Refactor App component styles and remove highlights section

- Updated background gradient colors for a lighter theme.
- Changed button styles to improve visibility.
- Removed the highlights section to streamline the layout.
- Adjusted text colors for better contrast and readability.

src/routes/__root.tsx

@@ -14,7 +14,7 @@ export const Route = createRootRouteWithContext<AuthContext>()({
       <ThemeProvider defaultTheme="light" storageKey="vite-ui-theme">
 
         <Outlet />
-        <TanstackDevtools
+{/*         <TanstackDevtools
           config={{
             position: 'bottom-left',
           }}
@@ -24,7 +24,7 @@ export const Route = createRootRouteWithContext<AuthContext>()({
               render: <TanStackRouterDevtoolsPanel />,
             },
           ]}
-        />
+        /> */}
       </ThemeProvider>
     </>
   ),