html, body {
  height: 90%;
}

body {
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: Arial, sans-serif;
    text-align: center;
    background-color: #000;
}

.container {
    margin: 0 auto;
    padding: 20px;
    max-width: 300px;
}

h1 {
    font-size: 24px;
    color: #fff;
}

.board {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 5px;
    margin: 20px 0;
}

.cell {
    width: 100px;
    height: 100px;
    background-color: #444444;
    color: #fff;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 24px;
    cursor: pointer;
}

button {
    padding: 10px 20px;
    margin-left: 10px;
    background-color: #ff0000;
    color: #fff;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

button:hover {
    background-color: #aa0000;
}

#message {
    background-color: #008000;
    color: #fff;
    margin-bottom: 15px;
    margin-left: 10px;
    padding: 10px 20px;
}