:root {
  --bg: #0b0b12;
  --panel: #171722;
  --panel-border: #2a2a3a;
  --text: #e5e7eb;
  --text-dim: #9296a6;
  --accent: #facc15;
  --danger: #ef4444;
  --radius: 8px;
}

* { box-sizing: border-box; }

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

body {
  display: flex;
  flex-direction: column;
  height: 100vh;
}

.topbar {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 10px 16px;
  background: var(--panel);
  border-bottom: 1px solid var(--panel-border);
  flex-wrap: wrap;
}

.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 18px;
  letter-spacing: 0.3px;
}

.brand-mark {
  color: var(--accent);
  font-size: 20px;
}

.toolbar {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.divider {
  width: 1px;
  height: 24px;
  background: var(--panel-border);
  margin: 0 4px;
}

.btn {
  background: #232333;
  color: var(--text);
  border: 1px solid var(--panel-border);
  border-radius: var(--radius);
  padding: 7px 12px;
  font-size: 13px;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s;
  white-space: nowrap;
}

.btn:hover { background: #2c2c40; border-color: #3d3d54; }
.btn:active { transform: translateY(1px); }

.btn.primary {
  background: var(--accent);
  color: #1a1a1a;
  border-color: var(--accent);
  font-weight: 600;
}
.btn.primary:hover { background: #fde047; }

.btn.danger { color: #fca5a5; }
.btn.danger:hover { background: #3a1f1f; border-color: var(--danger); }

.btn.icon { width: 32px; text-align: center; padding: 7px 0; font-weight: 700; }

.file-btn { display: inline-flex; align-items: center; }

.zoom-label { font-size: 12px; color: var(--text-dim); width: 42px; text-align: center; }

.swatches {
  display: flex;
  align-items: center;
  gap: 6px;
}

.swatch {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  border: 2px solid rgba(255,255,255,0.15);
  background: var(--sw, #64748b);
  cursor: pointer;
  padding: 0;
}
.swatch:hover { border-color: #fff; }

.swatch.custom {
  position: relative;
  overflow: hidden;
  background: conic-gradient(red, yellow, lime, cyan, blue, magenta, red);
}
.swatch.custom input {
  position: absolute;
  inset: 0;
  opacity: 0;
  cursor: pointer;
  border: none;
  padding: 0;
}

.canvas-wrap {
  flex: 1;
  overflow: auto;
  background: var(--bg);
  position: relative;
}

#canvas {
  display: block;
  background-image:
    linear-gradient(rgba(255,255,255,0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.035) 1px, transparent 1px);
  background-size: 40px 40px;
}

.block-rect {
  cursor: grab;
  stroke: #05050a;
  stroke-width: 1.5;
}

.block.selected .block-rect {
  stroke: var(--accent);
  stroke-width: 3;
}

.block-label {
  fill: #0b0b12;
  font-size: 15px;
  font-weight: 600;
  pointer-events: none;
  user-select: none;
  dominant-baseline: middle;
  text-anchor: middle;
}

.block-sublabel {
  fill: rgba(0,0,0,0.55);
  font-size: 11px;
  pointer-events: none;
  user-select: none;
  dominant-baseline: middle;
  text-anchor: middle;
}

.port {
  fill: #0b0b12;
  stroke: #cbd5e1;
  stroke-width: 1.5;
  cursor: crosshair;
  opacity: 0;
  transition: opacity 0.1s;
}

.block:hover .port,
.block.selected .port {
  opacity: 1;
}

.port:hover {
  fill: var(--accent);
  stroke: var(--accent);
  r: 7;
}

.connection-path {
  fill: none;
  stroke: #cbd5e1;
  stroke-width: 2.5;
  cursor: pointer;
  marker-end: url(#arrowhead);
}

.connection-hit {
  fill: none;
  stroke: transparent;
  stroke-width: 16;
  cursor: pointer;
}

.connection.selected .connection-path {
  stroke: var(--accent);
  marker-end: url(#arrowhead-selected);
}

.block-edit-input {
  position: absolute;
  z-index: 50;
  font-size: 15px;
  font-weight: 600;
  text-align: center;
  border: 2px solid var(--accent);
  border-radius: 4px;
  background: #fff;
  color: #0b0b12;
  padding: 2px 4px;
}

.statusbar {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 6px 14px;
  background: var(--panel);
  border-top: 1px solid var(--panel-border);
  font-size: 12px;
  color: var(--text-dim);
}

#autosaveText {
  white-space: nowrap;
  opacity: 0.8;
}