[WEBPAGE] Update style of current unicado page

Description

Reworked current webpage appearance

• Changed colorscheme to blue white
• Update landing page layout and hero section

Related Issue(s)

• N.A.

Other Changes

Screenshots/Logs

Attach screenshots or log outputs if applicable.

Testing Instructions

1. Get the merge request branch (not the origin branch)
2. run mkdocs
3. check all links and appearance

Developer Checklist

• Code has been tested locally and/or in pipeline.
• Merge conflicts resolved with the target branch.