Quick updates.

Clocker/Overall App/Themer.swift

@@ -191,7 +191,7 @@ extension Themer {
     }
 
     func preferenceImage() -> NSImage {
-        if let symbolImageForPreference = symbolImage(for: "gear") {
+        if let symbolImageForPreference = symbolImage(for: "plus") {
             return symbolImageForPreference
         }
 
@@ -389,6 +389,10 @@ extension Themer {
     }
 
     func addImage() -> NSImage {
+        if let symbolImageForPreference = symbolImage(for: "plus") {
+            return symbolImageForPreference
+        }
+        
         if #available(macOS 10.14, *) {
             switch themeIndex {
             case .light, .solarizedLight:

Clocker/Preferences/General/PreferencesViewController.swift

@@ -172,8 +172,8 @@ class PreferencesViewController: ParentViewController {
 
     private func darkModeChanges() {
         if #available(macOS 10.14, *) {
-            addTimezoneButton.image = NSImage(named: .addDynamicIcon)
-            deleteButton.image = NSImage(named: NSImage.Name("Remove Dynamic"))!
+            addTimezoneButton.image = Themer.shared().addImage()
+            deleteButton.image = Themer.shared().removeImage()
         }
     }