Login page : Background size image on Mobile

Hello !

I use a background image in my login page.
It’s perfect on laptop but in mobile, there is this CSS code :

@media (max-width: 767px)
html, body { background-size: contain !important; }

I would like to replace it by “cover”, but I can’t overwrite it because of the !important

How can I do this?

Thank you for your help !

Have a nice day

You must set your CSS (with !important too) and somehow to run it before the original CSS. So your code will be “validated” and all next attempts will not be count by browser.