Make hero section text white and remove sliding arrows

Update CSS to set hero text color to white and remove carousel control buttons from index.html.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: c4caa035-0068-40f2-8dfb-9b2e79d5464e
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/8cb91fbe-a439-4e32-a1b2-170b854e4f2f/c4caa035-0068-40f2-8dfb-9b2e79d5464e/iBoGnMy
