freeCodeCamp Challenge Guide: Learn How the CSS @keyframes and animation Properties Work

Learn How the CSS @keyframes and animation Properties Work

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Problem Explanation

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Hint 1

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Hint 2

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Solution 1 (Click to Show/Hide)
  div {
    height: 40px;
    width: 70%;
    background: black;
    margin: 50px auto;
    border-radius: 5px;

  #rect {
    animation-name: rainbow;
    animation-duration: 4s;

  @keyframes rainbow {
    0% {
      background-color: blue;
    50% {
      background-color: green;
    100% {
      background-color: yellow;

<div id="rect"></div>

Code Explanation

  • Code explanation goes here

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