how do i add a background image to the status/online/you area of the profile?

so ive basically managed to figure out everything else by tinkering with the code in inspect mode or with help of online tuts, but i cant for the life of me figure out how i can put a background behind the status area to the right of my profile picture

i COULD add a floating image and let it be behind the text, but that comes with the issue that depending on the persons device, the placement of that would be messed up (for example, the placement of my hanging key gif shifts when i resize my browser window)

so if anyone has any idea on how i can add a background to the status area and let me know id really appreciate it

thank you so much in advance!