body {
    margin: 0;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(white, silver);
}

ul {
    padding: 0;
}

ul:nth-child(1) {--rate: 1.5; --bgcolor: black;}
ul:nth-child(2) {--rate: 1.732; --bgcolor: brown;}
ul:nth-child(3) {--rate: 2; --bgcolor: green;}

ul li {
    --h: 3em;
    list-style-type: none;
    width: calc(var(--h) * var(--rate));
    height: var(--h);
    background-color: var(--bgcolor);
    color: white;
    font-family: sans-serif;
    text-align: center;
    line-height: var(--h);
    position: relative;
    margin: 2em;
}

ul li::before,
ul li::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: inherit;
    height: inherit;
    background-color: inherit;
    z-index: -1;
    filter: opacity(0);
    transition: 0.3s;
}

ul li:hover::before,
ul li:hover::after {
    filter: opacity(1);
    transform: rotate(calc(60deg * var(--direction)));
}

ul li::before{--direction: 1;}
ul li::after{--direction: -1; transition-delay: 0.1s;}