UI Overlap Issues: Hero Section with Navbar and Chat and Mode Toggle are one on each other on mobile

**Hero Section Overlapping Navbar:**
The hero section content is appearing under the navbar, causing the top portion of the content is hidden.
**Chat and Mode Toggle Overlapping**
The chat and mode toggle buttons are positioned too close together and overlap on smaller screens.

Start at the responsive layout and styling for the hero section, navbar, chat control, and mode toggle. Reproduce the issue at a small mobile viewport, then verify that the hero content is not hidden by the navbar and that the chat and mode toggle remain separated without overlap.

Written by the indexing model from the issue text.