<div>내용1</div>
<div>내용2</div>
<div>내용3</div>
* {
    margin: 0;
    padding: 0;
}
div:nth-child(1) {
    background: red;
}
div:nth-child(2) {
    background: green;
        }
div:nth-child(3) {
    background: blue}
$(document).ready(function() {
  $("div").eq(0).css({padding: 10, "text-align": "center"});
  $("div").css("width", function(index) {
    return index * 100 + 100; // 100, 200, 300
  });
});

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

  1. https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js