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                <!DOCTYPE html>

  <meta charset="utf-8" />
  <title>Web Design - CSS Background-color, Border-radius, Transition, and Transform Properties Experiment</title>

  <section id="container">
    <h2>Colored Boxes</h2>
    <p>Red box with Opacity set to 1 (fully opaque) and border radius set to 25px.</p>
    <div id="one">

    <p>Blue box with Opacity set to 0.3 (so, on top of the reddish background, it looks purple).</p>
    <div id="two">


    <p><strong>Hover over the green box below.</strong><br>[Green box with transition set to margin-left 2s and transform set to 2s. Also, on hover, transform perspective(.5em) is set. This causes the perspective to transform to .5em distance from the user to the z=0 plane. And, on hover, transform: rotateX(3deg) is set. This causes only the x-axis to rotate 3 degrees, making the box appear to transform into a trapezoid.]</p>

    <div id="three">




                #container {
  height: 750px;
  width: 750px;
  background: url("");

div {
  height: 100px;
  width: 100px;

h2 {
  font-family: "HelveticaNeue-Light", "Helvetica Neue Light", "Helvetica Neue",
    Helvetica, Arial, "Lucida Grande", sans-serif;
  font-weight: 300;
  color: rgba(255, 255, 255, 1);

#one {
  background-color: rgba(255, 0, 0, 1);
  border-radius: 25px;

#two {
  background-color: rgba(0, 0, 255, 0.3);

#three {
  background-color: rgba(0, 255, 0, 1);
  -webkit-transition: margin-left 2s, transform 2s;
  /* Safari */
  transition: margin-left 2s, transform 2s;

#three:hover {
  background-color: rgba(0, 255, 0, 1);
  margin-left: 50px;
  -webkit-transform: perspective(0.5em) rotateX(3deg);
  /* Safari */
  transform: perspective(0.5em) rotateX(3deg);