:root {
  --bg: #f3f4f6; --panel: #ffffff; --ink: #1f2937; --muted: #6b7280; --line: #d1d5db; --accent: #2563eb;
  --canvas: #fbfbfa; --dot: #d6d8dc; --body: #ffffff; --body-chip: #eef4ff; --stroke: #374151;
  --wire: #4b5563; --v1: #16a34a; --v0: #14532d; --vz: #94a3b8; --vx: #dc2626; --sel: #2563eb;
  --led-off: #3f1d1d; --led-on: #ef4444; --warn: #b45309; --err: #b91c1c; --ok: #15803d;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #111318; --panel: #1a1d23; --ink: #e5e7eb; --muted: #9ca3af; --line: #374151; --accent: #60a5fa;
    --canvas: #15171c; --dot: #2a2e36; --body: #1f232b; --body-chip: #1d2738; --stroke: #cbd5e1;
    --wire: #9ca3af; --v1: #4ade80; --v0: #166534; --vz: #64748b; --vx: #f87171; --sel: #60a5fa;
    --led-off: #3b1515; --led-on: #f87171; --warn: #fbbf24; --err: #f87171; --ok: #4ade80;
  }
}
* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
body {
  font: 13px/1.4 system-ui, sans-serif; background: var(--bg); color: var(--ink);
  display: grid; grid-template-columns: 220px 1fr 290px; grid-template-rows: auto 1fr 210px; height: 100vh; overflow: hidden;
}
button, input, select { font: inherit; color: var(--ink); background: var(--panel); border: 1px solid var(--line); border-radius: 4px; padding: 3px 8px; }
button { cursor: pointer; }
button:hover:not(:disabled) { border-color: var(--accent); }
button:disabled { opacity: .45; cursor: default; }
button.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
button.on { outline: 2px solid var(--accent); }
.muted { color: var(--muted); }
.mono { font-family: ui-monospace, Consolas, monospace; }
.spacer { flex: 1; }

#top { grid-column: 1 / -1; display: flex; align-items: center; gap: 6px; padding: 6px 10px; background: var(--panel); border-bottom: 1px solid var(--line); flex-wrap: wrap; }
.brand { margin-right: 4px; }
#tabs { display: flex; gap: 2px; margin-left: 12px; flex-wrap: wrap; }
#tabs button { border-radius: 4px 4px 0 0; }
#tabs a.tab { display: inline-block; padding: 3px 8px; margin-left: 8px; border: 1px solid var(--line); border-radius: 4px 4px 0 0; color: var(--ink); text-decoration: none; background: var(--panel); }
#tabs a.tab:hover { border-color: var(--accent); }
a.tab-link { display: inline-block; padding: 3px 8px; border: 1px solid var(--line); border-radius: 4px; color: var(--ink); text-decoration: none; background: var(--panel); }
a.tab-link:hover { border-color: var(--accent); }
#tabs button.active { background: var(--bg); border-bottom-color: var(--bg); font-weight: 600; }

aside { background: var(--panel); overflow: auto; padding: 8px 10px; }
#palette { border-right: 1px solid var(--line); }
#inspector { border-left: 1px solid var(--line); }
aside h3 { font-size: 11px; text-transform: uppercase; letter-spacing: .05em; color: var(--muted); margin: 12px 0 4px; }
aside h3:first-child { margin-top: 0; }
.pal-item { display: flex; justify-content: space-between; gap: 6px; width: 100%; text-align: left; margin: 2px 0; padding: 3px 6px; }
.pal-item small { color: var(--muted); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.pal-item.active { border-color: var(--accent); background: color-mix(in srgb, var(--accent) 12%, var(--panel)); }
#pal-search { width: 100%; margin-bottom: 4px; }
.chip-row { display: flex; gap: 4px; align-items: center; margin: 2px 0; }
.chip-row .pal-item { flex: 1; margin: 0; }
.row { display: flex; flex-direction: column; gap: 2px; margin-bottom: 8px; }
.row > label { color: var(--muted); font-size: 12px; }
.row input, .row select { width: 100%; }
.inline { display: flex; gap: 4px; flex-wrap: wrap; align-items: center; }
table.kv { width: 100%; border-collapse: collapse; font-size: 12px; }
table.kv td, table.kv th { border-bottom: 1px solid var(--line); padding: 2px 4px; text-align: left; vertical-align: top; }
.note { font-size: 12px; color: var(--muted); }
.err { color: var(--err); }
.ok { color: var(--ok); }

#stage { position: relative; overflow: hidden; background: var(--canvas); }
#canvas {
  position: absolute; inset: 0; width: 100%; height: 100%; touch-action: none; user-select: none;
  background-image: radial-gradient(var(--dot) 1.2px, transparent 1.2px);
}
#toolbar { position: absolute; top: 8px; left: 8px; z-index: 2; display: flex; gap: 4px; background: var(--panel); padding: 4px; border: 1px solid var(--line); border-radius: 6px; }
#banner { position: absolute; bottom: 28px; left: 50%; transform: translateX(-50%); z-index: 2; background: var(--accent); color: #fff; padding: 4px 12px; border-radius: 6px; pointer-events: none; }
#status { position: absolute; left: 8px; bottom: 6px; z-index: 2; color: var(--muted); font: 12px ui-monospace, Consolas, monospace; pointer-events: none; }

/* Schematic */
.comp .body { fill: var(--body); stroke: var(--stroke); stroke-width: 1.4; }
.comp.chip .body { fill: var(--body-chip); }
.comp.missing .body { fill: none; stroke: var(--err); stroke-dasharray: 4 3; }
.comp text { fill: var(--ink); font: 10px ui-monospace, Consolas, monospace; }
.comp .title { font: 600 11px system-ui, sans-serif; }
.comp .ref { fill: var(--muted); font: 10px system-ui, sans-serif; }
.comp .pnum { fill: var(--muted); font-size: 8px; }
.comp .stub { stroke: var(--stroke); stroke-width: 1.4; }
.comp.sel .body, .comp.sel .flag { stroke: var(--sel); stroke-width: 2.5; }
.comp.ghost { opacity: .5; pointer-events: none; }
.comp .flag { fill: var(--body); stroke: var(--stroke); stroke-width: 1.2; }
.comp.port .flag { fill: var(--body-chip); }
.comp .power { stroke: var(--stroke); stroke-width: 1.6; fill: none; }
.comp .led-body { fill: var(--led-off); stroke: var(--stroke); }
.comp .led-body.v1 { fill: var(--led-on); filter: drop-shadow(0 0 6px var(--led-on)); }
.comp .led-body.vx { fill: none; stroke: var(--vx); stroke-dasharray: 3 2; }
.comp .track { fill: var(--v0); stroke: var(--stroke); }
.comp .on .track { fill: var(--v1); }
.comp .knob { fill: #fff; stroke: var(--stroke); }
.comp.switch, .comp.button { cursor: pointer; }
.comp .resistor { fill: none; stroke: var(--stroke); stroke-width: 1.4; }

.wire .line { fill: none; stroke: var(--wire); stroke-width: 2; stroke-linejoin: round; }
.wire .hit { fill: none; stroke: transparent; stroke-width: 10; cursor: pointer; }
.wire.sel .line { stroke: var(--sel); stroke-width: 3; }
.wire.v1 .line { stroke: var(--v1); stroke-width: 2.6; }
.wire.v0 .line { stroke: var(--v0); }
.wire.vz .line { stroke: var(--vz); stroke-dasharray: 5 4; }
.wire.vx .line { stroke: var(--vx); stroke-width: 2.6; }
.junction { fill: var(--wire); }
.pin { fill: var(--canvas); stroke: var(--stroke); stroke-width: 1; cursor: crosshair; }
.pin.connected { fill: var(--stroke); r: 2.2; }
.pin:hover { r: 5; stroke: var(--accent); }
.draft { fill: none; stroke: var(--accent); stroke-width: 2; stroke-dasharray: 6 4; pointer-events: none; }

/* Run panel */
#runpanel { grid-column: 1 / -1; background: var(--panel); border-top: 1px solid var(--line); display: flex; flex-direction: column; min-height: 0; }
#runbar { display: flex; gap: 8px; align-items: center; padding: 6px 10px; border-bottom: 1px solid var(--line); flex-wrap: wrap; }
#runbody { display: grid; grid-template-columns: minmax(260px, 38%) 1fr; flex: 1; min-height: 0; }
#messages { margin: 0; padding: 6px 10px; list-style: none; overflow: auto; border-right: 1px solid var(--line); font-size: 12px; }
#messages li { padding: 2px 0; border-bottom: 1px dashed var(--line); cursor: default; }
#messages li[data-ref] { cursor: pointer; }
#messages .k { font-weight: 600; margin-right: 4px; }
#messages .k.warn { color: var(--warn); }
#messages .k.err { color: var(--err); }
#messages .k.ok { color: var(--ok); }
#scope-wrap { position: relative; overflow: auto; }
#scope { display: block; width: 100%; }
#scope-empty { position: absolute; top: 6px; left: 10px; margin: 0; }

#toast { position: fixed; left: 50%; bottom: 230px; transform: translateX(-50%); background: var(--ink); color: var(--bg); padding: 6px 14px; border-radius: 6px; opacity: 0; transition: opacity .2s; pointer-events: none; z-index: 10; max-width: 70vw; }
#toast.show { opacity: .95; }
#toast.error { background: var(--err); color: #fff; }

dialog { max-width: 620px; border: 1px solid var(--line); border-radius: 8px; background: var(--panel); color: var(--ink); }
dialog h2 { margin-top: 0; font-size: 17px; }
dialog h3 { font-size: 14px; margin-bottom: 4px; }
dialog ol { padding-left: 20px; margin-top: 4px; }
dialog::backdrop { background: rgb(0 0 0 / .4); }

/* Devices panel: floats over the right side of the drawing. */
#devpanel { position: absolute; top: 8px; right: 8px; bottom: 8px; width: min(680px, 70%); z-index: 3; overflow: auto;
  background: var(--panel); border: 1px solid var(--line); border-radius: 8px; padding: 8px 10px; box-shadow: 0 6px 24px rgb(0 0 0 / .35); }
#devpanel header { display: flex; align-items: center; gap: 6px; margin-bottom: 4px; }
#devpanel h3 { font-size: 11px; text-transform: uppercase; letter-spacing: .05em; color: var(--muted); margin: 10px 0 4px; }
#devpanel textarea { width: 100%; font: 12px ui-monospace, Consolas, monospace; margin: 4px 0; background: var(--bg); color: var(--ink); border: 1px solid var(--line); border-radius: 4px; }
#devpanel pre { max-height: 120px; overflow: auto; background: #0b0f0c; color: #9be29b; padding: 6px; border-radius: 4px; font-size: 12px; margin: 2px 0; white-space: pre-wrap; }
.filebtn { display: inline-block; border: 1px solid var(--line); border-radius: 4px; padding: 3px 8px; cursor: pointer; }
.filebtn:hover { border-color: var(--accent); }
.crt-bezel { background: #1b1b1b; border-radius: 22px; padding: 18px; box-shadow: inset 0 0 0 3px #2c2c2c, 0 2px 6px rgb(0 0 0 / .5); position: relative; }
.crt-bezel canvas { display: block; width: 100%; aspect-ratio: 640 / 400; border-radius: 14px / 18px; image-rendering: pixelated; background: #000; }
.crt-bezel::after { content: ''; position: absolute; inset: 18px; border-radius: 14px / 18px; pointer-events: none;
  background: repeating-linear-gradient(to bottom, rgb(0 0 0 / .22) 0 1px, transparent 1px 3px); box-shadow: inset 0 0 40px rgb(0 0 0 / .6); }
.crt-green canvas { filter: drop-shadow(0 0 3px rgb(51 255 102 / .45)); }
.crt-amber canvas { filter: drop-shadow(0 0 3px rgb(255 176 0 / .45)); }
.dev-disk { border: 1px solid var(--line); border-radius: 6px; padding: 6px; margin: 4px 0; }
.dled { display: inline-block; width: 9px; height: 9px; border-radius: 50%; background: #3a1a12; margin-right: 6px; vertical-align: middle; }
.dled.on { background: #ff5a2a; box-shadow: 0 0 6px #ff5a2a; }
.req { background: color-mix(in srgb, var(--accent) 15%, var(--panel)); border: 1px solid var(--accent); padding: 4px 6px; border-radius: 4px; margin: 4px 0; }
.crt-bezel canvas:focus { outline: 2px solid var(--accent); outline-offset: 2px; }