* { box-sizing: border-box; margin: 0; padding: 0; }
html, body {
  width: 100%;
  height: 100%;
  background: #0b1020;
  color: #f4f7ff;
  font-family: "Segoe UI", system-ui, sans-serif;
  overflow: hidden;
}
#game-container {
  position: relative;
  width: 100%;
  height: 100%;
  display: flex;
  align-items: stretch;
  justify-content: stretch;
}
#game-container::before,
#game-container::after {
  content: none;
}
#gameCanvas {
  display: block;
  width: 100%;
  height: 100%;
  background: #121a2f;
}
.overlay {
  position: absolute;
  inset: 0;
  z-index: 4;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
  background: rgba(8, 12, 24, 0.72);
  text-align: center;
  padding: 24px;
}
.overlay.hidden { display: none; }
#game-title {
  font-size: clamp(1.6rem, 4vw, 2.4rem);
  letter-spacing: 0.04em;
}
#controls-hint {
  opacity: 0.8;
  font-size: 0.95rem;
}
#startButton {
  appearance: none;
  border: 0;
  border-radius: 999px;
  padding: 12px 28px;
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: #0b1020;
  background: linear-gradient(135deg, #7dd3fc, #a78bfa);
  cursor: pointer;
}
#startButton:hover { filter: brightness(1.08); }
#startButton:focus-visible {
  outline: 2px solid #fff;
  outline-offset: 3px;
}