Issues with footer_8 Layout on Subscribe Form: Troubleshooting Help Needed

Hey all I'm seeing some weirdness with footer_8 on the subscribe form. the other day i implemented this component on a site and all was well it matched the layout that is shown in the screenshot of the component page where the input and button are on the same row. but now the input is stretching to fill the container causing the button to wrap underneath. i'm seeing it happen on the component page preview as well. any thoughts? i was playing about with the grid alignment but no luck. i'm a little stumped on this one