diff --git a/flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatRootPaneUI.java b/flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatRootPaneUI.java
index 32e94c84..0e55558d 100644
--- a/flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatRootPaneUI.java
+++ b/flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatRootPaneUI.java
@@ -41,6 +41,7 @@ import javax.swing.plaf.ComponentUI;
 import javax.swing.plaf.UIResource;
 import javax.swing.plaf.basic.BasicRootPaneUI;
 import com.formdev.flatlaf.FlatClientProperties;
+import com.formdev.flatlaf.FlatLaf;
 import com.formdev.flatlaf.util.HiDPIUtils;
 import com.formdev.flatlaf.util.SystemInfo;
 
@@ -97,6 +98,13 @@ public class FlatRootPaneUI
 			if( background == null || background instanceof UIResource )
 				parent.setBackground( UIManager.getColor( "control" ) );
 		}
+
+		// enable dark window appearance on macOS when running in JetBrains Runtime
+		if( SystemInfo.IS_JETBRAINS_JVM && SystemInfo.IS_MAC_OS_10_14_MOJAVE ) {
+			LookAndFeel laf = UIManager.getLookAndFeel();
+			boolean isDark = laf instanceof FlatLaf && ((FlatLaf)laf).isDark();
+			c.putClientProperty( "jetbrains.awt.windowDarkAppearance", isDark );
+		}
 	}
 
 	private void installClientDecorations() {
diff --git a/flatlaf-core/src/main/java/com/formdev/flatlaf/util/SystemInfo.java b/flatlaf-core/src/main/java/com/formdev/flatlaf/util/SystemInfo.java
index 24a54fff..d443079d 100644
--- a/flatlaf-core/src/main/java/com/formdev/flatlaf/util/SystemInfo.java
+++ b/flatlaf-core/src/main/java/com/formdev/flatlaf/util/SystemInfo.java
@@ -34,6 +34,7 @@ public class SystemInfo
 	// OS versions
 	public static final boolean IS_WINDOWS_10_OR_LATER;
 	public static final boolean IS_MAC_OS_10_11_EL_CAPITAN_OR_LATER;
+	public static final boolean IS_MAC_OS_10_14_MOJAVE;
 	public static final boolean IS_MAC_OS_10_15_CATALINA_OR_LATER;
 
 	// Java versions
@@ -58,6 +59,7 @@ public class SystemInfo
 		long osVersion = scanVersion( System.getProperty( "os.version" ) );
 		IS_WINDOWS_10_OR_LATER = (IS_WINDOWS && osVersion >= toVersion( 10, 0, 0, 0 ));
 		IS_MAC_OS_10_11_EL_CAPITAN_OR_LATER = (IS_MAC && osVersion >= toVersion( 10, 11, 0, 0 ));
+		IS_MAC_OS_10_14_MOJAVE = (IS_MAC && osVersion >= toVersion( 10, 14, 0, 0 ));
 		IS_MAC_OS_10_15_CATALINA_OR_LATER = (IS_MAC && osVersion >= toVersion( 10, 15, 0, 0 ));
 
 		// Java versions