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CSS CSS - Beyond the Basics Understanding CSS Transitions and Transforms Transitions Challenge

Daniel Tofan
Daniel Tofan
40,910 Points

Can you explain why "transition-duration: 0.4s;" is wrong???

transition-duration: 0.4s;

/* Complete the challenge by writing CSS below */

.button {  
  background: #4682B4;

.button:hover {
    background: #356690;
<!DOCTYPE html>
    <title>CSS Transitions</title>
    <link rel="stylesheet" href="page.css">
    <link rel="stylesheet" href="style.css">
    <a class="button" href="#">Learn More</a>

2 Answers

Jonathan Grieve
Jonathan Grieve
Treehouse Moderator 91,253 Points

Hi Daniel,

I can't seem to find it in your CSS code, Would you be able to post it?

Typically though it goes in the .button selector so it can transition back and forth. I don't think 0.4s would be an incorrect value in real life but the challenge is looking for a value of .4s not 0.4s.

Hope this helps. :)

Daniel Tofan
Daniel Tofan
40,910 Points

I know. The challenge validator is badly written. 0.4 is a valid number. I've seen several of these in various courses.