I'm using the design manager to build a modular email template with easily customisable modules for our team to quickly change. I'm using tags with predefined content so it can stay the same in case it doesn't have to be changed. The issue I'm facing is that, while in content creator, whenever I'm trying to edit a module (like the white text block below fist CTA) that breaks the email layout.
I copied over and html file with styling done in the <head> and then included the text in white background in a rich text tag, just like this: