:root {
  --bg: #0e1116;
  --panel: #171b22;
  --accent: #4fd1c5;
  --text: #e2e8f0;
  --muted: #7d8896;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family:
    system-ui,
    -apple-system,
    Segoe UI,
    Roboto,
    sans-serif;
}

header {
  padding: 16px 24px;
  border-bottom: 1px solid #232a33;
}

header h1 {
  margin: 0;
  font-size: 20px;
  color: var(--accent);
}

.subtitle {
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 13px;
}

main {
  display: flex;
  gap: 20px;
  padding: 20px;
  align-items: flex-start;
  flex-wrap: wrap;
}

#canvas-wrap {
  position: relative;
}

canvas {
  background: #0a0d12;
  border: 1px solid #232a33;
  border-radius: 8px;
  display: block;
}

#hud {
  position: absolute;
  top: 8px;
  left: 8px;
  font-size: 12px;
  color: var(--muted);
  background: rgba(10, 13, 18, 0.7);
  padding: 6px 10px;
  border-radius: 6px;
  line-height: 1.5;
  pointer-events: none;
  white-space: pre;
}

#controls {
  background: var(--panel);
  padding: 16px;
  border-radius: 8px;
  width: 300px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.ctrl {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.ctrl label {
  font-size: 13px;
  color: var(--muted);
}

input[type='range'] {
  width: 100%;
  accent-color: var(--accent);
}

select {
  background: #0e1116;
  color: var(--text);
  border: 1px solid #2a323d;
  border-radius: 6px;
  padding: 6px;
}

.buttons {
  flex-direction: row;
  gap: 8px;
}

button {
  flex: 1;
  background: #222a34;
  color: var(--text);
  border: 1px solid #2f3945;
  border-radius: 6px;
  padding: 8px;
  cursor: pointer;
  font-size: 13px;
}

button:hover {
  background: #2c3542;
}

button#run {
  background: var(--accent);
  color: #05201d;
  border: none;
}

.checkboxes {
  flex-direction: row;
  gap: 12px;
  flex-wrap: wrap;
}

.checkboxes label {
  display: flex;
  align-items: center;
  gap: 4px;
  color: var(--text);
}