*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html,body{
    height: 100%;
    width: 100%;
}

body{
    background-color: black;
    font-family: monospace;
}

main{
    height: 100%;
    width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 20px;
    anchor-name: --some-anchor;
}

main a{
    color : whitesmoke;
    text-decoration: none;
    padding: 10px 20px;
    z-index: 1;
}

main a:hover{
    anchor-name: --some-anchor;
}

.anchor{
    background-color: #b9b9b9;
    border-radius: 10px;
    position: absolute;
    top: anchor(top);
    left: anchor(left);
    right: anchor(right);
    bottom: anchor(bottom);
    pointer-events: none;
    position-anchor: --some-anchor;
    mix-blend-mode: difference;
    transition: all 0.5s ease-in-out;
}