style.css

*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: sans-serif;
    user-select: none;
}
button{
    border: none;
    outline: none;
}
main{
    background:linear-gradient(135deg,#a5aaf7,#e589f3);
}
.container{
    margin: auto;
    width:80%;
    min-height: 100vh;
    display: flex;
    justify-content: space-evenly;
    flex-direction: column;
    align-items: center;
}
.game-container{
    width: 60vmin;
    height: 60vmin;
    border: 2px solid black;
    display: flex;
    justify-content: space-evenly;
    align-items: center;
    flex-wrap: wrap;
    border-radius: 2vmin;
}
.box{
    width: 18vmin;
    height: 18vmin;
    font-size:12vmin;
    font-weight: 100;
    background-color: #e0def4;
    color: #d486b8;
    border-radius: 10px;
}
.box:disabled{
    background-color: #e0def4;
}
.message{
    display: none;
    font-size: 32px;
    text-transform: capitalize;
    color: rgb(0, 0, 0);
}
.reset-btn{
    background-color: white;
    padding: 8px 16px;
    border-radius: 4px;
    user-select: none;
    font-size: 18px;
    font-weight:500;
}

@media (max-width:600px){
    .message{
        font-size: 18px;
    }
    .box{
        font-weight: 400;
    }
}