:root {
  --bg: #1e1e1e;
  --panel: #262626;
  --panel-border: #3a3a3a;
  --text: #e8e8e8;
  --text-dim: #9a9a9a;
  --accent: #3caaff;
  --danger: #ff3c3c;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, "Segoe UI", Roboto, sans-serif;
  font-size: 14px;
  overflow: hidden;
}

#app {
  display: flex;
  flex-direction: column;
  height: 100%;
}

header {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  background: var(--panel);
  border-bottom: 1px solid var(--panel-border);
  flex-wrap: wrap;
}

header h1 {
  font-size: 15px;
  font-weight: 600;
  margin: 0 12px 0 0;
  white-space: nowrap;
}

.spacer { flex: 1; }

button {
  background: #333;
  color: var(--text);
  border: 1px solid var(--panel-border);
  border-radius: 6px;
  padding: 6px 10px;
  font-size: 13px;
  cursor: pointer;
}
button:hover { background: #3d3d3d; }
button:active { background: #444; }
button.primary { background: var(--accent); border-color: var(--accent); color: #06121c; font-weight: 600; }
button.primary:hover { filter: brightness(1.08); }
button.danger { border-color: var(--danger); color: var(--danger); }
button:disabled { opacity: 0.45; cursor: default; }

#scaleIndicator {
  font-size: 12px;
  padding: 4px 8px;
  border-radius: 5px;
  background: #111;
  color: var(--text-dim);
  white-space: nowrap;
}
#scaleIndicator.calibrated { color: #7be08a; }

#main {
  flex: 1;
  display: flex;
  min-height: 0;
}

#sidebar {
  width: 190px;
  background: var(--panel);
  border-right: 1px solid var(--panel-border);
  padding: 10px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.tool-group h2 {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-dim);
  margin: 0 0 6px 0;
}

.tool-grid {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.tool-btn {
  text-align: left;
  background: transparent;
  border: 1px solid transparent;
}
.tool-btn.active {
  background: #1c3a52;
  border-color: var(--accent);
  color: #bfe2ff;
}

.palette {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 6px;
}
.swatch {
  width: 26px;
  height: 26px;
  border-radius: 5px;
  border: 2px solid #444;
  cursor: pointer;
  padding: 0;
}
.swatch.selected { border-color: #fff; box-shadow: 0 0 0 1px #fff; }

#canvasWrap {
  flex: 1;
  position: relative;
  background: #000;
  min-width: 0;
}

#canvas {
  width: 100%;
  height: 100%;
  display: block;
  cursor: crosshair;
}
#canvas.tool-select { cursor: default; }
#canvas.tool-pan { cursor: grab; }

#dropHint {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 10px;
  color: var(--text-dim);
  pointer-events: none;
}
#dropHint.hidden { display: none; }
#dropHint button { pointer-events: auto; }

footer {
  padding: 6px 12px;
  background: var(--panel);
  border-top: 1px solid var(--panel-border);
  font-size: 12px;
  color: var(--text-dim);
  min-height: 18px;
}

.file-input { display: none; }