/* SILT — dark-first, canvas-dominant UI. No frameworks, no remote assets. */
:root {
  --bg: #0b0d12;
  --panel: #12151c;
  --panel-2: #181c25;
  --border: #262b36;
  --text: #d7dbe3;
  --muted: #8a93a3;
  --accent: #5ec8ff;
  --accent-2: #ff8a5c;
  --danger: #ff5c6c;
  --ok: #6ee7a0;
  --focus: #ffd166;
  --radius: 6px;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, Ubuntu, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --left-w: 232px;
  --right-w: 300px;
  --top-h: 44px;
  --bottom-h: 26px;
}
* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; background: var(--bg); color: var(--text); font: 13px/1.4 var(--font); overscroll-behavior: none; }
button, input, select { font: inherit; color: inherit; }
:focus-visible { outline: 2px solid var(--focus); outline-offset: 1px; }
.muted { color: var(--muted); }
.small { font-size: 11px; }
[hidden] { display: none !important; }

.app {
  display: grid;
  grid-template-columns: var(--left-w) 1fr var(--right-w);
  grid-template-rows: var(--top-h) 1fr var(--bottom-h);
  grid-template-areas: "top top top" "left view right" "bottom bottom bottom";
  height: 100dvh;
  width: 100vw;
  overflow: hidden;
}
.app.left-collapsed { grid-template-columns: 0 1fr var(--right-w); }
.app.right-collapsed { grid-template-columns: var(--left-w) 1fr 0; }
.app.left-collapsed.right-collapsed { grid-template-columns: 0 1fr 0; }
.app.left-collapsed #leftpanel, .app.right-collapsed #rightpanel { display: none; }

/* ---------- top bar ---------- */
.topbar { grid-area: top; display: flex; align-items: center; gap: 10px; padding: 0 10px; background: var(--panel); border-bottom: 1px solid var(--border); overflow-x: auto; overflow-y: hidden; }
.brand { display: flex; align-items: center; gap: 6px; font-weight: 700; letter-spacing: 0.08em; }
.logo { color: var(--accent); font-size: 18px; }
.logo.big { font-size: 48px; }
.project { display: flex; align-items: center; gap: 4px; }
.save-name { background: transparent; border: 1px solid transparent; border-radius: var(--radius); padding: 3px 6px; width: 160px; }
.save-name:hover, .save-name:focus { border-color: var(--border); background: var(--panel-2); }
.modified-dot { color: var(--accent-2); font-size: 10px; }
.sim-controls, .view-modes, .topbar-actions { display: flex; align-items: center; gap: 4px; }
.topbar-actions { margin-left: auto; }
.speed { display: flex; border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; }
.speed .btn { border: 0; border-radius: 0; min-width: 30px; }

/* ---------- buttons ---------- */
.btn { background: var(--panel-2); border: 1px solid var(--border); border-radius: var(--radius); padding: 4px 9px; cursor: pointer; min-height: 28px; white-space: nowrap; }
.btn:hover { border-color: var(--muted); }
.btn.icon { padding: 4px 7px; min-width: 30px; }
.btn.small { min-height: 22px; padding: 1px 6px; font-size: 11px; }
.btn.primary { background: #1f4e6d; border-color: #2d6f99; }
.btn.danger { background: #5a1f2a; border-color: #8a2d3f; }
.btn.active, .btn.toggle[aria-pressed="true"], .speed-btn.active { background: #1f3a52; border-color: var(--accent); color: #fff; }
.btn:disabled { opacity: 0.4; cursor: default; }
select { background: var(--panel-2); border: 1px solid var(--border); border-radius: var(--radius); padding: 4px 6px; min-height: 28px; }
input[type="text"], input[type="search"], input[type="number"] { background: var(--panel-2); border: 1px solid var(--border); border-radius: var(--radius); padding: 4px 6px; min-height: 28px; }
input[type="range"] { width: 100%; accent-color: var(--accent); }

/* ---------- panels ---------- */
.panel { background: var(--panel); display: flex; flex-direction: column; min-height: 0; overflow: hidden; }
.panel.left { grid-area: left; border-right: 1px solid var(--border); }
.panel.right { grid-area: right; border-left: 1px solid var(--border); }
.panel-head { display: flex; align-items: center; gap: 6px; padding: 6px; border-bottom: 1px solid var(--border); }
.panel-head input[type="search"] { flex: 1; min-width: 0; }
.tools { display: grid; grid-template-columns: repeat(6, 1fr); gap: 3px; padding: 6px; border-bottom: 1px solid var(--border); }
.tool { background: var(--panel-2); border: 1px solid var(--border); border-radius: var(--radius); min-height: 30px; cursor: pointer; font-size: 14px; }
.tool.active { background: #1f3a52; border-color: var(--accent); }
.brush { padding: 6px 8px; border-bottom: 1px solid var(--border); }
.brush label { display: flex; justify-content: space-between; font-size: 11px; color: var(--muted); }
.categories { display: flex; flex-wrap: wrap; gap: 3px; padding: 6px; border-bottom: 1px solid var(--border); }
.categories button { background: transparent; border: 1px solid var(--border); border-radius: 12px; padding: 2px 8px; font-size: 11px; cursor: pointer; color: var(--muted); }
.categories button.active { color: #fff; border-color: var(--accent); background: #1f3a52; }
.palette { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 3px; padding: 6px; overflow-y: auto; overflow-x: hidden; flex: 1 1 0; min-height: 140px; align-content: start; }
.palette.walls { flex: 0 1 auto; min-height: 70px; max-height: 30%; border-top: 1px solid var(--border); }
.elem { display: flex; align-items: center; gap: 6px; min-width: 0; background: var(--panel-2); border: 1px solid var(--border); border-radius: var(--radius); padding: 4px 6px; cursor: pointer; text-align: left; min-height: 30px; font-size: 12px; }
.elem .swatch { width: 14px; height: 14px; border-radius: 3px; flex: 0 0 auto; border: 1px solid rgba(255,255,255,0.15); }
.elem .name { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.elem.active { border-color: var(--accent); background: #1f3a52; color: #fff; }

/* ---------- viewport ---------- */
.viewport { grid-area: view; position: relative; background: #05060a; min-width: 0; min-height: 0; overflow: hidden; }
#gl { display: block; width: 100%; height: 100%; touch-action: none; cursor: crosshair; image-rendering: pixelated; }
.hud { position: absolute; top: 8px; right: 8px; display: flex; gap: 4px; }
.diagnostics { position: absolute; top: 8px; left: 8px; margin: 0; padding: 6px 8px; background: rgba(11,13,18,0.85); border: 1px solid var(--border); border-radius: var(--radius); font: 11px/1.35 var(--mono); color: var(--text); pointer-events: none; max-width: 340px; }
.panel-expand { position: absolute; top: 50%; transform: translateY(-50%); z-index: 2; opacity: 0.8; }
.panel-expand.left { left: 4px; }
.panel-expand.right { right: 4px; }
.toasts { position: absolute; bottom: 10px; left: 50%; transform: translateX(-50%); display: flex; flex-direction: column; gap: 6px; pointer-events: none; }
.toast { background: rgba(24,28,37,0.95); border: 1px solid var(--border); border-left: 3px solid var(--accent); border-radius: var(--radius); padding: 6px 10px; max-width: 480px; pointer-events: auto; }
.toast.error { border-left-color: var(--danger); }
.toast.ok { border-left-color: var(--ok); }
.toast details { margin-top: 4px; }
.toast pre { margin: 4px 0 0; white-space: pre-wrap; font: 11px var(--mono); max-height: 120px; overflow: auto; }

/* ---------- right panel ---------- */
.tabs { display: flex; gap: 2px; flex: 1; }
.tab { background: transparent; border: 1px solid transparent; border-radius: var(--radius); padding: 4px 8px; cursor: pointer; color: var(--muted); }
.tab.active { color: #fff; background: var(--panel-2); border-color: var(--border); }
.tabpane { display: none; overflow-y: auto; padding: 8px; flex: 1; min-height: 0; }
.tabpane.active { display: block; }
.inspector h3 { margin: 6px 0 4px; font-size: 13px; }
.inspector h4 { margin: 8px 0 4px; font-size: 12px; color: var(--muted); text-transform: uppercase; letter-spacing: 0.05em; }
.kv { display: grid; grid-template-columns: 1fr auto; gap: 2px 8px; font-size: 12px; }
.kv dt { color: var(--muted); }
.kv dd { margin: 0; font-family: var(--mono); text-align: right; display: flex; gap: 4px; align-items: center; justify-content: flex-end; }
.kv input[type="number"] { width: 84px; min-height: 22px; padding: 1px 4px; font-family: var(--mono); font-size: 11px; text-align: right; }
.kv input[type="checkbox"] { accent-color: var(--accent); }
.pin { background: transparent; border: 0; cursor: pointer; padding: 0 2px; opacity: 0.6; }
.pin:hover, .pin.on { opacity: 1; }
.synlist { list-style: none; padding: 0; margin: 4px 0; font-size: 12px; }
.synlist li { display: grid; grid-template-columns: 1fr auto auto auto; gap: 4px; align-items: center; padding: 2px 0; border-bottom: 1px solid var(--border); }
.synlist input[type="number"] { width: 64px; min-height: 22px; padding: 1px 4px; font-size: 11px; }
.spikes { display: flex; gap: 1px; height: 12px; margin: 4px 0; }
.spikes span { flex: 1; background: var(--border); }
.spikes span.on { background: var(--accent); }
.scope { width: 100%; height: 200px; background: #06070b; border: 1px solid var(--border); border-radius: var(--radius); }
.scope-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 6px; }
.scope-legend { display: flex; flex-direction: column; gap: 2px; margin-top: 6px; font-size: 11px; font-family: var(--mono); }
.scope-legend div { display: flex; align-items: center; gap: 6px; }
.scope-legend i { width: 10px; height: 10px; border-radius: 2px; display: inline-block; }
.elem-info h3 { margin: 4px 0; }
.elem-info .tag { display: inline-block; background: var(--panel-2); border: 1px solid var(--border); border-radius: 10px; padding: 0 8px; font-size: 11px; margin: 2px 2px 6px 0; }
.elem-info .approx { color: var(--accent-2); }

/* ---------- status bar ---------- */
.statusbar { grid-area: bottom; display: flex; align-items: center; gap: 14px; padding: 0 10px; background: var(--panel); border-top: 1px solid var(--border); font: 11px var(--mono); color: var(--muted); overflow: hidden; white-space: nowrap; }
.status-item.grow { flex: 1; text-align: right; overflow: hidden; text-overflow: ellipsis; }

/* ---------- loading ---------- */
.loading { position: fixed; inset: 0; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 8px; background: var(--bg); z-index: 50; }
.app[aria-busy="false"] .loading { display: none; }

/* ---------- dialogs ---------- */
.dialog { background: var(--panel); color: var(--text); border: 1px solid var(--border); border-radius: 10px; padding: 0; max-width: min(92vw, 560px); width: 100%; box-shadow: 0 20px 60px rgba(0,0,0,0.6); }
.dialog.wide { max-width: min(96vw, 860px); }
.dialog::backdrop { background: rgba(0,0,0,0.55); }
.dialog-body { padding: 16px 18px; max-height: 86dvh; overflow-y: auto; }
.dialog h2 { margin: 0 0 10px; font-size: 16px; }
.dialog h3 { font-size: 13px; margin: 12px 0 6px; }
.row { display: flex; flex-wrap: wrap; gap: 6px; align-items: center; margin: 8px 0; }
.row.end { justify-content: flex-end; }
.saves-list, .examples-list { display: flex; flex-direction: column; gap: 4px; max-height: 40dvh; overflow-y: auto; }
.save-item, .example-item { display: grid; grid-template-columns: 1fr auto; gap: 6px; align-items: center; padding: 6px 8px; border: 1px solid var(--border); border-radius: var(--radius); background: var(--panel-2); }
.save-item .meta, .example-item .meta { font-size: 11px; color: var(--muted); }
.save-left { display: flex; gap: 8px; align-items: center; }
.save-item .actions { display: flex; gap: 3px; }
.recovery { border: 1px solid var(--accent-2); border-radius: var(--radius); padding: 8px; margin-top: 8px; }
.settings-grid { display: grid; grid-template-columns: 1fr auto; gap: 6px 10px; align-items: center; }
.help-cols { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.shortcuts td { padding: 2px 8px 2px 0; vertical-align: top; }
.shortcuts td:first-child { font-family: var(--mono); color: var(--accent); white-space: nowrap; }
.concepts dt { font-weight: 600; margin-top: 6px; }
.concepts dd { margin: 0 0 4px; color: var(--muted); }
.about { font: 11px/1.4 var(--mono); white-space: pre-wrap; }
.evolab { display: grid; gap: 8px; }
.evolab .grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 6px 12px; }
.evolab label { display: flex; flex-direction: column; gap: 2px; font-size: 12px; color: var(--muted); }
.evolab textarea { background: var(--panel-2); border: 1px solid var(--border); border-radius: var(--radius); color: var(--text); font: 12px var(--mono); padding: 4px 6px; min-height: 40px; }
.evolab table { border-collapse: collapse; width: 100%; font: 11px var(--mono); }
.evolab td, .evolab th { border-bottom: 1px solid var(--border); padding: 3px 4px; text-align: right; }
.evolab th:first-child, .evolab td:first-child { text-align: left; }
.evolab canvas { width: 100%; height: 120px; background: #06070b; border: 1px solid var(--border); border-radius: var(--radius); }
.evolab .status { font: 12px var(--mono); }

/* ---------- responsive ---------- */
@media (max-width: 900px) {
  :root { --left-w: 190px; --right-w: 240px; }
}
@media (max-width: 700px) {
  .app, .app.left-collapsed, .app.right-collapsed, .app.left-collapsed.right-collapsed { grid-template-columns: 1fr; grid-template-rows: var(--top-h) 1fr var(--bottom-h); grid-template-areas: "top" "view" "bottom"; }
  .topbar { gap: 6px; padding: 0 6px; }
  .panel { position: fixed; top: var(--top-h); bottom: var(--bottom-h); width: min(84vw, 300px); z-index: 20; box-shadow: 0 0 40px rgba(0,0,0,0.6); }
  .panel.left { left: 0; }
  .panel.right { right: 0; }
  .app.left-collapsed #leftpanel, .app.right-collapsed #rightpanel { display: none; }
  .help-cols { grid-template-columns: 1fr; }
  .save-name { width: 100px; }
  .brand-name { display: none; }
  .tool, .btn { min-height: 34px; }
}
@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; animation: none !important; }
}
@media (prefers-color-scheme: light) {
  body[data-theme="auto"] { --bg: #f2f3f6; --panel: #ffffff; --panel-2: #eef0f4; --border: #d3d7df; --text: #1b1f27; --muted: #5b6474; }
}