Update application theme to use a lighter background

Adjusted CSS variables in `index.css` to change the primary background, foreground, card, popover, muted, accent, border, and input colors. Also removed the 'dark' class from the main div in `App.tsx` to revert to a light theme.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: ae4037a0-2a6f-4530-9bac-79b543286bda
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/397bca8c-984f-43ff-841a-10897aeb8140/ae4037a0-2a6f-4530-9bac-79b543286bda/gEOddVG

.replit

@@ -22,14 +22,14 @@ externalPort = 3002
 localPort = 40537
 externalPort = 3000
 
-[[ports]]
-localPort = 41095
-externalPort = 3003
-
 [[ports]]
 localPort = 43245
 externalPort = 3001
 
+[[ports]]
+localPort = 45209
+externalPort = 3003
+
 [env]
 PORT = "5000"