## Complete Multi-language System & Navigation Enhancement

### Features Added:
- **Multi-language Support**: Dutch/English with URL-based switching (?lang=nl|en)
- **Theme Customization**: Configurable header/navigation colors via config.json
- **Navigation Improvements**: Active states, dropdown chevron icons, visual distinction
- **Mobile Responsive**: Separate desktop/mobile search layouts
- **Template System**: Fixed rendering pipeline for all partials

### Technical Fixes:
- Fixed language file path (engine/lang/ vs engine/core/class/../lang/)
- Added template data rendering to layout template
- Implemented navigation active state for default/home page
- Added chevron icons to dropdown folders for visual distinction
- Removed hardcoded navigation opacity class for theme colors

### Files Modified:
- config.json: Added theme and language configuration
- engine/core/class/CodePressCMS.php: Multi-language and navigation logic
- engine/templates/: Enhanced header, footer, navigation, layout
- engine/lang/: Dutch and English translation files
- public/assets/css/mobile.css: Mobile responsive fixes

### Result:
Fully functional multi-language CMS with proper navigation states and theme customization.

public/assets/css/mobile.css

@@ -0,0 +1,54 @@
+/* Mobile search improvements */
+@media (max-width: 991.98px) {
+    .navbar {
+        position: relative;
+    }
+    
+    /* Hide desktop elements on mobile */
+    .d-none.d-lg-flex {
+        display: none !important;
+    }
+    
+    #mobileSearch {
+        position: absolute;
+        top: 100%;
+        left: 0;
+        right: 0;
+        background: var(--header-bg);
+        z-index: 1030;
+    }
+    
+    #mobileSearch.show {
+        box-shadow: 0 4px 6px rgba(0,0,0,0.1);
+    }
+    
+    /* Ensure navigation doesn't overlap with expanded search */
+    .navigation-section {
+        margin-top: 0;
+        border: none !important;
+    }
+}
+
+/* Desktop improvements */
+@media (min-width: 992px) {
+    /* Hide mobile elements on desktop */
+    .d-lg-none {
+        display: none !important;
+    }
+    
+    /* Hide mobile search on desktop */
+    #mobileSearch {
+        display: none !important;
+    }
+}
+
+/* Search form improvements */
+.form-control[type="search"] {
+    min-width: 200px;
+}
+
+@media (max-width: 576px) {
+    .form-control[type="search"] {
+        min-width: 150px;
+    }
+}