Animation-fill-mode VS. transition

Tell us what’s happening:

If I can accomplish the same thing with less code like so:

button:hover {

Why am I setting @keyframes and using animation properties? The expected solution seems overly complex.

Your code so far

  button {
    border-radius: 5px;
    color: white;
    background-color: #0F5897;
    padding: 5px 10px 8px 10px;
  button:hover {
    animation-name: background-color;
    animation-duration: 500ms;
    /* add your code below this line */
    /* add your code above this line */
  @keyframes background-color {
    100% {
      background-color: #4791d0;

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User Agent is: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_3) AppleWebKit/604.5.6 (KHTML, like Gecko) Version/11.0.3 Safari/604.5.6.

Link to the challenge:

Don’t use animation when you dont need it)
Animation gives you more control over keyframes