Change Font Size or Width

First, thanks for a great plugin – second, I am having a problem that just started – previously the menu fit on one bar line now it is going to two lines – I changed nothing in the options – also it seems to work somewhat sporadically.

I thought I would simply change the font but that hasn’t worked and it is not filling the container in my theme.

Thanks for your help!

https://ww.wp.xz.cn/plugins/widgetize-navigation-menu/