:root {
  --go-line: rgba(15, 23, 42, 0.12);
  --go-x: rgba(239, 68, 68, 0.96);
  --go-o: rgba(37, 99, 235, 0.96);
}

.goStatus {
  margin: 10px 0 14px;
  font-size: 14px;
  font-weight: 800;
  background: rgba(15, 23, 42, 0.04);
  border: 1px solid rgba(15, 23, 42, 0.06);
  padding: 10px 12px;
  border-radius: 999px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}

.goSep {
  opacity: 0.55;
  margin: 0 4px;
}

.goDiffLabel {
  font-size: 12px;
  font-weight: 900;
  color: rgba(15, 23, 42, 0.68);
  white-space: nowrap;
}

.goDiffGrid {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: 10px;
  gap: 4px;
  padding: 4px 6px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.55);
  border: 1px solid rgba(15, 23, 42, 0.10);
}

.goDiffDot {
  width: 10px;
  height: 10px;
  border-radius: 3px;
  border: 1px solid rgba(15, 23, 42, 0.22);
  background: rgba(255, 255, 255, 0.55);
}

.goDiffDot.isOn {
  background: rgba(15, 23, 42, 0.92);
  border-color: rgba(15, 23, 42, 0.92);
}

.goBoard {
  width: min(460px, 100%);
  aspect-ratio: 1 / 1;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(8, 1fr);
  grid-template-rows: repeat(8, 1fr);
  border: 3px solid var(--go-line);
  border-radius: 18px;
  overflow: hidden;
  background: #fff;
  box-shadow: var(--shadow-soft);
}

.goCell {
  appearance: none;
  border: 0;
  padding: 0;
  background: linear-gradient(180deg, #ffffff, #f8fafc);
  border-right: 2px solid var(--go-line);
  border-bottom: 2px solid var(--go-line);
  cursor: pointer;
  width: 100%;
  height: 100%;
  touch-action: manipulation;
  user-select: none;
  position: relative;
  transition: filter 160ms ease, transform 90ms ease, background 160ms ease;
}

.goCell:nth-child(8n) {
  border-right: 0;
}
.goCell:nth-last-child(-n + 8) {
  border-bottom: 0;
}

.goCell:active {
  transform: scale(0.985);
}

.goCell:disabled {
  cursor: not-allowed;
  opacity: 0.98;
}

.goMark {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  font-weight: 1000;
  font-size: clamp(26px, 7.4vw, 52px);
  line-height: 1;
  transform: translateZ(0);
  text-shadow: 0 10px 20px rgba(2, 6, 23, 0.10);
}

.goMark.x {
  color: var(--go-x);
}
.goMark.o {
  color: var(--go-o);
  -webkit-text-stroke: 1.2px rgba(37, 99, 235, 0.96);
  text-stroke: 1.2px rgba(37, 99, 235, 0.96);
}

.goMark.about {
  opacity: 0.35;
  filter: saturate(0.6) brightness(1.08);
}

.goMark.fading {
  animation: goVanish 260ms ease-out forwards;
}

@keyframes goVanish {
  from {
    opacity: 0.35;
  }
  to {
    opacity: 0;
  }
}

.goCell.win {
  background: #fef9c3;
}

@media (max-width: 420px) {
  .goStatus {
    margin: 8px 0 10px;
    padding: 8px 10px;
    font-size: 13px;
  }
  .goDiffLabel {
    font-size: 11px;
  }
  .goDiffGrid {
    grid-auto-columns: 9px;
    gap: 3px;
    padding: 3px 5px;
  }
  .goDiffDot {
    width: 9px;
    height: 9px;
    border-radius: 3px;
  }
  .goBoard {
    border-radius: 16px;
    height: min(380px, 86vw);
  }
  .goCell {
    border-right: 2px solid var(--go-line);
    border-bottom: 2px solid var(--go-line);
  }
}