fix: update heroBanner background gradient for improved styling

Author: mhnpd

docs/src/pages/index.module.css

@@ -4,7 +4,7 @@
  */
 
 .heroBanner {
-  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
+  background: linear-gradient(135deg, #2e8555 0%, #25c2a0 100%);
   padding: 6rem 0;
   text-align: center;
   position: relative;