/* ===== Tic Tac Toe — game UI =====
   Colours come from the center's shared --gc-* tokens (base.css), so this
   page follows light/dark automatically. Only layout/sizing lives here. */

.wrap {
  max-width: 460px;
  margin: 0 auto;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
  padding: clamp(24px, 6vw, 48px) 20px 40px;
  text-align: center;
}
.head .title { margin: 0; font-size: clamp(26px, 6vw, 34px); letter-spacing: -.02em; }
.head .sub { margin: 4px 0 0; color: var(--gc-text-muted); font-weight: 600; min-height: 1.4em; }

/* Mode / difficulty segmented controls */
.segmented { display: inline-flex; padding: 4px; gap: 4px; background: var(--gc-surface-2); border: 1px solid var(--gc-border); border-radius: 999px; }
.segmented--sub { margin-top: -8px; }
.seg {
  appearance: none; border: 0; cursor: pointer;
  font: inherit; font-size: 13.5px; font-weight: 600;
  padding: 8px 16px; border-radius: 999px;
  background: transparent; color: var(--gc-text-muted);
  transition: background .15s ease, color .15s ease;
}
.seg--sm { padding: 5px 12px; font-size: 12.5px; }
.seg:hover { color: var(--gc-text); }
.seg[aria-selected="true"] { background: var(--gc-accent); color: var(--gc-on-accent); box-shadow: var(--gc-shadow); }
.seg:focus-visible { outline: none; box-shadow: var(--gc-ring); }

/* Board */
.board {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  grid-template-rows: repeat(3, minmax(0, 1fr));
  gap: 10px;
  width: min(90vw, 340px);
  aspect-ratio: 1 / 1;
}
.cell {
  appearance: none;
  border: 1px solid var(--gc-border);
  border-radius: 16px;
  background: var(--gc-surface);
  box-shadow: var(--gc-shadow);
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  /* minmax(0,1fr) already pins the track; aspect-ratio keeps each box square
     and overflow:hidden guarantees content can never resize the cell. */
  width: 100%; height: 100%; min-width: 0; min-height: 0;
  overflow: hidden;
  font: inherit;
  font-size: clamp(38px, 16vw, 60px);
  line-height: 1;
  color: var(--gc-text);
  transition: transform .12s ease, box-shadow .12s ease, border-color .12s ease, background .12s ease;
}
.cell:not(.cell--filled):hover { transform: translateY(-2px); border-color: var(--gc-accent); box-shadow: var(--gc-shadow-hi); }
.cell:focus-visible { outline: none; box-shadow: var(--gc-ring); }
.cell:disabled { cursor: default; }
.cell--x { color: var(--gc-accent); }
.cell--o { color: var(--gc-accent-2); }
.cell--win { background: color-mix(in srgb, var(--gc-accent) 14%, var(--gc-surface)); border-color: var(--gc-accent); animation: pop .25s ease; }
.cell--hint { animation: pop .25s ease; }
@keyframes pop { from { transform: scale(.82); } }

/* Scoreboard */
.scores { display: flex; gap: 10px; width: 100%; }
.score {
  flex: 1;
  display: flex; flex-direction: column; gap: 2px;
  padding: 10px 8px;
  background: var(--gc-surface); border: 1px solid var(--gc-border); border-radius: 12px;
}
.score__k { font-size: 12px; color: var(--gc-text-muted); font-weight: 600; }
.score__v { font-size: 22px; font-weight: 700; font-variant-numeric: tabular-nums; }

/* Controls */
.controls { display: flex; gap: 10px; }
.btn {
  appearance: none; cursor: pointer; font: inherit; font-size: 14px; font-weight: 600;
  padding: 10px 18px; border-radius: 10px;
  border: 1px solid var(--gc-border); background: var(--gc-surface); color: var(--gc-text);
  transition: transform .06s ease, background .15s ease, border-color .15s ease;
}
.btn:hover { border-color: var(--gc-accent); }
.btn:active { transform: translateY(1px); }
.btn:focus-visible { outline: none; box-shadow: var(--gc-ring); }
.btn--primary { background: var(--gc-accent); border-color: var(--gc-accent); color: var(--gc-on-accent); }
.btn--primary:hover { filter: brightness(1.05); }

@media (prefers-reduced-motion: reduce) {
  .cell, .cell--win, .cell--hint { transition: none; animation: none; transform: none; }
}