Fix margin issues causing patchy background within content area

Margin fixes applied:
- Remove max-width constraint (max-width: none)
- Remove auto margins (margin: 0)
- Use full viewport width (width: 100vw)
- Remove header margins that create gaps

This should eliminate margin-based gaps within the content area.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

app.py

@@ -143,15 +143,15 @@ with gr.Blocks(
         background: #fafafa !important;
     }
     .gradio-container {
-        max-width: 1200px !important;
-        margin-left: auto !important;
-        margin-right: auto !important;
+        max-width: none !important;
+        margin: 0 !important;
         background-color: #fafafa !important;
         font-family: 'Inter', 'Segoe UI', -apple-system, sans-serif !important;
+        width: 100vw !important;
     }
     .main-header {
         text-align: center;
-        margin: 2rem 0 3rem 0;
+        margin: 0 !important;
         color: #3b82f6 !important;
         font-weight: 600;
         font-size: 2.5rem;