Make sure SCSS works correctly

[xvaara]

• [ ] check that we don't use scoped styles anywere
  • [ ] BModal has scoped
  • [ ] BFormFile has scoped
  • [ ] BAlert has scoped
• [ ] Re-evaluate the need for all the scss in components
• [ ] Make sure we use variables everywhere
• [ ] Make docs on how to use scss
• [ ] BOverlay (used in modal) doesn't use bootstrap backdrop styles