Fallback values for variables

[ineagu]

Description:

Right now we are not using fallback values for variables ( fonts, colors etc), fallbacks should help when the variable does not exist anymore, either the user somehow delete them or our theme is deactivated.

User story:

Find a way to use switch, deactivate, delete theme hooks to inject the variables into the created pages. Leverage Otter as a fallback, like otter in otter css can define the neve pallete variables as a sort of fallback

cc @selul

[ineagu]

Another thought here since we are working to redo the demos, maybe we can make sure we do have this for new demos, fallback values.