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

html, body {
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: #060a14;
}

body {
  font-family: 'Segoe UI', system-ui, sans-serif;
  color: #d8e4f0;
}

#game-root {
  width: 100vw;
  height: 100vh;
  position: relative;
}

#game-container {
  width: 100%;
  height: 100%;
  line-height: 0;
}

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

.hud {
  position: absolute;
  inset: 0;
  pointer-events: none;
  z-index: 10;
}

.hud-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  padding: 12px 16px;
  gap: 12px;
}

.hud-panel {
  background: rgba(8, 14, 28, 0.72);
  border: 1px solid rgba(140, 170, 210, 0.2);
  border-radius: 10px;
  padding: 8px 14px;
  backdrop-filter: blur(8px);
  min-width: 120px;
}

.hud-label {
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #7a8fa8;
  margin-bottom: 2px;
}

.hud-value {
  font-size: 1.15rem;
  font-weight: 700;
  color: #e8f0ff;
  font-variant-numeric: tabular-nums;
}

.hud-value.power-rapid { color: #f59e0b; }
.hud-value.power-spread { color: #38bdf8; }
.hud-value.power-mega { color: #a78bfa; }
.hud-value.power-shield { color: #4ade80; }

.hud-controls {
  position: absolute;
  bottom: 12px;
  left: 50%;
  transform: translateX(-50%);
  font-size: 0.68rem;
  color: rgba(180, 200, 230, 0.55);
  background: rgba(8, 14, 28, 0.5);
  padding: 6px 14px;
  border-radius: 100px;
  border: 1px solid rgba(140, 170, 210, 0.12);
  white-space: nowrap;
}

.overlay {
  position: absolute;
  inset: 0;
  display: none;
  align-items: center;
  justify-content: center;
  background: rgba(4, 8, 18, 0.78);
  backdrop-filter: blur(4px);
  z-index: 20;
  pointer-events: auto;
}

.overlay.visible {
  display: flex;
}

.overlay-card {
  text-align: center;
  background: linear-gradient(160deg, rgba(18, 28, 48, 0.95), rgba(10, 16, 30, 0.98));
  border: 1px solid rgba(140, 170, 210, 0.25);
  border-radius: 16px;
  padding: 28px 36px;
  max-width: 90%;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

.overlay-card h2 {
  font-size: 1.5rem;
  font-weight: 700;
  color: #f87171;
  margin-bottom: 8px;
  letter-spacing: 0.04em;
}

.overlay-card p {
  font-size: 0.85rem;
  color: #94a3b8;
  margin-bottom: 6px;
}

.overlay-card .final-score {
  font-size: 1.1rem;
  font-weight: 600;
  color: #e2e8f0;
  margin: 14px 0 18px;
}

.btn-restart {
  font-family: inherit;
  font-size: 0.9rem;
  font-weight: 600;
  padding: 10px 28px;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  background: linear-gradient(135deg, #3b82f6, #2563eb);
  color: #fff;
  box-shadow: 0 4px 16px rgba(37, 99, 235, 0.35);
  transition: transform 0.15s, box-shadow 0.15s;
}

.btn-restart:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(37, 99, 235, 0.45);
}