Don't get why this doesn't work

Tell us what’s happening:
I don’t get why this solution doesn’t work. I’ve checked it again and again and it doesn’t clear. The code doesn’t work, even though it’s identical to the video. Any pointers?

Also, the formatting of the code is all wrong, I don’t know how to fix it. But the main point is the #thumbnail part. As far as I can tell, it’s written correctly.

Your code so far

<style>
 h4 {
   text-align: center;
   background-color: rgba(45, 45, 45, 0.1);
   padding: 10px;
   font-size: 27px;
 }

 p {
   text-align: justify;
 }

 .links {
   text-align: left;
   color: black;
 }

 .fullCard {
   width: 245px;
   border: 1px solid #ccc;
   border-radius: 5px;
   margin: 10px 5px;
   padding: 4px;
 }
 .cardContent {
   padding: 10px;
 }
 .cardText {
   margin-bottom: 30px;
 }





#thumbnail: 
 {box-shadow: 0 10px 20px rgba(0,0,0,0.19), 0 6px 6px rgba(0,0,0,0.23);
}

</style>
<div class="fullCard" id="thumbnail">
 <div class="cardContent">
   <div class="cardText">
     <h4>Alphabet</h4>
     <hr>
     <p><em>Google was founded by Larry Page and Sergey Brin while they were <u>Ph.D. students</u> at <strong>Stanford University</strong>.</em></p>
   </div>
   <div class="cardLinks">
     <a href="https://en.wikipedia.org/wiki/Larry_Page" target="_blank" class="links">Larry Page</a><br><br>
     <a href="https://en.wikipedia.org/wiki/Sergey_Brin" target="_blank" class="links">Sergey Brin</a>
   </div>
 </div>
</div>

Challenge: Add a box-shadow to a Card-like Element

Link to the challenge:
https://www.freecodecamp.org/learn/responsive-web-design/applied-visual-design/add-a-box-shadow-to-a-card-like-element

I’ve edited your post for readability. When you enter a code block into a forum post, please precede it with a separate line of three backticks and follow it with a separate line of three backticks to make it easier to read.

See this post to find the backtick on your keyboard. The “preformatted text” tool in the editor (</>) will also add backticks around text.

Note: Backticks are not single quotes.

markdown_Forums

syntax error - is that how you write the selector?

Remove the colon:

#thumbnail {
//Styles here
}

Thanks! I’ll remember the thing about the backticks, and yeah, I went to the next challenge to see how they incorporated the id thumbnail correctly, and saw the colon mistake. Thanks for the help!