h1 { font-size: clamp(1.6rem, 8vw, 2.4rem); }

.wrapper {
  position: relative;
  z-index: 10;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
  padding: 24px 16px max(32px, env(safe-area-inset-bottom, 16px)) 16px;
}

.top-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  width: 100%;
  max-width: 420px;
  justify-content: space-between;
}

.score-panels {
  display: flex;
  gap: 8px;
}

.board-wrap {
  position: relative;
}

.grid {
  --cell: 90px;
  --gap: 10px;
  display: grid;
  grid-template-columns: repeat(4, var(--cell));
  grid-template-rows: repeat(4, var(--cell));
  gap: var(--gap);
  padding: var(--gap);
  background: rgba(0, 245, 255, 0.04);
  border: 1px solid rgba(0, 245, 255, 0.2);
  box-shadow: 0 0 24px rgba(0, 245, 255, 0.08);
}

.cell {
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: 'Russo One', sans-serif;
  font-weight: 700;
  border: 1px solid rgba(0, 245, 255, 0.1);
  background: rgba(0, 245, 255, 0.02);
  color: transparent;
  transition: background 0.08s, color 0.08s, box-shadow 0.08s;
  user-select: none;
}

@keyframes cell-appear {
  0%   { transform: scale(0.4); opacity: 0; }
  60%  { transform: scale(1.1); }
  100% { transform: scale(1);   opacity: 1; }
}

@keyframes cell-merge {
  0%   { transform: scale(1); }
  40%  { transform: scale(1.18); }
  100% { transform: scale(1); }
}

.cell.appear { animation: cell-appear 0.16s ease forwards; }
.cell.merge  { animation: cell-merge  0.12s ease forwards; }

.overlay {
  position: absolute;
  inset: 0;
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
  background: rgba(5, 5, 16, 0.88);
  z-index: 20;
}

.overlay-btns {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  justify-content: center;
}

.hint {
  font-size: 0.6rem;
  letter-spacing: 0.12em;
  color: #2a2a4a;
  text-transform: uppercase;
}

@media (max-width: 520px) {
  h1 { display: none; }
  .wrapper { gap: 14px; padding-top: 14px; }
}

@media (max-width: 440px) {
  .grid {
    --cell: 70px;
    --gap: 8px;
  }
  .top-bar { max-width: 340px; }
}

@media (max-width: 360px) {
  .grid {
    --cell: 60px;
    --gap: 6px;
  }
}