:root {
  --bg: #0f1220;
  --panel: #171b2f;
  --panel-2: #1d2340;
  --cell: #232844;
  --grid: rgba(255,255,255,.08);
  --text: #eef1ff;
  --muted: #9aa4d6;
  --accent: #79d6ff;
  --accent-2: #9b8cff;
  --danger: #ff7b9c;
  --shadow: 0 18px 40px rgba(0, 0, 0, .35);
  --radius: 22px;
  --cell-size: clamp(30px, 5vw, 46px);
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background:
    radial-gradient(circle at top, #20264a 0%, #111527 45%, #090b14 100%);
  color: var(--text);
}

button { font: inherit; }

.app {
  min-height: 100%;
  padding: 24px;
  display: grid;
  gap: 20px;
  max-width: 1100px;
  margin: 0 auto;
}

.topbar {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  align-items: end;
  padding: 18px 20px;
  background: rgba(23, 27, 47, .82);
  border: 1px solid rgba(255,255,255,.08);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  backdrop-filter: blur(12px);
}

.topbar h1 {
  margin: 0 0 6px;
  font-size: 2rem;
}

.topbar p {
  margin: 0;
  color: var(--muted);
}

.stats {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.stat {
  min-width: 90px;
  padding: 12px 14px;
  border-radius: 16px;
  background: rgba(255,255,255,.05);
  border: 1px solid rgba(255,255,255,.07);
  text-align: center;
}

.stat span {
  display: block;
  font-size: .78rem;
  color: var(--muted);
  margin-bottom: 4px;
}

.stat strong {
  font-size: 1.2rem;
}

.btn {
  border: 0;
  border-radius: 14px;
  padding: 12px 16px;
  color: #0a1020;
  background: linear-gradient(135deg, #8ee6ff, #b8a6ff);
  cursor: pointer;
  font-weight: 700;
  box-shadow: 0 10px 20px rgba(0,0,0,.22);
}

.btn:hover { filter: brightness(1.05); }
.btn.primary { min-width: 140px; }

.playfield {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: 20px;
  align-items: start;
}

.board-wrap {
  position: relative;
  display: grid;
  place-items: center;
  padding: 18px;
  background: rgba(23, 27, 47, .82);
  border: 1px solid rgba(255,255,255,.08);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.board {
  display: grid;
  grid-template-columns: repeat(8, var(--cell-size));
  grid-template-rows: repeat(8, var(--cell-size));
  gap: 6px;
  padding: 10px;
  border-radius: 20px;
  background: rgba(255,255,255,.03);
}

.cell {
  width: var(--cell-size);
  height: var(--cell-size);
  border-radius: 10px;
  background: var(--cell);
  border: 1px solid var(--grid);
  transition: transform .08s ease, filter .12s ease, background .12s ease;
}

.cell.filled {
  border-color: rgba(255,255,255,.12);
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.08);
}

.cell.preview-valid {
  outline: 2px solid rgba(126, 255, 199, .9);
  outline-offset: -2px;
  filter: brightness(1.08);
}

.cell.preview-invalid {
  outline: 2px solid rgba(255, 123, 156, .9);
  outline-offset: -2px;
}

.cell:hover {
  transform: translateY(-1px);
}

.sidebar {
  display: grid;
  gap: 16px;
}

.panel {
  background: rgba(23, 27, 47, .82);
  border: 1px solid rgba(255,255,255,.08);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px;
}

.panel h2 {
  margin: 0 0 12px;
  font-size: 1.05rem;
}

.pieces {
  display: grid;
  gap: 12px;
}

.piece {
  width: 100%;
  border: 1px solid rgba(255,255,255,.08);
  background: rgba(255,255,255,.04);
  color: var(--text);
  border-radius: 18px;
  padding: 12px;
  display: grid;
  gap: 10px;
  cursor: pointer;
  text-align: left;
  transition: transform .12s ease, border-color .12s ease, background .12s ease;
}

.piece:hover { transform: translateY(-2px); }
.piece.selected {
  border-color: rgba(126, 214, 255, .75);
  background: rgba(121, 214, 255, .08);
}
.piece.empty {
  cursor: default;
  opacity: .65;
}

.piece-grid {
  display: grid;
  justify-content: start;
  gap: 4px;
}

.piece-cell {
  width: 18px;
  height: 18px;
  border-radius: 6px;
  background: transparent;
}

.piece-cell.block {
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.18);
}

.piece-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--muted);
  font-size: .9rem;
}

.tips ul {
  margin: 0;
  padding-left: 18px;
  color: var(--muted);
  display: grid;
  gap: 8px;
}

.message-panel {
  color: var(--muted);
  min-height: 72px;
  display: flex;
  align-items: center;
}

.overlay {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  background: rgba(7, 10, 20, .68);
  backdrop-filter: blur(6px);
  border-radius: var(--radius);
}

.overlay.hidden { display: none; }

.gameover-card {
  text-align: center;
  padding: 24px;
  border-radius: 24px;
  background: rgba(23, 27, 47, .95);
  border: 1px solid rgba(255,255,255,.1);
  box-shadow: var(--shadow);
}

.new-record-badge {
  display: inline-block;
  margin-bottom: 12px;
  padding: 8px 20px;
  border-radius: 999px;
  background: linear-gradient(135deg, #ffd700, #ffaa00);
  color: #1a0f00;
  font-weight: 800;
  font-size: 1rem;
  letter-spacing: .03em;
  box-shadow: 0 0 18px rgba(255, 200, 0, .55);
  animation: recordPulse 1s ease-in-out infinite alternate;
}

.new-record-badge.hidden { display: none; }

@keyframes recordPulse {
  from { box-shadow: 0 0 12px rgba(255, 200, 0, .4); transform: scale(1); }
  to   { box-shadow: 0 0 28px rgba(255, 200, 0, .8); transform: scale(1.04); }
}

.gameover-card h2 { margin: 0 0 8px; }
.gameover-card p { margin: 0 0 16px; color: var(--muted); }

.final-scores {
  display: flex;
  gap: 16px;
  justify-content: center;
  margin-bottom: 20px;
}

.final-stat {
  padding: 12px 20px;
  border-radius: 14px;
  background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.1);
  min-width: 90px;
}

.final-stat span {
  display: block;
  font-size: .75rem;
  color: var(--muted);
  margin-bottom: 4px;
}

.final-stat strong {
  font-size: 1.4rem;
  color: var(--text);
}

.final-stat.best strong {
  color: var(--accent);
}

@media (max-width: 920px) {
  .playfield {
    grid-template-columns: 1fr;
  }

  .sidebar {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (max-width: 640px) {
  .app { padding: 14px; }
  .topbar {
    flex-direction: column;
    align-items: start;
  }
  .sidebar { grid-template-columns: 1fr; }
  .board {
    gap: 4px;
    padding: 8px;
  }
}