.signal { color: var(--accent-text); }
.brand-mark { color: var(--accent); }

/* ---------- Top bar ---------- */
.topbar {
  border-bottom: 1px solid color-mix(in srgb, var(--border) 70%, transparent);
  background: color-mix(in srgb, var(--canvas) 82%, transparent);
  backdrop-filter: blur(10px);
}
.progress-pill {
  display: inline-flex; align-items: center; gap: 0.5rem;
  border: 1px solid var(--border); border-radius: 999px;
  padding: 0.25rem 0.75rem; font-family: var(--font-mono); font-size: 0.75rem; color: var(--muted);
  background: var(--surface);
}
.progress-pill b { color: var(--ink); }
.pring { width: 1rem; height: 1rem; border-radius: 999px;
  background: conic-gradient(var(--success) calc(var(--p, 0) * 1%), var(--surface-2) 0); }

/* ---------- Hero stage ---------- */
.hero-stage {
  position: relative; border: 1px solid var(--border); border-radius: 1.5rem;
  background: color-mix(in srgb, var(--x-stage) 88%, transparent);
  box-shadow: var(--shadow-raised);
  padding: 1.5rem;
}
.hero-grid { position: relative; display: grid; grid-template-columns: 1fr 1fr; gap: 3rem 2.5rem; padding: 0.5rem; }
.hero-grid .node { min-height: 6rem; }

/* ---------- Metro map (curriculum) ---------- */
.metro { position: relative; display: grid; gap: 0.75rem; }
.metro::before {
  content: ""; position: absolute; left: 1.375rem; top: 1.5rem; bottom: 1.5rem; width: 3px; border-radius: 3px;
  background: var(--line, var(--accent));
}
.metro-advanced { --line: var(--x-sky); }
.stop { position: relative; padding-left: 3.5rem; }
.stop-dot {
  position: absolute; left: 0.625rem; top: 50%; transform: translateY(-50%);
  width: 1.75rem; height: 1.75rem; border-radius: 999px; display: grid; place-items: center;
  background: var(--canvas); border: 3px solid var(--line, var(--accent));
  font-family: var(--font-mono); font-size: 0.625rem; font-weight: 700; color: var(--ink);
}
.stop-dot .icon { width: 0.875rem; height: 0.875rem; display: none; }
.stop[data-done] .stop-dot { background: var(--success); border-color: var(--success); color: var(--success-ink); }
.stop[data-done] .stop-dot .num { display: none; }
.stop[data-done] .stop-dot .icon { display: block; }
.stop-card {
  display: flex; align-items: center; gap: 1rem; padding: 1rem 1.25rem;
  border: 1px solid var(--border); border-radius: var(--radius-card); background: var(--surface);
  transition: border-color 160ms ease, transform 200ms ease, background-color 160ms ease;
}
.stop-card:hover { border-color: var(--line, var(--accent)); transform: translateX(4px); text-decoration: none; }
.stop-ico {
  flex-shrink: 0; width: 2.5rem; height: 2.5rem; border-radius: 0.75rem; display: grid; place-items: center;
  background: color-mix(in srgb, var(--line, var(--accent)) 14%, transparent); color: var(--line, var(--accent));
}
.metro-advanced .stop-ico { color: var(--x-sky); }

/* ---------- Simulator shell ---------- */
.sim {
  position: relative; border: 1px solid var(--border); border-radius: 1.25rem;
  background: var(--x-stage); padding: 1.25rem; box-shadow: var(--shadow-card);
}
@media (min-width: 48rem) { .sim { padding: 1.75rem; } }
.sim > * + * { margin-top: 1.25rem; }
.sim-loading { display: grid; place-items: center; min-height: 18rem; color: var(--muted); font-family: var(--font-mono); font-size: 0.875rem; }

.ctrls { display: grid; gap: 1rem; grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr)); align-items: end; }
/* Buttons: two per row on a phone (an odd last one takes the whole row), one
   tidy row of fixed-width buttons on a wider screen. */
.btnrow { display: grid; gap: 0.5rem; grid-template-columns: repeat(2, minmax(0, 1fr)); }
.btnrow > :last-child:nth-child(odd) { grid-column: 1 / -1; }
@media (min-width: 48rem) {
  .ctrls > .btnrow { grid-column: 1 / -1; grid-template-columns: none; grid-auto-flow: column; grid-auto-columns: minmax(0, 13rem); justify-content: start; }
  .ctrls > .btnrow > :last-child:nth-child(odd) { grid-column: auto; }
}
.ctrl-label { display: block; margin-bottom: 0.375rem; font-size: 0.75rem; font-weight: 600; color: var(--muted); }

.seg {
  display: grid; grid-auto-flow: column; grid-auto-columns: minmax(0, 1fr); gap: 0.25rem;
  padding: 0.25rem; border: 1px solid var(--border); border-radius: 0.75rem; background: var(--surface);
}
.seg button {
  min-height: 2.25rem; padding: 0.375rem 0.5rem; border-radius: 0.5rem; font-size: 0.8125rem; font-weight: 600;
  line-height: 1.15; color: var(--muted); text-align: center; transition: background-color 150ms ease, color 150ms ease;
}
.seg button:hover { color: var(--ink); }
.seg button[aria-pressed="true"] { background: var(--accent); color: var(--accent-ink); }

.slider { display: block; }
.slider-top { display: flex; align-items: baseline; justify-content: space-between; gap: 0.75rem; margin-bottom: 0.375rem; font-size: 0.75rem; font-weight: 600; color: var(--muted); }
.slider output { font-family: var(--font-mono); color: var(--ink); }
.slider input[type="range"] { width: 100%; accent-color: var(--accent); }

/* ---------- Stage, nodes, wires, packets ---------- */
.stage { position: relative; padding: 0.5rem 0; }
.stage > .wires { position: absolute; inset: 0; width: 100%; height: 100%; pointer-events: none; z-index: 0; overflow: visible; }
.wire { stroke: var(--x-wire); stroke-width: 2; stroke-dasharray: 3 7; stroke-linecap: round; animation: wire-flow 1.2s linear infinite; }
.wire-off { opacity: 0.18; }
.wire-cut { stroke: var(--danger); stroke-dasharray: 2 10; animation: none; opacity: 0.9; }
.wire-hot { stroke: var(--accent); opacity: 0.7; }
@keyframes wire-flow { to { stroke-dashoffset: -20; } }

.node {
  position: relative; z-index: 1; min-width: 0;
  display: flex; flex-direction: column; align-items: center; gap: 0.25rem; text-align: center;
  padding: 0.875rem 0.625rem; border: 1px solid var(--border-strong); border-radius: 0.875rem;
  background: var(--surface); transition: border-color 200ms ease, opacity 200ms ease, transform 200ms ease;
}
.node > .icon { width: 1.375rem; height: 1.375rem; color: var(--accent-text); }
.node .nt { font-family: var(--font-display); font-weight: 700; font-size: 0.875rem; line-height: 1.15; }
.node .ns { font-size: 0.6875rem; color: var(--muted); line-height: 1.25; }
.node .nv { font-family: var(--font-mono); font-size: 0.8125rem; color: var(--ink); word-break: break-all; }
.node.is-dead { opacity: 0.45; border-style: dashed; border-color: var(--danger); }
.node.is-dead > .icon { color: var(--danger-strong); }
.node.is-owner { border-color: var(--accent); box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 22%, transparent); }
.node-sky > .icon { color: var(--x-sky); }
@media (max-width: 30rem) {
  .node { padding: 0.625rem 0.375rem; border-radius: 0.75rem; }
  .node .nt { font-size: 0.75rem; }
  .node .ns { font-size: 0.625rem; }
  .node > .icon { width: 1.125rem; height: 1.125rem; }
}

.pkt {
  position: absolute; top: 0; left: 0; z-index: 5; pointer-events: none; white-space: nowrap;
  min-width: 0.75rem; min-height: 0.75rem; padding: 0.125rem 0.4rem; border-radius: 999px;
  font-family: var(--font-mono); font-size: 0.625rem; font-weight: 700; line-height: 1.3;
  background: var(--accent); color: var(--accent-ink);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 22%, transparent), 0 0 18px color-mix(in srgb, var(--accent) 55%, transparent);
  will-change: transform;
}
.pkt:empty { width: 0.75rem; height: 0.75rem; padding: 0; }
.pkt-sky { background: var(--x-sky); color: var(--canvas); box-shadow: 0 0 0 3px color-mix(in srgb, var(--x-sky) 22%, transparent), 0 0 18px color-mix(in srgb, var(--x-sky) 55%, transparent); }
.pkt-ok { background: var(--success); color: var(--success-ink); box-shadow: 0 0 0 3px color-mix(in srgb, var(--success) 22%, transparent), 0 0 18px color-mix(in srgb, var(--success) 50%, transparent); }
.pkt-bad { background: var(--danger); color: var(--danger-ink); box-shadow: 0 0 0 3px color-mix(in srgb, var(--danger) 25%, transparent), 0 0 18px color-mix(in srgb, var(--danger) 55%, transparent); }
.pkt-warn { background: var(--warning); color: var(--warning-ink); box-shadow: 0 0 0 3px color-mix(in srgb, var(--warning) 22%, transparent), 0 0 16px color-mix(in srgb, var(--warning) 50%, transparent); }
.pkt-muted { background: var(--surface-2); color: var(--muted); box-shadow: 0 0 0 1px var(--border-strong); }
.pkt-violet { background: var(--x-violet); color: var(--canvas); box-shadow: 0 0 16px color-mix(in srgb, var(--x-violet) 50%, transparent); }

.flash-ok { animation: flash-ok 700ms ease-out; }
.flash-bad { animation: flash-bad 800ms ease-out; }
.flash-warn { animation: flash-warn 700ms ease-out; }
@keyframes flash-ok { 0% { box-shadow: 0 0 0 0 color-mix(in srgb, var(--success) 70%, transparent); border-color: var(--success); } 100% { box-shadow: 0 0 0 14px transparent; } }
@keyframes flash-bad { 0% { box-shadow: 0 0 0 0 color-mix(in srgb, var(--danger) 75%, transparent); border-color: var(--danger); transform: translateX(-3px); } 20% { transform: translateX(3px); } 40% { transform: translateX(-2px); } 60% { transform: none; } 100% { box-shadow: 0 0 0 16px transparent; } }
@keyframes flash-warn { 0% { box-shadow: 0 0 0 0 color-mix(in srgb, var(--warning) 70%, transparent); border-color: var(--warning); } 100% { box-shadow: 0 0 0 14px transparent; } }

/* ---------- Stats, narration, logs ---------- */
.stats { display: grid; gap: 0.5rem; grid-template-columns: repeat(2, minmax(0, 1fr)); }
@media (min-width: 40rem) { .stats { grid-template-columns: repeat(4, minmax(0, 1fr)); } }
.stat { border: 1px solid var(--border); border-radius: 0.75rem; background: var(--surface); padding: 0.625rem 0.875rem; min-width: 0; }
.stat-v { display: block; font-family: var(--font-display); font-weight: 700; font-size: 1.5rem; line-height: 1.1; font-variant-numeric: tabular-nums; }
.stat-k { display: block; margin-top: 0.125rem; font-size: 0.6875rem; color: var(--muted); }
.stat.is-bad .stat-v { color: var(--danger-strong); }
.stat.is-ok .stat-v { color: var(--success-strong); }
.stat.is-warn .stat-v { color: var(--warning-strong); }
.stat .bump { animation: bump 380ms ease-out; display: inline-block; }
@keyframes bump { 0% { transform: scale(1.35); } 100% { transform: none; } }

.narrate {
  display: flex; gap: 0.75rem; align-items: flex-start; padding: 0.75rem 1rem;
  border-radius: 0.75rem; border: 1px solid var(--border); border-left: 3px solid var(--x-sky);
  background: var(--surface); font-size: 0.9375rem; line-height: 1.5;
}
.narrate .icon { flex-shrink: 0; margin-top: 0.15rem; color: var(--x-sky); }
.narrate.is-bad { border-left-color: var(--danger); background: var(--danger-soft); color: var(--danger-strong); }
.narrate.is-bad .icon { color: var(--danger-strong); }
.narrate.is-ok { border-left-color: var(--success); background: var(--success-soft); color: var(--success-strong); }
.narrate.is-ok .icon { color: var(--success-strong); }
.narrate.is-warn { border-left-color: var(--warning); background: var(--warning-soft); color: var(--warning-strong); }
.narrate.is-warn .icon { color: var(--warning-strong); }
.narrate.pop { animation: fade-up 260ms ease-out; }

.panel { border: 1px solid var(--border); border-radius: 0.875rem; background: var(--surface); padding: 0.875rem; min-width: 0; position: relative; }
.panel-h { display: flex; align-items: center; justify-content: space-between; gap: 0.5rem; margin-bottom: 0.5rem; font-size: 0.75rem; font-weight: 700; color: var(--muted); text-transform: uppercase; letter-spacing: 0.06em; }
.panel.is-off > :not(.panel-h):not(.off-note) { filter: blur(3px); opacity: 0.35; }
.off-note { position: absolute; inset: 2.25rem 0.75rem 0.75rem; display: grid; place-items: center; text-align: center; font-size: 0.8125rem; color: var(--muted); z-index: 2; }

.log { font-family: var(--font-mono); font-size: 0.6875rem; line-height: 1.5; max-height: 11rem; overflow-y: auto; display: grid; gap: 0.125rem; }
.log li { display: flex; gap: 0.5rem; padding: 0.125rem 0.375rem; border-radius: 0.375rem; animation: fade-up 220ms ease-out; }
.log li .t { color: var(--muted); flex-shrink: 0; }
.log li.is-bad { background: var(--danger-soft); color: var(--danger-strong); }
.log li.is-ok { color: var(--success-strong); }
.log li.is-warn { background: var(--warning-soft); color: var(--warning-strong); }

/* ---------- Idempotency ---------- */
.rows { display: grid; gap: 0.25rem; width: 100%; margin-top: 0.375rem; max-height: 12rem; overflow-y: auto; }
.rows li { font-family: var(--font-mono); font-size: 0.625rem; padding: 0.25rem 0.375rem; border-radius: 0.375rem; background: var(--surface-2); text-align: left; animation: fade-up 260ms ease-out; }
.rows li.is-dup { background: var(--danger-soft); color: var(--danger-strong); }
.rows li.is-ok { background: var(--success-soft); color: var(--success-strong); }
.keys { display: flex; flex-wrap: wrap; justify-content: center; gap: 0.25rem; margin-top: 0.25rem; }
.keychip { font-family: var(--font-mono); font-size: 0.625rem; padding: 0.0625rem 0.375rem; border-radius: 0.375rem; background: var(--x-sky-soft); color: var(--x-sky); border: 1px solid color-mix(in srgb, var(--x-sky) 40%, transparent); animation: fade-up 220ms ease-out; }
.keychip.hit { animation: flash-warn 700ms ease-out; border-color: var(--warning); }
.keystore { width: 100%; margin-top: 0.5rem; padding: 0.5rem; border-radius: 0.625rem; border: 1px dashed var(--border-strong); }
.keystore-h { display: block; font-size: 0.625rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted); }
.keystore.is-off { opacity: 0.35; }

/* ---------- Retries ---------- */
.lanes { display: grid; gap: 0.375rem; }
.lane { display: grid; grid-template-columns: 2.25rem minmax(0, 1fr) 3.25rem; align-items: center; gap: 0.5rem; }
.lane-k { font-family: var(--font-mono); font-size: 0.6875rem; color: var(--muted); }
.lane-track { position: relative; height: 1.125rem; border-radius: 999px; background: var(--surface); border: 1px solid var(--border); overflow: hidden; }
.lane-end { font-family: var(--font-mono); font-size: 0.625rem; font-weight: 700; text-align: right; }
.lane-end.ok { color: var(--success-strong); }
.lane-end.dlq { color: var(--danger-strong); }
.outage-band { position: absolute; top: 0; bottom: 0; background: color-mix(in srgb, var(--danger) 18%, transparent); }
.tdot { position: absolute; top: 50%; width: 0.625rem; height: 0.625rem; margin: -0.3125rem 0 0 -0.3125rem; border-radius: 999px; animation: dot-in 300ms ease-out; }
.tdot.ok { background: var(--success); }
.tdot.bad { background: var(--danger); }
@keyframes dot-in { from { transform: scale(2.4); } to { transform: none; } }
.loadbars { display: grid; grid-template-columns: repeat(24, minmax(0, 1fr)); align-items: end; gap: 2px; height: 4.5rem; padding-left: 2.75rem; padding-right: 3.75rem; }
.loadbars .bar { border-radius: 3px 3px 0 0; background: var(--x-sky); min-height: 2px; transition: height 200ms ease; }
.loadbars .bar.hot { background: var(--danger); }
.dlq-list { display: flex; flex-wrap: wrap; gap: 0.25rem; min-height: 1.5rem; }
.dlq-list li { font-family: var(--font-mono); font-size: 0.6875rem; padding: 0.0625rem 0.5rem; border-radius: 0.375rem; background: var(--danger-soft); color: var(--danger-strong); animation: fade-up 220ms ease-out; }

/* ---------- Rate limits ---------- */
.qbox { display: flex; flex-wrap: wrap; align-content: flex-end; justify-content: center; gap: 2px; width: 100%; min-height: 4rem; padding: 0.25rem; border-radius: 0.5rem; background: var(--surface-2); }
.qbox i { width: 0.5rem; height: 0.5rem; border-radius: 2px; background: var(--accent); animation: dot-in 200ms ease-out; }
.tokens { display: flex; flex-wrap: wrap; justify-content: center; gap: 3px; margin-top: 0.25rem; }
.tokens i { width: 0.5rem; height: 0.5rem; border-radius: 999px; border: 1px solid var(--success); }
.tokens i.full { background: var(--success); }

/* ---------- Source of truth ---------- */
.tri { display: grid; grid-template-columns: 1fr 1fr; gap: 2.5rem 1.5rem; }
.tri > .tri-top { grid-column: 1 / -1; justify-self: center; width: min(100%, 15rem); }
.owner-tag { font-size: 0.625rem; font-weight: 700; padding: 0.0625rem 0.5rem; border-radius: 999px; background: var(--accent); color: var(--accent-ink); }
.lock-tag { font-size: 0.625rem; font-weight: 700; padding: 0.0625rem 0.5rem; border-radius: 999px; background: var(--surface-2); color: var(--muted); }

/* ---------- Sync vs async ---------- */
.chat { display: grid; gap: 0.5rem; align-content: start; min-height: 14rem; }
.bubble { max-width: 90%; padding: 0.5rem 0.75rem; border-radius: 0.875rem; font-size: 0.8125rem; line-height: 1.4; animation: fade-up 240ms ease-out; }
.bubble.me { justify-self: end; background: var(--x-sky-soft); color: var(--ink); border-bottom-right-radius: 0.25rem; }
.bubble.bot { justify-self: start; background: var(--surface-2); border-bottom-left-radius: 0.25rem; }
.bubble.bad { background: var(--danger-soft); color: var(--danger-strong); }
.bubble.ok { background: var(--success-soft); color: var(--success-strong); }
.typing { display: inline-flex; gap: 3px; }
.typing i { width: 6px; height: 6px; border-radius: 999px; background: var(--muted); animation: typing 1s infinite ease-in-out; }
.typing i:nth-child(2) { animation-delay: 0.15s; }
.typing i:nth-child(3) { animation-delay: 0.3s; }
@keyframes typing { 0%, 100% { transform: translateY(0); opacity: 0.4; } 50% { transform: translateY(-3px); opacity: 1; } }
.tl { position: relative; display: grid; gap: 0.75rem; }
.tl-row { display: grid; grid-template-columns: 4.5rem minmax(0, 1fr); gap: 0.5rem; align-items: center; }
.tl-k { font-size: 0.6875rem; font-weight: 700; color: var(--muted); }
.tl-track { position: relative; height: 1.75rem; border-radius: 0.5rem; background: var(--surface); border: 1px solid var(--border); overflow: hidden; }
.tl-seg { position: absolute; top: 3px; bottom: 3px; border-radius: 0.375rem; font-size: 0.5625rem; font-weight: 700; display: flex; align-items: center; padding: 0 0.375rem; overflow: hidden; white-space: nowrap; }
.tl-seg.wait { background: color-mix(in srgb, var(--accent) 30%, transparent); color: var(--ink); }
.tl-seg.ok { background: var(--success); color: var(--success-ink); }
.tl-seg.bad { background: var(--danger); color: var(--danger-ink); }
.tl-seg.step { background: color-mix(in srgb, var(--x-sky) 35%, transparent); color: var(--ink); }
.tl-seg.step.done { background: var(--x-sky); color: var(--canvas); }
.tl-mark { position: absolute; top: -0.25rem; bottom: -0.25rem; width: 2px; background: var(--danger); z-index: 2; }
.tl-mark span { position: absolute; top: -1.1rem; left: 0; transform: translateX(-50%); font-size: 0.5625rem; font-weight: 700; color: var(--danger-strong); white-space: nowrap; }
.tl-axis { display: grid; grid-template-columns: 4.5rem minmax(0, 1fr); gap: 0.5rem; font-family: var(--font-mono); font-size: 0.5625rem; color: var(--muted); }
.tl-axis > div { display: flex; justify-content: space-between; }

/* ---------- Auth ---------- */
.choice { display: grid; gap: 0.5rem; grid-template-columns: repeat(auto-fit, minmax(10rem, 1fr)); }
.choice button { display: flex; flex-direction: column; align-items: flex-start; gap: 0.25rem; padding: 0.75rem; border-radius: 0.75rem; border: 1px solid var(--border); background: var(--surface); text-align: left; font-size: 0.8125rem; font-weight: 600; transition: border-color 150ms ease, background-color 150ms ease; }
.choice button span { font-size: 0.6875rem; font-weight: 500; color: var(--muted); }
.choice button[aria-pressed="true"] { border-color: var(--accent); background: var(--accent-soft); color: var(--accent-strong); }
.codebox { font-family: var(--font-mono); font-size: 0.75rem; line-height: 1.6; padding: 0.75rem; border-radius: 0.625rem; background: var(--canvas); border: 1px solid var(--border); overflow-x: auto; white-space: pre; }
.codebox mark { background: var(--danger-soft); color: var(--danger-strong); border-radius: 3px; padding: 0 2px; }
.codebox .ok { color: var(--success-strong); }
.codebox .bad { color: var(--danger-strong); }
.blast li { display: flex; align-items: center; gap: 0.5rem; padding: 0.375rem 0; font-size: 0.8125rem; border-bottom: 1px solid var(--border); }
.blast li:last-child { border-bottom: 0; }
.blast li.can { color: var(--danger-strong); }
.blast li.cannot { color: var(--muted); }
.blast li.cannot .icon { color: var(--success-strong); }

/* ---------- Observability ---------- */
.mbars { display: grid; grid-template-columns: repeat(30, minmax(0, 1fr)); align-items: end; gap: 2px; height: 5rem; }
.mbars i { border-radius: 2px 2px 0 0; background: var(--success); min-height: 3px; animation: dot-in 200ms ease-out; }
.mbars i.bad { background: var(--danger); }
.mbars i.slow { background: var(--warning); }
.alert-box { display: grid; place-items: center; text-align: center; min-height: 6rem; gap: 0.25rem; border-radius: 0.625rem; padding: 0.75rem; font-size: 0.8125rem; }
.alert-box.quiet { background: var(--surface-2); color: var(--muted); }
.alert-box.firing { background: var(--danger-soft); color: var(--danger-strong); animation: alarm 1.2s ease-in-out infinite; }
@keyframes alarm { 50% { box-shadow: 0 0 0 4px color-mix(in srgb, var(--danger) 40%, transparent); } }
.client-msg { display: flex; gap: 0.75rem; align-items: flex-start; padding: 0.875rem 1rem; border-radius: 0.875rem; background: var(--warning-soft); color: var(--warning-strong); animation: fade-up 300ms ease-out; }

/* ---------- Caching ---------- */
.slots { display: grid; gap: 0.25rem; width: 100%; margin-top: 0.375rem; }
.slot { position: relative; display: flex; justify-content: space-between; gap: 0.25rem; padding: 0.25rem 0.375rem; border-radius: 0.375rem; background: var(--surface-2); font-family: var(--font-mono); font-size: 0.625rem; overflow: hidden; text-align: left; }
.slot.is-empty { color: var(--muted); opacity: 0.6; }
.slot .ttl { position: absolute; left: 0; bottom: 0; height: 2px; background: var(--accent); }
.slot.stale { background: var(--warning-soft); color: var(--warning-strong); }

/* ---------- Load balancing ---------- */
.srv { display: grid; grid-template-columns: minmax(0, 1fr) auto; align-items: center; gap: 0.5rem; padding: 0.5rem 0.625rem; border: 1px solid var(--border-strong); border-radius: 0.75rem; background: var(--surface); position: relative; z-index: 1; transition: opacity 200ms ease, border-color 200ms ease; }
.srv.is-dead { opacity: 0.45; border-style: dashed; border-color: var(--danger); }
.srv.is-out { box-shadow: inset 3px 0 0 var(--warning); }
.slots-row { display: flex; gap: 3px; margin-top: 0.25rem; }
.slots-row i { width: 0.75rem; height: 0.5rem; border-radius: 2px; background: var(--surface-2); border: 1px solid var(--border-strong); transition: background-color 120ms ease; }
.slots-row i.busy { background: var(--accent); border-color: var(--accent); }
.slots-row i.heavy { background: var(--x-violet); border-color: var(--x-violet); }

/* ---------- Sharding ---------- */
.hashring { width: 100%; max-width: 18rem; aspect-ratio: 1; margin-inline: auto; display: block; }
.hashring .track { fill: none; stroke: var(--border-strong); stroke-width: 2; }
.hashring .ktick { stroke-width: 3; stroke-linecap: round; transition: stroke 400ms ease; stroke: var(--c); }
.hashring .spoint { stroke: var(--x-stage); stroke-width: 2; fill: var(--c); }
.srow { display: grid; grid-template-columns: 3rem minmax(0, 1fr); gap: 0.5rem; align-items: start; padding: 0.375rem 0; border-bottom: 1px solid var(--border); }
.srow:last-child { border-bottom: 0; }
.srow-k { display: flex; align-items: center; gap: 0.375rem; font-family: var(--font-mono); font-size: 0.75rem; font-weight: 700; padding-top: 0.125rem; }
.srow-k i { width: 0.625rem; height: 0.625rem; border-radius: 999px; background: var(--c); }
.kchips { display: flex; flex-wrap: wrap; gap: 0.25rem; min-height: 1.5rem; }
.kchip { font-family: var(--font-mono); font-size: 0.625rem; padding: 0.0625rem 0.375rem; border-radius: 0.375rem; background: var(--surface-2); border: 1px solid var(--border); }
.kchip.moved { border-color: var(--accent); background: var(--accent-soft); color: var(--accent-strong); }
.c1 { --c: var(--chart-1); } .c2 { --c: var(--chart-2); } .c3 { --c: var(--chart-3); }
.c4 { --c: var(--chart-4); } .c5 { --c: var(--chart-5); } .c6 { --c: var(--chart-6); }

/* ---------- Replication ---------- */
.region { font-family: var(--font-mono); font-size: 0.625rem; color: var(--muted); text-transform: uppercase; letter-spacing: 0.08em; }
.dbval { font-family: var(--font-display); font-weight: 700; font-size: 1.25rem; font-variant-numeric: tabular-nums; }
.dbval.diverged { color: var(--warning-strong); }

/* ---------- Consensus ---------- */
.raft { position: relative; width: 100%; max-width: 30rem; aspect-ratio: 1 / 0.92; margin-inline: auto; }
.raft .node { position: absolute; width: 6.25rem; transform: translate(-50%, -50%); padding: 0.5rem; gap: 0.125rem; }
.raft .node.is-leader { border-color: var(--accent); box-shadow: 0 0 0 4px color-mix(in srgb, var(--accent) 22%, transparent), 0 0 30px color-mix(in srgb, var(--accent) 30%, transparent); }
.raft .node.is-candidate { border-color: var(--x-sky); }
.role { font-size: 0.5625rem; font-weight: 800; text-transform: uppercase; letter-spacing: 0.08em; color: var(--muted); }
.is-leader .role { color: var(--accent-text); }
.is-candidate .role { color: var(--x-sky); }
.tbar { width: 100%; height: 3px; border-radius: 3px; background: var(--surface-2); overflow: hidden; }
.tbar i { display: block; height: 100%; background: var(--x-sky); }
.rlog { display: flex; gap: 2px; justify-content: center; min-height: 0.5rem; }
.rlog i { width: 0.5rem; height: 0.5rem; border-radius: 2px; border: 1px solid var(--accent); }
.rlog i.c { background: var(--accent); }
@media (max-width: 30rem) { .raft .node { width: 4.75rem; } .raft .node .ns { display: none; } }

/* ---------- Microservices ---------- */
.ms-grid { display: grid; gap: 1.25rem 1rem; grid-template-columns: repeat(4, minmax(0, 1fr)); align-items: center; }
.breaker { font-size: 0.5625rem; font-weight: 800; padding: 0.0625rem 0.375rem; border-radius: 999px; text-transform: uppercase; letter-spacing: 0.06em; }
.breaker.closed { background: var(--success-soft); color: var(--success-strong); }
.breaker.open { background: var(--danger-soft); color: var(--danger-strong); }
.breaker.half { background: var(--warning-soft); color: var(--warning-strong); }
.mods { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 0.375rem; width: 100%; margin-top: 0.375rem; }
.mods span { font-size: 0.625rem; padding: 0.25rem; border-radius: 0.375rem; background: var(--surface-2); }
.mods span.sick { background: var(--danger-soft); color: var(--danger-strong); }

/* ---------- Lab page: try-this, quiz ---------- */
.try-item { display: flex; align-items: flex-start; gap: 0.75rem; width: 100%; padding: 0.75rem; border-radius: 0.75rem; text-align: left; border: 1px solid transparent; transition: background-color 150ms ease, border-color 150ms ease; }
.try-item:hover { background: var(--surface-2); }
.try-item .tick { flex-shrink: 0; width: 1.375rem; height: 1.375rem; border-radius: 999px; border: 2px solid var(--border-strong); display: grid; place-items: center; margin-top: 0.0625rem; }
.try-item .tick .icon { width: 0.75rem; height: 0.75rem; opacity: 0; }
.try-item[aria-pressed="true"] { border-color: color-mix(in srgb, var(--success) 40%, transparent); background: var(--success-soft); }
.try-item[aria-pressed="true"] .tick { background: var(--success); border-color: var(--success); color: var(--success-ink); }
.try-item[aria-pressed="true"] .tick .icon { opacity: 1; }
.try-item[aria-pressed="true"] .try-text { color: var(--muted); text-decoration: line-through; text-decoration-color: var(--success); }

.idea { border-left: 2px solid var(--accent); padding-left: 1rem; }
.pabbly-band { border: 1px solid var(--accent-border); border-radius: 1.25rem; background: linear-gradient(135deg, var(--accent-soft), color-mix(in srgb, var(--accent-soft) 40%, var(--surface))); }

.quiz-opt { display: flex; align-items: center; gap: 0.75rem; width: 100%; padding: 0.75rem 1rem; text-align: left; border-radius: 0.75rem; border: 1px solid var(--border-strong); background: var(--surface); font-size: 0.9375rem; transition: border-color 150ms ease, background-color 150ms ease; }
.quiz-opt:hover:not(:disabled) { border-color: var(--accent); }
.quiz-opt .letter { flex-shrink: 0; width: 1.5rem; height: 1.5rem; border-radius: 0.375rem; display: grid; place-items: center; font-family: var(--font-mono); font-size: 0.75rem; font-weight: 700; background: var(--surface-2); color: var(--muted); }
.quiz-opt.is-right { border-color: var(--success); background: var(--success-soft); color: var(--success-strong); }
.quiz-opt.is-right .letter { background: var(--success); color: var(--success-ink); }
.quiz-opt.is-wrong { border-color: var(--danger); background: var(--danger-soft); color: var(--danger-strong); animation: flash-bad 600ms ease-out; }
.quiz-opt:disabled { cursor: default; }
.quiz-why { padding: 0.75rem 1rem; border-radius: 0.75rem; background: var(--surface-2); font-size: 0.875rem; color: var(--muted); animation: fade-up 240ms ease-out; }
.quiz-done { animation: fade-up 300ms ease-out; }

.chan { display: flex; align-items: center; gap: 0.75rem; padding: 0.875rem 1rem; border-radius: 0.875rem; border: 1px solid var(--border); background: var(--surface); transition: border-color 150ms ease; }
.chan:hover { border-color: var(--x-sky); text-decoration: none; }
.chan .icon { color: var(--x-sky); }

html.reduced-motion .wire { animation: none; }
html.reduced-motion .pkt { display: none; }