Todos:
- info popups
- custom breathing exercises
- dark mode
- formalise imports
- make prettier & eslint better
- tests
- hold countdown animation
- intro animation
- get first name from localstorage?
- intro image
- countdown before exercise starts
- badge select animation
- instructions
- breathing page redesign
- time of day greeting
- buzz for exercise intervals
- breathing times, EG 4, 4, 4, 4