*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { font-size: 16px; -webkit-font-smoothing: antialiased; }
body {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: system-ui, -apple-system, sans-serif;
  background: #060a10;
  color: #fafafa;
  overflow: hidden;
}

svg {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  cursor: pointer;
}

.connection {
  stroke-linecap: round;
  transition: stroke-opacity 0.3s ease;
}

.node-circle {
  cursor: pointer;
  transition: r 0.15s ease;
}

.node-label {
  font-size: 9px;
  font-family: system-ui, -apple-system, sans-serif;
  fill: rgba(255,255,255,0.35);
  text-anchor: middle;
  pointer-events: none;
  letter-spacing: 0.04em;
}

.layer-label {
  font-size: 11px;
  font-family: system-ui, -apple-system, sans-serif;
  fill: rgba(255,255,255,0.2);
  text-anchor: middle;
  pointer-events: none;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

#hint {
  position: fixed;
  bottom: 22px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 12px;
  color: rgba(255, 255, 255, 0.25);
  letter-spacing: 0.06em;
  pointer-events: none;
  white-space: nowrap;
  z-index: 10;
}