Update header and footer colours, and skin tones.

[brunomenezes]

📄 Context

That is a one-off change in the navbar and footer that will benefit the work to be done on multiple pages.

*PS: Refer to the parent of this issue for references.

📈 Subtasks

• [x] Make sure the fonts are applied correctly based on the Figma description. i.e. Where to use each font and what size and weight to be applied.
• [x] Apply colour changes to the NavBar space where the Logo, links and wallet button lies.
• [x] Apply colour changes to the Footer space.

🎯 Definition of Done

• [x] The NavBar and Footer match the design specs.