* {
  box-sizing: border-box;
}

:root {
  --bg: #0f1730;
  --panel: #17213f;
  --panel-2: #202c50;
  --text: #f8fafc;
  --muted: #b8c2dc;
  --accent: #ffd76a;
  --accent-2: #7de2d1;
  --danger: #ff7a8b;
  --line: rgba(255,255,255,0.12);
}

html, body {
  margin: 0;
  min-height: 100%;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: radial-gradient(circle at top, #1d2a56 0%, var(--bg) 55%);
  color: var(--text);
}

body {
  min-height: 100vh;
}

button {
  font: inherit;
}

.page-shell {
  width: min(1100px, 100%);
  margin: 0 auto;
  padding: 24px;
}

.game-card {
  background: rgba(23, 33, 63, 0.96);
  border: 1px solid var(--line);
  border-radius: 22px;
  padding: 20px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.28);
}

.game-header {
  display: flex;
  gap: 20px;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 16px;
}

.eyebrow {
  margin: 0 0 3px;
  color: var(--accent-2);
  font-weight: 800;
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1 {
  margin: 0;
  font-size: clamp(2rem, 5vw, 3.3rem);
  line-height: 1;
}

.subtitle {
  margin: 10px 0 0;
  color: var(--muted);
}


.stats-group {
  display: flex;
  gap: 10px;
  flex-shrink: 0;
}

.score-panel {
  min-width: 110px;
  text-align: center;
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 10px 14px;
}

.score-label {
  display: block;
  color: var(--muted);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

#score {
  display: block;
  font-size: 2rem;
  color: var(--accent);
}

.game-wrap {
  position: relative;
  overflow: hidden;
  border-radius: 18px;
  border: 1px solid var(--line);
  background: #0a1022;
}

canvas {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 900 / 520;
  background: linear-gradient(180deg, #111b38, #0b1228);
  touch-action: none;
}

.overlay {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  padding: 20px;
  background: rgba(8, 13, 29, 0.72);
  backdrop-filter: blur(4px);
}

.overlay.hidden {
  display: none;
}

.overlay-card {
  width: min(430px, 92%);
  padding: 26px;
  text-align: center;
  border-radius: 18px;
  background: rgba(23, 33, 63, 0.98);
  border: 1px solid var(--line);
  box-shadow: 0 18px 50px rgba(0,0,0,0.3);
}

.overlay-card h2 {
  margin-top: 0;
  font-size: 1.8rem;
}

.overlay-card p {
  color: var(--muted);
  line-height: 1.55;
}

.controls-row {
  display: flex;
  gap: 10px;
  margin-top: 14px;
  flex-wrap: wrap;
}

.primary-btn,
.secondary-btn,
.move-btn {
  border: 0;
  border-radius: 12px;
  cursor: pointer;
  transition: transform 0.12s ease, filter 0.12s ease;
}

.primary-btn:hover,
.secondary-btn:hover,
.move-btn:hover {
  filter: brightness(1.08);
}

.primary-btn:active,
.secondary-btn:active,
.move-btn:active {
  transform: translateY(1px) scale(0.99);
}

.primary-btn {
  background: var(--accent);
  color: #1a1b20;
  padding: 12px 18px;
  font-weight: 800;
}

.secondary-btn {
  background: var(--panel-2);
  color: var(--text);
  padding: 10px 14px;
  border: 1px solid var(--line);
}

.how-panel,
.leaderboard-section {
  margin-top: 16px;
  padding: 16px;
  border-radius: 16px;
  background: rgba(32, 44, 80, 0.6);
  border: 1px solid var(--line);
}

.how-panel h2,
.leaderboard-section h2 {
  margin-top: 0;
  font-size: 1.05rem;
}

.how-panel p {
  margin: 6px 0;
  color: var(--muted);
}

.mobile-controls {
  display: none;
  width: 210px;
  margin: 18px auto 0;
  grid-template-columns: repeat(3, 62px);
  grid-template-rows: repeat(2, 62px);
  gap: 8px;
  justify-content: center;
}

.move-btn {
  background: var(--panel-2);
  color: var(--text);
  border: 1px solid var(--line);
  font-size: 1.3rem;
  min-height: 54px;
  user-select: none;
  touch-action: none;
}

.move-btn.up { grid-column: 2; grid-row: 1; }
.move-btn.left { grid-column: 1; grid-row: 2; }
.move-btn.down { grid-column: 2; grid-row: 2; }
.move-btn.right { grid-column: 3; grid-row: 2; }

@media (max-width: 760px) {
  .page-shell {
    padding: 10px;
  }

  .game-card {
    padding: 12px;
    border-radius: 16px;
  }

  .game-header {
    align-items: center;
  }

  .subtitle {
    font-size: 0.9rem;
  }

  .score-panel {
    min-width: 78px;
  }

  .stats-group {
    gap: 6px;
  }

  .mobile-controls {
    display: grid;
  }
}

@media (max-width: 520px) {
  .game-header {
    gap: 12px;
  }

  .subtitle {
    display: none;
  }

  .score-panel {
    padding: 8px 10px;
  }
}

@media (max-width: 430px) {
  .score-panel {
    min-width: 68px;
    padding: 7px 8px;
  }

  #score,
  #timer {
    font-size: 1.45rem;
  }
}