How to properly format background image size on password page?

[ManinderSB]

Hello,

I am trying to achieve the correct formatting to the background image on my store password page. 

At the moment I have change the background to an image of my choice but when checking the website the full image is not showing on the page and it seems to have zoomed in alot on the picture?

How can I solve this so the full image is showing as the background image?

Any help and guidance is appreciated!

[ManinderSB]

 bump!