diff --git a/com.microsoft.copilot.eclipse.ui/META-INF/MANIFEST.MF b/com.microsoft.copilot.eclipse.ui/META-INF/MANIFEST.MF
index ca0e9872..52396980 100644
--- a/com.microsoft.copilot.eclipse.ui/META-INF/MANIFEST.MF
+++ b/com.microsoft.copilot.eclipse.ui/META-INF/MANIFEST.MF
@@ -24,7 +24,8 @@ Bundle-Activator: com.microsoft.copilot.eclipse.ui.CopilotUi
 Bundle-RequiredExecutionEnvironment: JavaSE-17
 Automatic-Module-Name: com.microsoft.copilot.eclipse.ui
 Bundle-ActivationPolicy: lazy
-Import-Package: org.osgi.framework;version="[1.10.0,2.0.0)"
+Import-Package: org.eclipse.e4.ui.css.swt.theme,
+ org.osgi.framework;version="[1.10.0,2.0.0)"
 Require-Bundle: com.microsoft.copilot.eclipse.core;bundle-version="0.19.0",
  com.microsoft.copilot.eclipse.terminal.api;bundle-version="0.19.0",
  org.eclipse.ui.ide;bundle-version="3.22.0",
diff --git a/com.microsoft.copilot.eclipse.ui/src/com/microsoft/copilot/eclipse/ui/utils/UiUtils.java b/com.microsoft.copilot.eclipse.ui/src/com/microsoft/copilot/eclipse/ui/utils/UiUtils.java
index 5d1ab2a9..70544de1 100644
--- a/com.microsoft.copilot.eclipse.ui/src/com/microsoft/copilot/eclipse/ui/utils/UiUtils.java
+++ b/com.microsoft.copilot.eclipse.ui/src/com/microsoft/copilot/eclipse/ui/utils/UiUtils.java
@@ -35,7 +35,8 @@
 import org.eclipse.core.filesystem.IFileStore;
 import org.eclipse.core.resources.IFile;
 import org.eclipse.core.resources.IResource;
-import org.eclipse.core.runtime.preferences.InstanceScope;
+import org.eclipse.e4.ui.css.swt.theme.ITheme;
+import org.eclipse.e4.ui.css.swt.theme.IThemeEngine;
 import org.eclipse.e4.ui.model.application.ui.basic.MPart;
 import org.eclipse.e4.ui.services.IStylingEngine;
 import org.eclipse.e4.ui.workbench.modeling.EPartService;
@@ -88,7 +89,6 @@
 import org.eclipse.ui.part.IShowInTarget;
 import org.eclipse.ui.part.ShowInContext;
 import org.eclipse.ui.texteditor.ITextEditor;
-import org.osgi.service.prefs.Preferences;
 
 import com.microsoft.copilot.eclipse.core.CopilotCore;
 import com.microsoft.copilot.eclipse.core.utils.PlatformUtils;
@@ -505,10 +505,15 @@ public static void applyChatFont(Control control) {
    * @return true if dark theme is active, false otherwise
    */
   public static boolean isDarkTheme() {
-    Preferences preferences = InstanceScope.INSTANCE.getNode("org.eclipse.e4.ui.css.swt.theme");
-    String themeCssUri = preferences.get("themeid", "");
-    if (themeCssUri.toLowerCase().contains("dark")) {
-      return true;
+    IThemeEngine engine = PlatformUI.getWorkbench().getService(IThemeEngine.class);
+    if (engine != null) {
+      ITheme activeTheme = engine.getActiveTheme();
+      if (activeTheme != null) {
+        String themeCssUri = activeTheme.getId();
+        if (themeCssUri != null && themeCssUri.toLowerCase().contains("dark")) {
+          return true;
+        }
+      }
     }
     return false;
   }