:root {
  color-scheme: dark;
  --bg: #16181d;
  --panel: #1e2128;
  --panel2: #252932;
  --border: #323743;
  --text: #dfe3ea;
  --muted: #8b93a3;
  --accent: #2ea3f2;
  --run: #22a447;
  --run-hover: #2bbb55;
  --stop: #d23c3c;
  --warn: #e0a526;
  --err: #ff5c5c;
  --ok: #46d36d;
  --danger: #ff8c8c;
  --canvas: #eef1f5;
  --dot: #cdd3dc;
  --topbar: #111318;
  --tabs: #181b21;
  --hover: #2f3440;
  --hover-border: #46506a;
  --input: #13151a;
  --code: #2a2f3a;
  --editor: #1a1c22;
  --problems: #1a1d24;
  --row-hover: #262a33;
  --wifi-bg: #173a24;
  --wifi-fg: #5fe08a;
  --add-bg: #1c3b57;
  --add-border: #2a5a85;
  --overlay: rgba(30, 33, 40, .97);
  --shadow: rgba(0, 0, 0, .35);
  --term-bg: #101215;
  --term-fg: #d8f5d0;
  --term-sys: #7fb8ff;
  --term-dim: #6b7380;
  --term-ts: #5f6a7a;
  --log-in: #9be39b;
  --log-out: #ffd27a;
  --chip: #23324a;
  --toast-bg: #2b313d;
  --toast-border: #3f4757;
  --help-key: #9fd0ff;
  --swatch-on: #fff;
  font-family: "Segoe UI", system-ui, -apple-system, Roboto, sans-serif;
}
/* light theme (⚙ Cài đặt / nút ☀ trên thanh công cụ); the circuit canvas is light in both themes */
:root[data-theme="light"] {
  color-scheme: light;
  --bg: #f3f5f8;
  --panel: #ffffff;
  --panel2: #f0f2f5;
  --border: #d5dae2;
  --text: #1f2430;
  --muted: #667085;
  --accent: #1a7fd4;
  --run: #1f9a42;
  --run-hover: #23b04b;
  --stop: #d23c3c;
  --warn: #b7791f;
  --err: #d92d2d;
  --ok: #1a8f3c;
  --danger: #d92d2d;
  --canvas: #f7f8fa;
  --dot: #d3d9e2;
  --topbar: #ffffff;
  --tabs: #f7f8fa;
  --hover: #e6e9ef;
  --hover-border: #b8c0cc;
  --input: #ffffff;
  --code: #eceff3;
  --editor: #ffffff;
  --problems: #f7f8fa;
  --row-hover: #eef1f5;
  --wifi-bg: #dff5e6;
  --wifi-fg: #1a7f3a;
  --add-bg: #e3f0fb;
  --add-border: #9cc6ea;
  --overlay: rgba(255, 255, 255, .97);
  --shadow: rgba(16, 24, 40, .16);
  --term-bg: #fbfcfd;
  --term-fg: #1d2a1d;
  --term-sys: #1d63c4;
  --term-dim: #8a93a0;
  --term-ts: #98a2b3;
  --log-in: #1a7f3a;
  --log-out: #a15c00;
  --chip: #dce8f7;
  --toast-bg: #ffffff;
  --toast-border: #d5dae2;
  --help-key: #1d63c4;
  --swatch-on: #1f2430;
}
* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; background: var(--bg); color: var(--text); overflow: hidden; font-size: 13px; }
button, select, input, textarea { font: inherit; color: inherit; }
button {
  background: var(--panel2); border: 1px solid var(--border); border-radius: 6px; padding: 4px 10px; cursor: pointer;
  transition: background .12s, border-color .12s;
}
button:hover:not(:disabled) { background: var(--hover); border-color: var(--hover-border); }
button:disabled { opacity: .45; cursor: default; }
button.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
select, input, textarea { background: var(--input); border: 1px solid var(--border); border-radius: 6px; padding: 4px 8px; outline: none; }
input:focus, select:focus, textarea:focus { border-color: var(--accent); }
code { background: var(--code); padding: 0 4px; border-radius: 3px; }

/* top bar */
.topbar { height: 46px; display: flex; align-items: center; gap: 12px; padding: 0 12px; background: var(--topbar); border-bottom: 1px solid var(--border); }
.brand { font-size: 15px; white-space: nowrap; }
.brand b { color: var(--accent); }
.logo { color: #ffd23f; }
:root[data-theme="light"] .logo { color: #e0a000; }
.project-name { width: 220px; background: transparent; border-color: transparent; font-weight: 600; }
.project-name:hover { border-color: var(--border); }
.top-actions { margin-left: auto; display: flex; gap: 6px; align-items: center; }
.top-actions select { max-width: 260px; }

/* layout */
.layout { display: flex; height: calc(100% - 46px); }
.pane { display: flex; flex-direction: column; min-width: 0; min-height: 0; }
.code-pane { width: 42%; min-width: 260px; background: var(--panel); }
.sim-pane { flex: 1; min-width: 300px; }
.gutter { background: var(--topbar); flex: none; position: relative; }
.gutter-v { width: 5px; cursor: col-resize; }
.gutter-h { height: 5px; cursor: row-resize; }
.gutter:hover { background: var(--accent); }
/* show/hide buttons in the middle of the splitters */
.gutter-btn { position: absolute; z-index: 5; left: 50%; top: 50%; padding: 0; display: flex; align-items: center; justify-content: center;
  font-size: 11px; line-height: 1; border-radius: 4px; color: var(--muted); background: var(--panel); border: 1px solid var(--border); cursor: pointer; }
.gutter-v .gutter-btn { width: 14px; height: 42px; transform: translate(-50%, -50%); }
.gutter-h .gutter-btn { width: 42px; height: 14px; transform: translate(-50%, -50%); }
.gutter-btn:hover:not(:disabled) { background: var(--accent); border-color: var(--accent); color: #fff; }
/* hidden code pane / collapsed bottom panel (only its tab bar stays): the splitter stays, holding the button */
.layout.code-hidden .code-pane { display: none; }
.layout.code-hidden .gutter-v, .sim-pane.bottom-collapsed .gutter-h { cursor: default; }
.layout.code-hidden .gutter-v .gutter-btn { left: 0; transform: translate(0, -50%); }
.bottom.collapsed { height: auto !important; min-height: 0; }
.bottom.collapsed .bottom-body, .bottom.collapsed .chk, .bottom.collapsed #btnClear { display: none; }

.tabs { display: flex; align-items: center; gap: 2px; padding: 0 6px; height: 34px; background: var(--tabs); border-bottom: 1px solid var(--border); flex: none; }
.tab { border: none; border-bottom: 2px solid transparent; border-radius: 0; background: transparent; padding: 6px 12px; color: var(--muted); }
.tab.active { color: var(--text); border-bottom-color: var(--accent); }
.tab:hover:not(.active) { background: transparent; color: var(--text); }
.tabs-spacer { flex: 1; }
.hint { color: var(--muted); font-size: 12px; padding-right: 6px; }
.badge { background: var(--accent); color: #fff; border-radius: 8px; padding: 0 6px; font-size: 11px; }
.chk { display: inline-flex; gap: 4px; align-items: center; color: var(--muted); font-size: 12px; margin-right: 6px; }

/* editor */
.editor-wrap { flex: 1; min-height: 0; position: relative; }
.editor-wrap .CodeMirror { position: absolute; inset: 0; height: auto; font-family: "JetBrains Mono", Consolas, "Courier New", monospace; font-size: 13.5px; line-height: 1.45; }
.cm-s-material-darker.CodeMirror { background: var(--editor); }
.cm-s-material-darker .CodeMirror-gutters { background: var(--editor); }
.cm-s-default.CodeMirror { background: var(--editor); color: var(--text); }
.cm-s-default .CodeMirror-gutters { background: var(--tabs); border-right-color: var(--border); }
.cm-s-default .CodeMirror-activeline-background { background: #eef3fb; }
.cm-error-line { background: rgba(255, 70, 70, .18) !important; }
.cm-warn-line { background: rgba(230, 170, 40, .12) !important; }
.cm-run-line { background: rgba(46, 163, 242, .10) !important; }

[hidden] { display: none !important; }
.problems { max-height: 34%; display: flex; flex-direction: column; border-top: 1px solid var(--border); background: var(--problems); }
.problems-head { display: flex; justify-content: space-between; align-items: center; padding: 4px 10px; color: var(--muted); font-size: 12px; }
.problems-head button { padding: 0 6px; border: none; background: none; }
.problems-list { overflow: auto; padding: 0 6px 6px; }
.problem { padding: 4px 8px; border-radius: 4px; cursor: pointer; font-family: Consolas, monospace; font-size: 12.5px; white-space: pre-wrap; }
.problem:hover { background: var(--row-hover); }
.problem.error { color: var(--err); }
.problem.warn { color: var(--warn); }
.problem .ln { color: var(--muted); margin-right: 8px; }

/* simulation */
.sim-toolbar { height: 42px; display: flex; align-items: center; gap: 6px; padding: 0 10px; background: var(--panel); border-bottom: 1px solid var(--border); flex: none; }
.sim-toolbar .run, .sim-toolbar .stop { width: 38px; height: 30px; border-radius: 50%; font-size: 14px; padding: 0; }
.sim-toolbar .run { background: var(--run); border-color: var(--run); color: #fff; }
.sim-toolbar .run:hover:not(:disabled) { background: var(--run-hover); }
.sim-toolbar .stop:not(:disabled) { background: var(--stop); border-color: var(--stop); color: #fff; }
.sim-time { font-family: Consolas, monospace; color: var(--muted); margin-left: 6px; min-width: 76px; }
.sim-status { color: var(--muted); font-size: 12px; }
.sim-status.running { color: var(--ok); }
.sim-status.error { color: var(--err); }
.wifi-badge { background: var(--wifi-bg); color: var(--wifi-fg); border-radius: 10px; padding: 1px 8px; font-size: 12px; }
.add-part { background: var(--add-bg); border-color: var(--add-border); }

.sim-area { position: relative; flex: 1; min-height: 120px; overflow: hidden; }
.canvas {
  position: absolute; inset: 0; overflow: hidden; background-color: var(--canvas); cursor: grab;
  background-image: radial-gradient(var(--dot) 1px, transparent 1px);
  user-select: none; touch-action: none;
}
.canvas:active { cursor: grabbing; }
.canvas-hint { position: absolute; left: 10px; bottom: 6px; font-size: 11px; color: #7c8594; pointer-events: none; }
.world { position: absolute; left: 0; top: 0; transform-origin: 0 0; }
.parts-layer, .pins-layer { position: absolute; left: 0; top: 0; }
.wires-layer { position: absolute; left: 0; top: 0; width: 1px; height: 1px; overflow: visible; pointer-events: none; }
.part { position: absolute; transform-origin: 50% 50%; cursor: move; }
.part svg { display: block; overflow: visible; }
.part.interactive { cursor: pointer; }
.part.selected { outline: 1.5px dashed var(--accent); outline-offset: 4px; }
.pl { font-size: 5.6px; fill: #e8e8e8; font-family: Consolas, monospace; }
.pin { position: absolute; width: 8px; height: 8px; margin: -4px 0 0 -4px; border-radius: 50%; cursor: crosshair; }
.pin:hover { background: rgba(46, 163, 242, .55); box-shadow: 0 0 0 2px rgba(46, 163, 242, .35); }
.wire { pointer-events: none; }
.wire-hit { stroke: transparent; stroke-width: 10; fill: none; pointer-events: stroke; cursor: pointer; }
.wire-outline { stroke: rgba(0, 0, 0, .35); stroke-width: 4.2; fill: none; stroke-linejoin: round; stroke-linecap: round; }
.wire-line { stroke-width: 2.6; fill: none; stroke-linejoin: round; stroke-linecap: round; }
.wire.selected .wire-outline { stroke: var(--accent); stroke-width: 6; }
.wire .wp { fill: #fff; stroke: var(--accent); stroke-width: 1.5; pointer-events: all; cursor: move; }
.wire-temp { stroke: var(--accent); stroke-width: 2; stroke-dasharray: 5 4; fill: none; }
.pin-tip { position: absolute; display: none; background: #111a; backdrop-filter: blur(2px); color: #fff; padding: 2px 7px; border-radius: 4px; font: 12px Consolas, monospace; pointer-events: none; z-index: 5; background: rgba(17, 19, 24, .85); }

.inspector {
  position: absolute; right: 10px; top: 10px; width: 250px; max-height: calc(100% - 20px); overflow: auto;
  background: var(--overlay); border: 1px solid var(--border); border-radius: 10px; padding: 10px 12px; box-shadow: 0 6px 24px var(--shadow); z-index: 4;
}
.inspector h4 { margin: 0 0 2px; font-size: 13px; }
.inspector .sub { color: var(--muted); font-size: 11.5px; margin-bottom: 8px; font-family: Consolas, monospace; }
.inspector .field { display: flex; flex-direction: column; gap: 3px; margin: 8px 0; font-size: 12px; color: var(--muted); }
.inspector .field input, .inspector .field select { width: 100%; }
.inspector .field .val { color: var(--text); font-family: Consolas, monospace; }
.inspector .row { display: flex; gap: 6px; margin-top: 10px; }
.inspector .row button { flex: 1; }
.inspector .danger { color: var(--danger); }
.swatches { display: flex; flex-wrap: wrap; gap: 5px; }
.swatch { width: 20px; height: 20px; border-radius: 50%; border: 2px solid transparent; cursor: pointer; padding: 0; }
.swatch.active { border-color: var(--swatch-on); }
input[type=range] { padding: 0; accent-color: var(--accent); }

/* bottom panel */
.bottom { height: 32%; min-height: 80px; display: flex; flex-direction: column; background: var(--panel); flex: none; }
.bottom-body { flex: 1; min-height: 0; position: relative; }
.panel { position: absolute; inset: 0; display: none; flex-direction: column; }
.panel.active { display: flex; }
.serial-out { flex: 1; margin: 0; padding: 6px 10px; overflow: auto; font: 12.5px/1.4 Consolas, "Courier New", monospace; white-space: pre-wrap; word-break: break-all; color: var(--term-fg); background: var(--term-bg); }
.serial-out .sys { color: var(--term-sys); }
.serial-out .warn { color: var(--warn); }
.serial-out .err { color: var(--err); }
.serial-out .boot { color: var(--term-dim); }
.serial-out .ts { color: var(--term-ts); }
.serial-in { display: flex; gap: 6px; padding: 6px; border-top: 1px solid var(--border); }
.serial-in input { flex: 1; font-family: Consolas, monospace; }

.mqtt { display: flex; flex-direction: column; gap: 6px; padding: 8px; height: 100%; }
.mqtt-row { display: flex; gap: 6px; align-items: center; flex-wrap: wrap; }
.mqtt-row input { flex: 1; min-width: 120px; }
.mqtt-row input[type=checkbox] { flex: none; min-width: 0; }
#mqttUrl { flex: 2; }
.mqtt-state { font-size: 12px; color: var(--muted); }
.mqtt-state.on { color: var(--ok); }
.mqtt-subs { display: flex; gap: 4px; flex-wrap: wrap; }
.mqtt-subs .chip { background: var(--chip); border-radius: 10px; padding: 1px 8px; font-size: 11.5px; cursor: pointer; }
.mqtt-log, .net-log { flex: 1; overflow: auto; background: var(--term-bg); color: var(--term-fg); border-radius: 6px; padding: 6px 8px; font: 12px/1.45 Consolas, monospace; }
.net-log { height: 100%; border-radius: 0; }
.log-line { white-space: pre-wrap; word-break: break-all; }
.log-line .t { color: var(--term-ts); margin-right: 6px; }
.log-line .k { display: inline-block; min-width: 58px; color: var(--term-sys); }
.log-line.err { color: var(--err); }
.log-line.in { color: var(--log-in); }
.log-line.out { color: var(--log-out); }

/* modals */
.modal { position: fixed; inset: 0; background: rgba(0, 0, 0, .5); display: flex; align-items: center; justify-content: center; z-index: 50; }
.modal[hidden] { display: none; }
.modal-box { background: var(--panel); border: 1px solid var(--border); border-radius: 12px; width: min(520px, 94vw); max-height: 88vh; display: flex; flex-direction: column; box-shadow: 0 20px 60px var(--shadow); }
.modal-box.wide { width: min(860px, 96vw); }
.modal-head { display: flex; align-items: center; gap: 10px; padding: 10px 14px; border-bottom: 1px solid var(--border); }
.modal-head input { flex: 1; }
.modal-head .modal-close { margin-left: auto; border: none; background: none; font-size: 16px; }
.modal-body { padding: 12px 16px; overflow: auto; }
.modal-actions { display: flex; justify-content: flex-end; margin-top: 10px; }
.field { display: flex; flex-direction: column; gap: 4px; margin-bottom: 12px; }
.field small { color: var(--muted); }
.field textarea { font-family: Consolas, monospace; font-size: 12px; }
.part-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); gap: 10px; padding: 14px; overflow: auto; }
.part-cat { grid-column: 1 / -1; color: var(--muted); font-size: 12px; text-transform: uppercase; letter-spacing: .05em; margin-top: 4px; }
.part-card { background: var(--canvas); border-radius: 10px; padding: 8px; cursor: pointer; display: flex; flex-direction: column; align-items: center; gap: 6px; border: 2px solid transparent; }
:root[data-theme="light"] .part-card { border-color: var(--border); }
.part-card:hover { border-color: var(--accent); }
.part-card .thumb { height: 86px; width: 100%; display: flex; align-items: center; justify-content: center; }
.part-card .thumb svg { max-width: 100%; max-height: 86px; }
.part-card span { color: #222; font-size: 12px; text-align: center; }
.help h3 { margin: 14px 0 6px; color: var(--accent); font-size: 14px; }
.help ul { margin: 4px 0; padding-left: 20px; }
.help li { margin: 3px 0; line-height: 1.45; }
.help table { border-collapse: collapse; width: 100%; font-size: 12.5px; }
.help td { border-top: 1px solid var(--border); padding: 4px 6px; vertical-align: top; }
.help td:first-child { white-space: nowrap; color: var(--help-key); }

.toast { position: fixed; left: 50%; bottom: 28px; transform: translateX(-50%); background: var(--toast-bg); border: 1px solid var(--toast-border); padding: 8px 16px; border-radius: 8px; z-index: 60; box-shadow: 0 6px 20px var(--shadow); }

@media (max-width: 820px) {
  .layout { flex-direction: column; }
  .code-pane { width: 100% !important; height: 40%; }
  .gutter-v { width: auto; height: 5px; cursor: default; }
  .gutter-v .gutter-btn { transform: translate(-50%, -50%) rotate(90deg); }
  .brand, .project-name { display: none; }
  .top-actions { margin-left: 0; overflow-x: auto; }
}