Why doesn't anything show up in the block beside the code editor?

Tell us what’s happening:
It said I passed the challenge but nothing visual shows up in the box to the right. Why?

Your code so far

  div:hover { 
    transform: scale(1.1);
    width: 70%;
    height: 100px;
    margin:  50px auto;
    background: linear-gradient(


Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.131 Safari/537.36.

Link to the challenge:

So you were supposed to add/create a div:hover rule, not modify the existing div rule that was there.