Update color palette and styles across components for improved visual consistency

- Changed theme color in index.html to a brighter orange for better aesthetics.
- Introduced a modern color palette in styles.scss for enhanced readability and consistency.
- Updated various components (AppFooter, AppNavigation, DialogWidget, etc.) to utilize new color variables, ensuring a cohesive look throughout the application.
- Adjusted button styles and hover effects for improved user interaction feedback.
- Enhanced background colors and text colors for better contrast and visibility.

frontend/src/components/SettingsWidget.vue

@@ -253,9 +253,9 @@ export default {
         margin-left: 10px;
         padding: 5px 12px;
         cursor: pointer;
-        background: #F9A22C;
+        background: #FF6B35;
         color: #000000;
-        border: 1px solid #F9A22C;
+        border: 1px solid #FF6B35;
         border-radius: 4px;
         transition: background 0.05s;
         border: 1px solid transparent;
@@ -263,8 +263,8 @@ export default {
     }
     
     .contact-button:hover {
-        background: #fdf1db;
-        color: #7E471B;
-        border: 1px solid #7E471B;
+        background: #FFF4F0;
+        color: #5D4037;
+        border: 1px solid #5D4037;
     }
 </style>