#start-game-form #start_game {
    width: 100%;
}

#game-name {
    float: left;
}

#start-game-form {
    max-width: 300px;
}

.center {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 40vh;
    flex-direction: column;
 }