:root {
  --bg: #0f1115;
  --panel: #1a1d24;
  --line: #2a2f3a;
  --ink: #e6e9ef;
  --muted: #9aa3b2;
  --accent: #4cc2ff;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  padding: 1.5rem;
  font: 16px/1.4 system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  background: var(--bg);
  color: var(--ink);
}

.masthead { text-align: center; }
.masthead h1 { margin: 0; font-size: 1.6rem; letter-spacing: 0.02em; }
.tagline { margin: 0.25rem 0 0; color: var(--muted); font-size: 0.9rem; }

.lab {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 960px;
  width: 100%;
  margin: 0 auto;
}

.canvas-wrap {
  flex: 1;
  min-height: 320px;
  display: flex;
  background: #000;
  border: 1px solid var(--line);
  border-radius: 8px;
  overflow: hidden;
}

#canvas {
  width: 100%;
  height: 100%;
  display: block;
}

.toolbar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  padding: 0.75rem 1rem;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.group {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

button {
  font: inherit;
  color: var(--ink);
  background: #232732;
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 0.45rem 0.9rem;
  cursor: pointer;
}

button:hover { border-color: var(--accent); }

label[for="speed"] { color: var(--muted); font-size: 0.9rem; }
#speed { accent-color: var(--accent); }

.counter { margin-left: auto; }
.counter-label { color: var(--muted); font-size: 0.9rem; }
#generation {
  font-variant-numeric: tabular-nums;
  font-weight: 600;
  color: var(--accent);
  min-width: 3ch;
  text-align: right;
}

@media (max-width: 600px) {
  .counter { margin-left: 0; }
}