I have a spreadsheet which looks like this:
The above is saved as HTML from Excel and consists of the following folder and files:
If I click on the html file it opens as works. If I copy the folder/files onto the server and copy the HTML into a page in BD as Raw HTML, I just get the title and the rest is ignored.
So, the basic user approach of "dump it in and see what happens" has failed.
Any advice on the best (simplest, quickest) way to create a webpage in BackdropCMS?
This is your culprit. What you'll need to do is override these tables using a selector at the top to limit to these tables. Now it could be possible by creating a subtheme, but I know you don't want to do that. There is a module called CSS Injector that could allow just adding an override to this page. Something like:
I agree with the points amilenkov made; this is not going to work well on mobile and there may be better ways to enter this and display this, but if you want to continue with the direction you're going, then CSS Injector and that snippet should work. I've tested with a Chrome extension.
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