Visual identity
Do we keep Bootstrap with Vue 3 or do we replace it with VueFomanticUI (when Fomantic-UI version 3.0 will be available), Element Plus, Naive UI, other?
Element+ plans themes for A11Y.
TODO 1: add a dark theme and a theme for color blind users. The choice of the theme must be made by each user -> move theme choice from Settings - Feature to Settings - Users.
Actual colors (Bootstrap): see client/src/assets/stylus/variables.styl