standardize Vaadin form widths in Vaadin 14 Java API

I notice that when I use LoginForm it has a default size. I can’t quite figure out how it gets this size. I would like to standardize all my forms, e.g. FormLayout and LoginForm. I do not mind making my FormLayouts match the size of the LoginForm -or- set the LoginForm and FormLayouts to my own preset size. The problem is that when I set the LoginForm’s width as a percentage, it never seems to match the same size as the FormLayouts… the LoginForm always comes out smaller for the same percentage.

Is there any way to set my LoginForms and FormLayouts to have the same width consistently?

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