<ul>
        <li class="fruit">Apples</li>
        <li class="fruit">Pears</li>
        <li class="fruit">Oranges</li>
        <li class="fruit">Cherries</li>
 </ul>

var fruits = document.getElementsByClassName('fruit');

fruits[0].style.backgroundColor = 'pink';
fruits[1].style.backgroundColor = 'hotpink';
fruits[2].style.backgroundColor = 'deeppink';
fruits[3].style.backgroundColor = 'palevioletred';