:root {
  --bg: #efe3cc;
  --surface: #fbf5ea;
  --surface-2: #f4ead7;
  --ink: #2b1d10;
  --muted: #5f4a33;
  --line: #decdae;
  --accent: #1e56d6;
  --accent-text: #1a47b3;
  --danger: #e5322d;
  --danger-text: #a3221c;
  --run-bg: #e3e9f8;
  --lock-bg: #f8e0da;
  --radius: 14px;
  --f-head: "Space Grotesk", ui-sans-serif, system-ui, sans-serif;
  --f-body: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  --f-mono: "JetBrains Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  color-scheme: light;
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 400 16px/1.55 var(--f-body);
  -webkit-font-smoothing: antialiased;
}
.mono, code, pre { font-family: var(--f-mono); }
code { font-size: .88em; }
a { color: var(--accent-text); text-underline-offset: 3px; }
a:hover { color: var(--ink); }
:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; border-radius: 4px; }

.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
.skip { position: absolute; left: 16px; top: -60px; background: var(--ink); color: var(--surface); padding: 8px 14px; border-radius: 8px; z-index: 10; }
.skip:focus { top: 12px; }

.wrap { max-width: 1320px; margin-inline: auto; padding-inline: clamp(16px, 3vw, 32px); }

/* ---------- header ---------- */
.top { padding-block: clamp(28px, 5vw, 56px) 24px; }
.eyebrow {
  margin: 0 0 10px;
  font: 500 12px/1.4 var(--f-mono);
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--muted);
}
.topbar { display: flex; align-items: baseline; justify-content: space-between; gap: 4px 16px; margin: 0 0 10px; }
.topbar .eyebrow { margin: 0; }
.lang-switch { display: inline-flex; align-items: baseline; flex: none; font: 400 12px/1.4 var(--f-mono); letter-spacing: .06em; color: var(--muted); }
.lang-switch button {
  font: inherit; letter-spacing: inherit; color: inherit;
  background: none; border: 0; margin: 0; padding: 6px 5px; cursor: pointer;
  border-radius: 4px;
}
.lang-switch button:hover { color: var(--ink); }
.lang-switch button[aria-pressed="true"] { font-weight: 700; color: var(--ink); text-decoration: underline; text-underline-offset: 3px; text-decoration-thickness: 1.5px; }
.lang-switch span { padding: 0 1px; }

h1 {
  margin: 0;
  font: 700 clamp(32px, 3.7vw, 52px)/1.04 var(--f-head);
  letter-spacing: -.025em;
  text-wrap: balance;
}
h1 span { display: block; color: var(--muted); font-weight: 500; }
@media (min-width: 1000px) {
  .top { display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(0, 1fr); column-gap: 48px; align-items: end; }
  .top .topbar { grid-column: 1 / -1; }
  .top h1 { grid-column: 1; grid-row: 2 / span 2; align-self: end; }
  .top .lead { grid-column: 2; margin-top: 0; }
  .top .honesty { grid-column: 2; }
}
.lead { margin: 16px 0 0; max-width: 62ch; font-size: clamp(16px, 1.3vw, 18px); color: var(--ink); }
.honesty {
  display: grid; grid-template-columns: auto minmax(0, 1fr); align-items: start; gap: 4px 10px;
  margin: 18px 0 0;
  padding: 10px 14px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 10px;
  font-size: 14px;
  width: fit-content; max-width: 100%;
}
.honesty svg { color: var(--accent-text); margin-top: 3px; }
.honesty a { grid-column: 2; justify-self: start; }
.honesty a { font-weight: 600; white-space: nowrap; }

/* ---------- layout ---------- */
.layout {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
  gap: 20px;
  align-items: start;
  padding-bottom: 32px;
}
.col { display: grid; gap: 20px; min-width: 0; }
@media (max-width: 1100px) {
  .layout { grid-template-columns: minmax(0, 1fr); }
}

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  min-width: 0;
}
.card:focus { outline: none; }
.card-head {
  display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap;
  gap: 8px 14px;
  margin-bottom: 14px;
}
h2 {
  margin: 0;
  font: 700 18px/1.2 var(--f-head);
  letter-spacing: -.01em;
}

/* ---------- bench ---------- */
.bench-stage { border-radius: 12px; overflow: hidden; }
#bench { display: block; width: 100%; height: auto; }

.engine-pill {
  margin: 0;
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 12px 6px 10px;
  border-radius: 999px;
  font: 700 13px/1 var(--f-mono);
  letter-spacing: .08em;
  text-transform: uppercase;
  border: 1.5px solid currentColor;
  color: var(--muted);
  background: var(--surface);
  transition: background-color .2s, color .2s;
}
.engine-pill[data-state="running"] { color: var(--accent-text); background: var(--run-bg); }
.engine-pill[data-state="locked"] { color: #fff; background: var(--danger-text); border-color: var(--danger-text); }

.pins-row {
  list-style: none; margin: 14px 0 0; padding: 0;
  display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 8px;
}
.pins-row li {
  display: grid; gap: 2px;
  padding: 8px 10px;
  background: var(--surface-2);
  border: 1px solid var(--line);
  border-radius: 10px;
  min-width: 0;
}
.pins-row .k { font: 700 12px/1.2 var(--f-mono); color: var(--muted); letter-spacing: .06em; }
.pins-row .v { font-size: 16px; font-weight: 700; line-height: 1.3; }
.pins-row .d { font-size: 12.5px; color: var(--muted); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.pins-row .v.high { color: var(--danger-text); }
.pins-row .v.high.good { color: var(--accent-text); }
@media (max-width: 560px) {
  .pins-row { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

/* SVG parts */
.lbl { font: 600 12px var(--f-mono); letter-spacing: .08em; fill: var(--muted); }
.state { font: 700 13px var(--f-mono); letter-spacing: .1em; fill: var(--ink); }
.state.locked { fill: var(--danger-text); }
.state.running { fill: var(--accent-text); }
.silk { font: 500 10px var(--f-mono); fill: #e9dcc3; letter-spacing: .04em; }
.silk-light { font: 600 10px var(--f-mono); fill: #eaf0ff; letter-spacing: .04em; }
.silk-tiny { font: 600 8.5px var(--f-mono); fill: #eaf0ff; }
#relay .silk-tiny[text-anchor] { fill: #e9dcc3; }
.uno-word { font: 700 28px var(--f-head); fill: #efe3cc; letter-spacing: .02em; }
.click-txt { font: 700 13px var(--f-mono); fill: #f4c542; opacity: 0; letter-spacing: .06em; }
.click-txt.show { animation: clickPop .5s ease-out; }
@keyframes clickPop {
  0% { opacity: 1; transform: translateY(0); }
  100% { opacity: 0; transform: translateY(-10px); }
}

.wire { stroke: #c4b18f; stroke-width: 3.5; transition: stroke .15s; }
.wire.bus { stroke: #b39e7b; stroke-width: 2.5; }
.wire.analog { stroke: #1e56d6; stroke-opacity: .55; }
.wire.on { stroke: #d6322b; }
.wire.power.on { stroke: #e0a21b; }
.wire#w-d9.on { stroke: #1e56d6; }
.pin { fill: #4a3a28; stroke: #140d07; stroke-width: 1; }
.pin.high { fill: #f4c542; }
.pin-analog { fill: #1e56d6; }
#relayArm { transition: transform .08s ease-out; }
#ledDome, #ledFlange { transition: fill .12s; }
#ledGlowC { transition: opacity .12s; }
#txLed.on { fill: #f4c542; }
#relayLed.on { fill: #5ad06a; }

.waves { opacity: 0; }
.waves.on { opacity: 1; }
.waves.on .wv { animation: wave .5s ease-in-out infinite alternate; }
.waves.on .wv2 { animation-delay: .25s; }
@keyframes wave { from { opacity: .25; } to { opacity: 1; } }

.puff { animation: drift 3.2s ease-in-out infinite; transform-box: fill-box; transform-origin: center; }
.p2 { animation-delay: -.8s; } .p3 { animation-delay: -1.6s; } .p4 { animation-delay: -2.2s; } .p5 { animation-delay: -2.8s; }
@keyframes drift {
  0% { transform: translate(0, 10px) scale(.7); opacity: 0; }
  40% { opacity: .75; }
  100% { transform: translate(6px, -26px) scale(1.25); opacity: 0; }
}

#lcdCells .cell { fill: rgba(255, 255, 255, .09); }
#lcdCells text { font: 500 21px var(--f-mono); fill: #f1f5ff; }

@media (max-width: 640px) {
  .lbl { font-size: 18px; letter-spacing: .02em; }
  .state { font-size: 19px; letter-spacing: .04em; }
  .silk, .silk-tiny, .silk-light { opacity: .0; }
  .uno-word { font-size: 30px; }
  .pinref { display: none; }
  #lcdCells text { font-size: 23px; font-weight: 700; }
}

/* ---------- controls ---------- */
.loop-meta { margin: 0; font-size: 13px; color: var(--muted); }
.loop-bar { height: 3px; border-radius: 3px; background: var(--line); overflow: hidden; margin: -4px 0 18px; }
.loop-bar span { display: block; height: 100%; width: 0; background: var(--accent); }

.reading { display: flex; align-items: flex-end; justify-content: space-between; gap: 8px 16px; flex-wrap: wrap; }
.reading label { font-weight: 600; font-size: 15px; }
.reading label code { display: block; font-weight: 400; color: var(--muted); font-size: 13px; }
.reading-val { margin: 0; display: flex; align-items: baseline; gap: 6px; }
.reading-val output { font-size: 40px; font-weight: 700; line-height: 1; letter-spacing: -.02em; font-variant-numeric: tabular-nums; min-width: 4ch; text-align: right; }
.reading-val output.over { color: var(--danger-text); }
.reading-val .of { color: var(--muted); font-size: 14px; }

.slider-wrap { position: relative; margin: 18px 0 4px; padding-top: 22px; }
.thr {
  position: absolute; top: 0; bottom: 0;
  left: calc(13px + (100% - 26px) * 0.391);
  width: 0; border-left: 2px dashed var(--danger-text);
  pointer-events: none;
}
.thr span {
  position: absolute; top: -2px; left: 6px;
  font: 700 12px/1 var(--f-mono); color: var(--danger-text);
}

input[type="range"] {
  --p: 17.6%;
  -webkit-appearance: none; appearance: none;
  width: 100%; height: 30px; margin: 0; background: transparent; cursor: pointer;
  display: block;
}
input[type="range"]::-webkit-slider-runnable-track {
  height: 10px; border-radius: 6px;
  background:
    linear-gradient(to right, var(--ink) 0 var(--p), transparent var(--p)),
    linear-gradient(to right, #e3d4b7 0 39.1%, #f1c7bd 39.1%);
}
input[type="range"]::-moz-range-track {
  height: 10px; border-radius: 6px;
  background:
    linear-gradient(to right, var(--ink) 0 var(--p), transparent var(--p)),
    linear-gradient(to right, #e3d4b7 0 39.1%, #f1c7bd 39.1%);
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none; appearance: none;
  width: 26px; height: 26px; margin-top: -8px;
  border-radius: 50%; background: var(--surface); border: 3px solid var(--ink);
  box-shadow: 0 1px 3px rgba(43, 29, 16, .3);
}
input[type="range"]::-moz-range-thumb {
  width: 20px; height: 20px; border-radius: 50%;
  background: var(--surface); border: 3px solid var(--ink);
}
input[type="range"]:focus-visible { outline: 3px solid var(--accent); outline-offset: 4px; }

.scale { display: flex; justify-content: space-between; font-size: 12px; color: var(--muted); }
.hint { margin: 10px 0 0; font-size: 14px; color: var(--muted); max-width: 60ch; }
.hint strong { color: var(--danger-text); }

.btns { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 16px; }
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 44px; padding: 10px 16px;
  font: 600 15px/1 var(--f-body);
  color: var(--ink); background: var(--surface-2);
  border: 1.5px solid var(--ink); border-radius: 10px;
  cursor: pointer;
  transition: background-color .15s, transform .1s;
}
.btn:hover { background: #eadcc2; }
.btn:active { transform: translateY(1px); }
.btn.primary { background: var(--ink); color: var(--surface); }
.btn.primary:hover { background: #45301b; }
.btn.primary[data-active="true"] { background: var(--danger-text); border-color: var(--danger-text); }
.btn.ghost { background: transparent; }
.btn.ghost[aria-pressed="true"] { background: var(--run-bg); color: var(--accent-text); border-color: var(--accent-text); }
.btn .snd-on { display: none; }
.btn[aria-pressed="true"] .snd-on { display: inline; }
.btn[aria-pressed="true"] .snd-off { display: none; }
.btn.small { min-height: 34px; padding: 6px 12px; font-size: 13px; }

.plot { margin: 20px 0 0; }
.plot figcaption { display: flex; justify-content: space-between; font-size: 13px; color: var(--muted); margin-bottom: 6px; }
.plot figcaption span:first-child { font-weight: 600; color: var(--ink); }
.plot-box { position: relative; height: 110px; border: 1px solid var(--line); border-radius: 10px; background: var(--surface-2); overflow: hidden; }
#plot { display: block; width: 100%; height: 100%; }
.plot-thr { stroke: var(--danger-text); stroke-width: 1.5; stroke-dasharray: 5 4; }
.plot-line { fill: none; stroke: var(--accent); stroke-width: 2.2; stroke-linejoin: round; }
.plot-thr-lbl { position: absolute; right: 8px; font-size: 11px; font-weight: 700; color: var(--danger-text); transform: translateY(-120%); background: var(--surface-2); padding: 0 3px; }

/* ---------- serial ---------- */
.orig-note { margin: -6px 0 10px; font-size: 12.5px; color: var(--muted); }
.serial-tools { display: flex; align-items: center; gap: 10px; }
.baud { font-size: 12px; color: var(--muted); }
.serial-log {
  height: 250px; overflow-y: auto;
  background: #21170d; color: #eadcc3;
  border-radius: 10px; padding: 12px 14px;
  font-size: 13.5px; line-height: 1.6;
}
.serial-log .ln { white-space: pre-wrap; word-break: break-word; }
.serial-log .val { color: #c8b594; }
.serial-log .bad { color: #ff9f8f; font-weight: 500; margin-bottom: 6px; }
.serial-log .ok { color: #a9c4ff; margin-bottom: 6px; }
.serial-log .empty { color: #a8977a; font-style: italic; }
.serial-log:focus-visible { outline-offset: 3px; }

/* ---------- code ---------- */
.file { font-size: 12.5px; }
.code-legend { margin: -6px 0 10px; font-size: 12.5px; color: var(--muted); display: flex; flex-wrap: wrap; align-items: center; gap: 4px 8px; }
.code-legend .lg { display: inline-flex; align-items: center; gap: 8px; white-space: nowrap; }
.sw { display: inline-block; width: 12px; height: 12px; border-radius: 3px; vertical-align: -1px; }
.sw-run { background: var(--run-bg); box-shadow: inset 3px 0 var(--accent); }
.sw-lock { background: var(--lock-bg); box-shadow: inset 3px 0 var(--danger-text); margin-left: 6px; }
.sw-read { background: #f7e7b5; box-shadow: inset 3px 0 #b07d00; margin-left: 6px; }
.code-scroll { overflow-x: auto; border: 1px solid var(--line); border-radius: 10px; background: #fffaf1; }
#src { margin: 0; padding: 10px 0; font-size: 12.5px; line-height: 1.65; min-width: max-content; }
#src .l { display: block; padding: 0 14px 0 0; border-left: 3px solid transparent; transition: background-color .2s; }
#src .n { display: inline-block; width: 3.2em; padding-right: 1em; text-align: right; color: #7d6649; user-select: none; }
#src .l.run { background: var(--run-bg); border-left-color: var(--accent); }
#src .l.lock { background: var(--lock-bg); border-left-color: var(--danger-text); }
#src .l.cond { background: #efe5d2; border-left-color: var(--muted); }
#src .l.read { background: #f7e7b5; border-left-color: #b07d00; }
#src .anno { margin-left: 1.2em; padding: 1px 6px; border-radius: 4px; font-size: 11.5px; font-weight: 700; background: var(--ink); color: var(--surface); }
#src .anno.t { background: var(--danger-text); }
#src .anno.f { background: var(--accent-text); }
.tk-c { color: #6e5a41; font-style: italic; }
.tk-k { color: #1a47b3; font-weight: 500; }
.tk-s { color: #2f6b3a; }
.tk-n { color: #9a3412; }
.tk-f { color: #2b1d10; font-weight: 700; }

/* ---------- footer ---------- */
.foot { padding-block: 8px 48px; }
.foot-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 320px), 1fr)); gap: 16px 32px; border-top: 1px solid #d4bf99; padding-top: 24px; }
.foot h2 { font-size: 15px; margin-bottom: 6px; }
.foot p { margin: 0; font-size: 14.5px; color: var(--muted); max-width: 60ch; }
.foot .sig { margin-top: 24px; font-size: 13px; }

@media (max-width: 480px) {
  .card { padding: 14px; }
  .reading-val output { font-size: 34px; }
  .btns .btn { flex: 1 1 auto; }
  .btns .btn.primary { flex-basis: 100%; }
  .serial-log { height: 210px; font-size: 12.5px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
  .waves.on .wv { opacity: 1; }
  .puff { opacity: .6; }
}