body {
    position: relative;
    margin: 0;
    padding: 0;
}

.scroll-to-top {
    position: fixed;
    bottom: 20px;
    Left: 20px;
    cursor: pointer;
    z-index: 999;
}

.circle {
    width: 50px;
    height: 50px;
    background-color: green;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
}

.arrow {
    width: 0;
    height: 0;
    border-left: 10px solid transparent;
    border-right: 10px solid transparent;
    border-bottom: 20px solid yellow;
    cursor: pointer;
}