Here’s a list of ‘Blank’ theme approaches: No particular recommendations here as I certainly haven’t tried them all - and no guarantees they are all still supported! It’s just a list.
Foundation 6 - https://www.weavers.space/stacks/foundation
Immensely capable, very well supported, steep learning curve. Stacks based on Foundation 6 from Zurb foundation.
Foundry - https://foundry.elixirgraphics.com
Has a lot of fans - well established, well supported
UI Kit - https://uikitstacks.com
Well respected with a number of die hard fans. However, I can’t get any of their sample projects to work? links do nothing?
Source - https://source.shakingthehabitual.com
Newer offering, lightweight ‘micro-framework’, inexpensive
Platform - https://platform.barth-partners.com
Newer offering, based on bulma platform
Pure - https://onelittledesigner.com/rapidweaver-theme/pure4rw/
Based on Yahoo Pure css library. Not sure how supported it is now? However 1LD are also doing:
Project Files - https://onelittledesigner.com/rapidweaver-projects/
New - described as ‘the power of a framework, for the price of a theme, in the convenience of a prebuilt RapidWeaver project file’
Freestacks - http://blueballdesign.com/rwthemes/freestack/index.html
Don’t think this is still active but may be wrong - ahead of it’s time!
Blank Theme from Will Woodgate - https://themeflood.com/blank/
Simple blank theme - use your own stacks or even built in RW pages.
Blankstrap - https://instacks.github.io/blankstrap/
Bootstrap approach from instacks