Border-Radius in CSS not working. [SOLVED]

Question

I cannot for the life of me get border-radius to work... It always gets crossed out (In chrome) or ignored (SoloLearn).
https://code.sololearn.com/WTo0F83dwrK6/#html
^ ^ ^ Above is the link to the code playground. Can anyone help me out with this?
P.S. Above is ALL of the code for both HTML and CSS. They both are the entirety of the HTML/CSS file.
SOLVED: Thank you guys so much! It turns out that it should be border-radius: 20px 20px 20px 20px; (Or just border-radius: 20px;)
Also with the semicolons, I know... I just keep forgetting to add them... =-\. Thanks all! =-D

Answer 1

Remove the commas from border radius values

Answer 2

How it will work bro dont use , there to separate 2 values .ok secondly use ; at the end

Answer 3

border-radius: 20px;
not
border-radius: 20px, 20px, 20px, 20px;
Dawson Graham

Answer 4

Remove the , from the border-radius and also remember to add ; at the end.

Answer 5

And when passing the same value for
Border-radius: top right bottom left;
You can just pass a single value and it applies to all...
Border-radius:20px;