.cart-button {
    position: sticky;
    /* display: block; */
    margin-top: 20px;
    top: 100px;
    right: 10px;
    float: right;
}

html {
    font-size: 16px;
}

.single-product {
    font-size: 24px;
}

li.product-3 {
    width: 30%;
    margin-left: 15px;
    max-width: 500px;
    float: left;
}