I put the following CDN code in my HTML file and then executed TimelineLite function in javascript.
<html>
<script src="https://cdnjs.cloudflare.com/ajax/libs/gsap/2.1.2/TweenLite.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/gsap/2.1.2/TimelineMax.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/gsap/2.1.2/easing/EasePack.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/gsap/2.1.2/plugins/CSSPlugin.min.js"></script>
<My javascript code>