html,
body {
  height: 100%;
}

body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  background: radial-gradient(circle, #c75987 0%, #251b46 75%, #020024 100%);
}

.voltar {
  display: flex;
  justify-content: center;
  align-items: center;
  background-color: aliceblue;
  border-radius: 19px;
  margin: auto;
  width: 10%;
  height: 5%;
}

a {
  text-decoration: none;
}

button {
  padding: 16px 32px;
  border: none;
  color: white;
  background-color: #020024;
  border-radius: 5px;
  cursor: pointer;
}

button:hover {
  opacity: 0.8;
}

.game-over-dialog {
  text-align: center;
  border: none;
  box-shadow: rgba(0, 0, 0, 0.4) 2px 2px 5px;
}
.game-over-message {
  padding: 16px 32px;
  font-size: 32px;
}

.game-body {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100%;
}

.board {
  width: 500px;
  height: 500px;
  font-size: 100px;
  font-weight: bold;
  text-align: center;
  border-spacing: 8px;
}

.cell {
  border: 1px dashed rgba(255, 255, 255, 0.3);
  border-radius: 8px;
  width: calc(100% / 3);
  height: calc(100% / 3);
  color: rgba(255, 255, 255, 0.8);
  text-shadow: rgba(0, 0, 0, 0.5) 2px 2px 3px;
  transition: background-color 0.3s;
}

.cell:hover {
  background-color: rgba(255, 255, 255, 0.1);
}
.cell:hover::after {
  content: var(--current-player, 'X');
  opacity: 0.5;
}

.cell:empty {
  cursor: pointer;
}
.cell:not(:empty) {
  pointer-events: none;
}

@media screen and (max-width: 420px) {
  .voltar {
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: aliceblue;
    border-radius: 19px;
    margin: auto;
    width: 30%;
    height: 5%;
  }

  a {
    text-decoration: none;
  }

  .game-body {
    justify-content: center;
    align-items: center;
    height: 50%;
    width: auto;
  }

  .board {
    width: 250px;
    height: 250px;
    font-size: 100px;
    font-weight: bold;
    text-align: center;
    border-spacing: 8px;
  }

  .cell:hover::after {
    content: none;
    opacity: 0.5;
  }

  .game-over-message {
    padding: 16px 32px;
    font-size: 12px;
  }

  .cell {
    font-size: 50%;
  }
}