XF 1.5 How to stretch background image?

[KevinEssence]

How do I stretch the background image so it fills the whole screen based on users resolution size? Did it before but forgot and can't seem to find the answer on google, thank you!

https://gyazo.com/2c03274662c3793a8bf3fbb7324d13e3

 

[Paul B]

background-size:cover

 

[KevinEssence]

background-size:cover

extra.css or? :d

 

[Paul B]

Wherever you added the original image.

 

[KevinEssence]

Thank you.