h1 { font-size: clamp(1.4rem, 5vw, 2.6rem); }

.container {
  position: relative;
  z-index: 10;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
  padding: 20px 20px max(40px, env(safe-area-inset-bottom, 20px)) 20px;
}

/* Override shared .btn for tictactoe's restart button */
.btn {
  font-size: 0.8rem;
  letter-spacing: 0.2em;
  padding: 10px 32px;
  position: relative;
  overflow: hidden;
  transition: color 0.2s, box-shadow 0.2s;
  box-shadow: 0 0 8px rgba(0,245,255,0.2), inset 0 0 8px rgba(0,245,255,0.05);
}
.btn::before {
  content: '';
  position: absolute;
  top: 0; left: -100%;
  width: 100%; height: 100%;
  background: linear-gradient(90deg, transparent, rgba(0,245,255,0.12), transparent);
  transition: left 0.4s;
}
.btn:hover { color: #fff; box-shadow: 0 0 16px rgba(0,245,255,0.5), inset 0 0 16px rgba(0,245,255,0.1); }
.btn:hover::before { left: 100%; }

/* Override shared .ctrl-btn for mode/size toggle buttons */
.ctrl-btn {
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #555a8a;
  background: transparent;
  border: 1px solid #2a2a4a;
  padding: 7px 16px;
  width: auto;
  height: auto;
  display: inline-flex;
  cursor: pointer;
  transition: all 0.2s;
}
.ctrl-btn:active { background: transparent; }
.ctrl-btn:hover:not(.active) { color: #8888bb; border-color: #3a3a6a; }
.ctrl-btn.active          { color: var(--cyan);    border-color: var(--cyan);    box-shadow: 0 0 10px rgba(0,245,255,0.25); }
.ctrl-btn.active.green    { color: #39ff14;        border-color: #39ff14;        box-shadow: 0 0 10px rgba(57,255,20,0.25); }
.ctrl-btn.active.red      { color: var(--magenta); border-color: var(--magenta); box-shadow: 0 0 10px rgba(255,0,160,0.25); }
.ctrl-btn.active.yellow   { color: var(--yellow);  border-color: var(--yellow);  box-shadow: 0 0 10px rgba(245,230,66,0.25); }

.controls { display: flex; flex-direction: column; align-items: center; gap: 8px; }
.btn-row  { display: flex; gap: 8px; }
.hidden   { display: none !important; }

/* Score */
.score {
  display: flex;
  gap: 32px;
  font-family: 'Russo One', sans-serif;
  font-size: 0.85rem;
  letter-spacing: 0.1em;
}
.score-item  { display: flex; flex-direction: column; align-items: center; gap: 4px; }
.score-label { color: #555a8a; font-size: 0.7rem; }
.score-x .score-val { color: var(--magenta); text-shadow: 0 0 12px var(--magenta); }
.score-o .score-val { color: var(--yellow);  text-shadow: 0 0 12px var(--yellow); }
.score-d .score-val { color: #555a8a; }
.score-val  { font-size: 1.6rem; font-weight: 700; }

/* Status */
.status {
  font-size: 1rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  min-height: 1.4em;
  transition: color 0.3s;
}
.status.x-turn { color: var(--magenta); text-shadow: 0 0 10px var(--magenta); }
.status.o-turn { color: var(--yellow);  text-shadow: 0 0 10px var(--yellow); }
.status.draw   { color: #888; }
.status.x-win  { color: var(--magenta); text-shadow: 0 0 16px var(--magenta), 0 0 40px var(--magenta); animation: pulse .6s infinite alternate; }
.status.o-win  { color: var(--yellow);  text-shadow: 0 0 16px var(--yellow),  0 0 40px var(--yellow);  animation: pulse .6s infinite alternate; }

@keyframes pulse { from { opacity: 1; } to { opacity: .6; } }

/* Board */
.board {
  display: grid;
  gap: 5px;
  padding: 5px;
  background: rgba(0,245,255,0.06);
  border: 1px solid rgba(0,245,255,0.2);
  box-shadow: 0 0 20px rgba(0,245,255,0.1), inset 0 0 20px rgba(0,0,0,0.5);
  transition: opacity 0.2s;
}
.board.size-3 { grid-template-columns: repeat(3, 1fr); }
.board.size-5 { grid-template-columns: repeat(5, 1fr); }
.board.thinking { opacity: 0.65; pointer-events: none; }

.cell {
  background: rgba(10,10,30,0.8);
  border: 1px solid rgba(0,245,255,0.15);
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: 'Russo One', sans-serif;
  font-weight: 900;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s;
  position: relative;
  overflow: hidden;
  user-select: none;
}
.board.size-3 .cell { width: clamp(88px,22vw,128px); height: clamp(88px,22vw,128px); font-size: clamp(2rem,8vw,3.4rem); }
.board.size-5 .cell { width: clamp(58px,13vw,82px);  height: clamp(58px,13vw,82px);  font-size: clamp(1.2rem,4vw,2rem); }

.cell::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at center, transparent 60%, rgba(0,245,255,0.04));
  opacity: 0;
  transition: opacity 0.2s;
}
.cell:hover:not(.taken) { background: rgba(0,245,255,0.06); border-color: rgba(0,245,255,0.4); }
.cell:hover:not(.taken)::before { opacity: 1; }
.cell.taken { cursor: default; }

.cell.x { color: var(--magenta); text-shadow: 0 0 12px var(--magenta), 0 0 30px rgba(255,0,160,0.5); }
.cell.o { color: var(--yellow);  text-shadow: 0 0 12px var(--yellow),  0 0 30px rgba(245,230,66,0.5); }

.cell.win-cell.x { background: rgba(255,0,160,0.1); border-color: var(--magenta); box-shadow: inset 0 0 20px rgba(255,0,160,0.15), 0 0 12px rgba(255,0,160,0.3); animation: win-flash .4s ease-out; }
.cell.win-cell.o { background: rgba(245,230,66,0.1); border-color: var(--yellow);  box-shadow: inset 0 0 20px rgba(245,230,66,0.15), 0 0 12px rgba(245,230,66,0.3); animation: win-flash .4s ease-out; }

@keyframes win-flash { from { opacity: 0; transform: scale(.85); } to { opacity: 1; transform: scale(1); } }
.cell.pop { animation: pop .2s ease-out; }
@keyframes pop { 0% { transform: scale(.5); opacity: .4; } 80% { transform: scale(1.08); } 100% { transform: scale(1); opacity: 1; } }

@media (max-width: 520px) {
  h1 { display: none; }
  .footer { display: none; }

  .container {
    gap: 8px;
    padding: 10px 12px max(10px, env(safe-area-inset-bottom, 10px));
  }

  .controls { gap: 6px; }
  .btn-row  { gap: 6px; }
  .ctrl-btn { padding: 5px 10px; font-size: 0.58rem; letter-spacing: 0.1em; }

  .score      { gap: 14px; }
  .score-val  { font-size: 1.1rem; }
  .score-label { font-size: 0.52rem; }

  .status { font-size: 0.72rem; min-height: 1.1em; }

  .btn { padding: 7px 20px; font-size: 0.65rem; }

  /* Board takes remaining vertical space */
  .board {
    width: min(90vw, calc(100dvh - 290px));
    aspect-ratio: 1;
  }

  /* Cells fill grid auto — no fixed px */
  .board.size-3 .cell,
  .board.size-5 .cell {
    width: auto;
    height: auto;
    aspect-ratio: 1;
  }
  .board.size-3 .cell { font-size: clamp(1.6rem, 7vw, 3rem); }
  .board.size-5 .cell { font-size: clamp(0.9rem, 4vw, 2rem); }
}