style.css

body {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  background-color: black;
}

.container {
  display: grid;
  place-items: center;
}

#tictac {
  display: grid;
  place-items: center;
  grid-template-columns: repeat(3, 1fr);
  width: fit-content;
  height: fit-content;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

#tictac > div {
  height: 100px;
  width: 100px;
  cursor: pointer;
  background-color: #15031b;
  color: white;
  border: 1px solid;
  border-radius: 5px;
}

#won {
  color: white;
  font-size: 30px;
  font-weight: bolder;
  margin-top: 50px;
  background-color: #0093e9;
  background-image: linear-gradient(160deg, #0093e9 0%, #80d0c7 100%);
  padding: 20px;
  border-radius: 10px;
}

#again {
  background-color: #4158d0;
  background-image: linear-gradient(
    43deg,
    #4158d0 0%,
    #c850c0 46%,
    #ffcc70 100%
  );

  height: 50%;
  width: 50%;
  text-align: center;
  font-size: 35px;
  font-weight: bolder;
  line-height: 1.5;
  padding: 10px;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  position: absolute;
  z-index: 10;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  display: none;
}

#again button {
  position: absolute;
  z-index: 12;
  top: 50%;
  left: 50%;
  transform: translate(-50%, 50%);
  font-size: 25px;
  padding: 15px;
  border: none;
  border-radius: 10px;
  cursor: pointer;
}

#again button:hover {
    background-color: #0093e9;
    background-image: linear-gradient(160deg, #0093e9 0%, #80d0c7 100%);
}