what is js and css code example

Example 1: html css javascript

<!-- Answer to: "html css javascript" -->

<!--
  To keep things simple:
  HTML provides the basic structure of sites, which is enhanced and
  modified by other technologies like CSS and JavaScript. CSS
  is used to control presentation, formatting, and layout.
  JavaScript is used to control the behavior of different elements.
-->

For example:
<!--HTML-->
<div id="me">Click me!</div>
<!--CSS-->
<style>
  div {
    height: 128px; /* Makes the div 128px in height */
    width: 128px; /* Makes the div 128px in width */
    background: red; /* Makes the div's background, red */
  }
</style>
<!--JS-->
<script>
  document.getElementById("me".addEventListener("click", function(){
      document.getElementById("me").style.background = 'blue';
  });
</script>
<!-- If you want to test the code above, go to:https://www.w3schools.com/code/tryit.asp?filename=GDZ0PJDLYQ1V -->

<!--
  For more information, go to:
  https://blog.hubspot.com/marketing/web-design-html-css-javascript
-->

Example 2: css in js

JSS is an authoring tool for CSS which allows you to use JavaScript to describe styles in a declarative, conflict-free and reusable way. It can compile in the browser, server-side or at build time in Node.

JSS is framework agnostic. It consists of multiple packages: the core, plugins, framework integrations and others.