:root {
  --bg: #0b1220;
  --panel: #121a2b;
  --text: #dbe7ff;
  --muted: #94a3b8;
  --border: #24314a;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: Inter, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: radial-gradient(circle at top, #111d35, #060b16);
}

.app { max-width: 1400px; margin: 0 auto; padding: 16px; }
.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 12px 16px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: rgba(10, 16, 30, 0.8);
}
.topbar h1 { margin: 0; font-size: 20px; }
.controls { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
button {
  border: 1px solid #2c3f65;
  background: #1a2b49;
  color: var(--text);
  border-radius: 8px;
  padding: 6px 10px;
  cursor: pointer;
}
button:hover { background: #22365b; }
.hint { color: var(--muted); font-size: 13px; }

main { display: grid; grid-template-columns: 220px 1fr; gap: 12px; margin-top: 12px; }
.legend {
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--panel);
  padding: 12px;
}
.legend-item {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 10px;
  font-size: 14px;
}
.legend-dot { width: 12px; height: 12px; border-radius: 50%; }

.viewport-wrap {
  position: relative;
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  background: #0d1729;
}
canvas {
  display: block;
  width: 100%;
  height: min(72vh, 760px);
}

.tooltip {
  position: absolute;
  max-width: 300px;
  padding: 8px 10px;
  background: rgba(6, 10, 20, 0.94);
  border: 1px solid #2d426b;
  border-radius: 8px;
  font-size: 13px;
  line-height: 1.45;
  pointer-events: none;
  z-index: 5;
}

.footer {
  margin-top: 10px;
  color: var(--muted);
  font-size: 12px;
}
code { color: #93c5fd; }