[511] UI-only: Adjust homepage banner height and fix style issues on mobile

[dlicheva]

Ticket
This PR adjusts the styles for the homepage and fixes a few style issues on mobile:

• make the home banner and Browse button smaller
• remove white bar on the homepage on mobile
• reduce space between the menu items on mobile
• centre the logo on mobile
• adjust the header style on tablet
• change the padding on the Explorer page to match the other pages, also tweak the search label and the sub-menu.
• align the labels on Map Analysis
• resolve a browser warning on the Map Analysis page by moving a warning message out of the table.

Homepage banner size reduction

Mobile header adjustments

Explorer page on mobile

Map Analysis page on mobile

[robvanderveer]

All magnificent