Change white background when loading attachment to black

Tusker/Screens/Attachment/AttachmentViewController.swift

@@ -48,6 +48,9 @@ class AttachmentViewController: UIViewController {
     override func viewDidLoad() {
         super.viewDidLoad()
         
+        overrideUserInterfaceStyle = .dark
+        view.backgroundColor = .black
+        
         if let data = ImageCache.attachments.get(attachment.url) {
             createLargeImage(data: data)
         } else {

Tusker/Screens/Gallery/GalleryViewController.swift

@@ -78,6 +78,8 @@ class GalleryViewController: UIPageViewController, UIPageViewControllerDataSourc
         self.dataSource = self
         self.delegate = self
         
+        overrideUserInterfaceStyle = .dark
+
         dismissInteractionController = LargeImageInteractionController(viewController: self)
     }
 

Tusker/Screens/Utilities/LoadingViewController.swift

@@ -16,7 +16,7 @@ class LoadingViewController: UIViewController {
     override func viewDidLoad() {
         super.viewDidLoad()
         
-        view.backgroundColor = .systemBackground
+        view.backgroundColor = .clear
         
         activityIndicator = UIActivityIndicatorView(style: .large)
         activityIndicator.color = .secondaryLabel