W3Schools Tryit Editor

<!DOCTYPE html>
<html>
<title>W3.CSS</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="4/w3.css">
<link rel="stylesheet" href="../lib/w3-theme-blue.css">
<style>
.w3-theme-gradient {
  color: #000 !important;
  background:-webkit-linear-gradient(top,#64B5F6 25%,#42A5F5 75%)}
.w3-theme-gradient {
  color: #000 !important;
  background:-moz-linear-gradient(top,#64B5F6 25%,#42A5F5 75%)}
.w3-theme-gradient {
  color: #000 !important;
  background:-o-linear-gradient(top,#64B5F6 25%,#42A5F5 75%)}
.w3-theme-gradient {
  color: #000 !important;
  background:-ms-linear-gradient(top,#64B5F6 25%,#42A5F5 75%)}
.w3-theme-gradient {
  color: #000 !important;
  background: linear-gradient(top,#64B5F6 25%,#42A5F5 75%)}
</style>
<body>

<div class="w3-container w3-text-theme">
<h2>w3-text-theme</h2></div>

<ul class="w3-ul w3-border-top">
  <li class="w3-theme-l5">
  <a class="w3-button w3-xlarge w3-circle w3-theme-action"
  style="position:fixed;top:48px;right:24px;">+</a>
  <p>w3-theme-l5 (w3-theme-light)</p>
  </li>
  <li class="w3-theme-l4">
    <p>w3-theme-l4</p>
  </li>
  <li class="w3-theme-l3">
    <p>w3-theme-l3</p>
  </li>
  <li class="w3-theme-l2">
    <p>w3-theme-l2</p>
  </li>
  <li class="w3-theme-l1">
    <p>w3-theme-l1</p>
  </li>
  <li class="w3-theme">
    <p>w3-theme</p>
  </li>
  <li class="w3-theme-d1">
    <p>w3-theme-d1</p>
  </li>
  <li class="w3-theme-d2">
    <p>w3-theme-d2</p>
  </li>
  <li class="w3-theme-d3">
    <p>w3-theme-d3</p>
  </li>
  <li class="w3-theme-d4">
    <p>w3-theme-d4 (w3-theme-dark)</p>
  </li>
  <li class="w3-theme-gradient">
    <p>w3-theme-gradient</p>
  </li>
</ul>
</div>

</body>

</html>