Minor adjustments to styles

- Removes line of text from sectors viz on homepage to clarify
- Changes color of bar chart illustrations on sectors page to improve contrast
- Removes same color changes from `ol`
- Changes base link styles: adds underline to add a non-color link indication; brightens default color; make hover and focus color more obvious (instead of darker blue goes to red); removes underline on hover now that we have it for all links
- Cleans padding and alignment on official usa site bug