*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg: #111;
  --surface: #1a1a1a;
  --accent: #00e000;
  --text: #e0e0e0;
  --muted: #888;
  --border: #333;
  --radius: 6px;
  --font: 'Courier New', Courier, monospace;
}

html, body {
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  overflow: hidden;
}

#app {
  display: flex;
  flex-direction: column;
  height: 100vh;
  max-width: 600px;
  margin: 0 auto;
  padding: 8px;
  gap: 8px;
}

/* ── Header ──────────────────────────────────────────────── */

#header {
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  gap: 6px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 10px 14px;
}

#title-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

#game-title {
  font-size: 1.4rem;
  color: var(--accent);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

#header-controls {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

select, button {
  font-family: var(--font);
  font-size: 0.72rem;
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 4px 8px;
  cursor: pointer;
  transition: border-color 0.15s, color 0.15s;
}

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

select:focus, button:focus {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

#scoreboard {
  display: flex;
  gap: 20px;
  font-size: 0.82rem;
  color: var(--muted);
}

#scoreboard strong {
  color: var(--accent);
}

/* ── Canvas ──────────────────────────────────────────────── */

#canvas-container {
  flex: 1 1 auto;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

#game-canvas {
  display: block;
  image-rendering: pixelated;
  border: 2px solid var(--border);
  border-radius: var(--radius);
}

/* ── Footer ──────────────────────────────────────────────── */

#footer {
  flex-shrink: 0;
  text-align: center;
}

#controls-hint {
  font-size: 0.68rem;
  color: var(--muted);
  letter-spacing: 0.04em;
}

/* ── Mobile adjustments ──────────────────────────────────── */

@media (max-width: 400px) {
  #game-title {
    font-size: 1.1rem;
  }

  #header-controls {
    gap: 4px;
  }

  select, button {
    font-size: 0.65rem;
    padding: 3px 6px;
  }
}