style.css

*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: serif;
}
html,body{
    height: 100vh;
    width: 100vw;
    display: flex;flex-direction: column; align-items: center;justify-content: center;gap: 50px;
    background: #264745;
    color: #3a6b69;
    overflow: hidden;
}
h1{
    position: absolute;
    width: 50vw;
    height: 20vw;
    background-color: #0f1d1c;
    color: white;
    border: 2px solid #3a6b69;
    border-radius: 20px;
    font-size: 3.5vw;
    font-family: serif;
    display: flex;
    align-items: center;justify-content: center;
    flex-direction: column;
    opacity: 1;
    left: 100%;
    transition: all linear 0.5s;
}

h2{
    font-size: 5vw;
}
h2::selection{
    display: none;
}
#main{
    height: 300px;
    width: 300px;
}
.boardrow{
    display: flex;
    width: 100%;
    height: 33.33%;
}
.square{
    width: 33.33%;height: 100%;
    display: flex;align-items: center;justify-content: center;
    border: 1px solid #2F5755;
    font-size: 350%;
    cursor: pointer;
    border-radius: 10px;
    color: #0f1d1c;
}
#reset{
    width: 100px;height: 40px;
    background-color: #2F5755;
    color: white;
    font-size: 100%;
    border-radius: 20px;
    cursor: pointer;
}