That is because it’s supressed to one line (I’m guessing by minification) and the space/tab elements are conflicting. Try it like this:
[html].asp_main_container{min-width: 240px;}[/html]
that should work.
The margins/padding are added by the parent elements, not the plugin. You could try this custom CSS to reset them to 0:
[html]#top-bar>.flex-row.container,#top-bar>.flex-row.container .header-block {padding: 0 !important;margin: 0 !important;}[/html]
I’m not sure if that is the correct way, you might have to as the theme author as well.