:root {
  --bg: #adf7ff;
  --water: #7bdff2;
  --wave: #9ee9ff;
  --accent: #ffde59;
  --dark: #25527a;
  --text: #113d56;
}

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

body {
  font-family: 'Segoe UI', system-ui, sans-serif;
  background: radial-gradient(circle at top, #c1fbff 0%, #7bdff2 45%, #54c4e2 100%);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 24px;
  color: var(--text);
}

.game-shell {
  width: min(100%, 980px);
  background: rgba(255,255,255,0.95);
  border-radius: 32px;
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.14);
  overflow: hidden;
}

.top-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 24px;
  background: linear-gradient(90deg, #72d7f6 0%, #8cdeff 100%);
  color: #093a59;
  font-size: 1.25rem;
  font-weight: 700;
}

.game-area {
  position: relative;
  background: linear-gradient(to bottom, #a7e3ff 0%, #5ec3e9 100%);
  padding: 20px;
}

#gameCanvas {
  width: 100%;
  border-radius: 24px;
  background: #84dbff;
  display: block;
  box-shadow: inset 0 0 0 4px rgba(255,255,255,0.3);
}

.help-box {
  margin-top: 16px;
  background: rgba(255, 255, 255, 0.92);
  border-radius: 20px;
  padding: 18px;
  font-size: 1rem;
  line-height: 1.6;
}

.controls {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  padding: 20px;
  background: #f7fdff;
}

.controls button {
  border: none;
  border-radius: 18px;
  background: #ffde59;
  color: #113d56;
  font-size: 2rem;
  font-weight: 800;
  padding: 18px 0;
  cursor: pointer;
  transition: transform 0.14s ease, box-shadow 0.14s ease;
}

.controls button:active {
  transform: scale(0.96);
  box-shadow: inset 0 4px 10px rgba(0,0,0,0.12);
}

@media (max-width: 640px) {
  .game-shell {
    width: 100%;
  }

  .top-bar {
    flex-direction: column;
    gap: 8px;
  }

  .controls {
    grid-template-columns: repeat(2, 1fr);
  }
}