Best way to resolve problems that occur only at certain resolutions

this page will display the white news ticker improperly at certain resolutions (by adjusting with ctrl++ and ctrl±). What is the usual route to attacking issues of this nature? Do I need to add a CSS style to the news ticker div or something similar? is it because I have a div within a div?

to see the problem, hit ctrl+0, then hit ctrl++. if that doesnt work, keep hitting ctrl++ or ctrl-- several times and you’ll see the issue with the white news ticker.

Doesn’t look like a resolution problem to me

issue resolved (add relative positioning to the div)