diff --git a/Pdf4QtDiff/main.cpp b/Pdf4QtDiff/main.cpp
index 2110a20..8d1dd23 100644
--- a/Pdf4QtDiff/main.cpp
+++ b/Pdf4QtDiff/main.cpp
@@ -24,6 +24,7 @@
 #include "pdfdocumentreader.h"
 #include "pdfsecurityhandler.h"
 #include "pdfapplicationtranslator.h"
+#include "pdfwidgetutils.h"
 #include "mainwindow.h"
 
 #include <QApplication>
@@ -40,10 +41,14 @@ int main(int argc, char *argv[])
     QApplication::setApplicationDisplayName(QApplication::translate("Application", "PDF4QT Diff"));
 
     QCommandLineOption noDrm("no-drm", "Disable DRM settings of documents.");
+    QCommandLineOption lightGui("theme-light", "Use a light theme for the GUI.");
+    QCommandLineOption darkGui("theme-dark", "Use a dark theme for the GUI.");
 
     QCommandLineParser parser;
     parser.setApplicationDescription(QCoreApplication::applicationName());
     parser.addOption(noDrm);
+    parser.addOption(lightGui);
+    parser.addOption(darkGui);
     parser.addHelpOption();
     parser.addVersionOption();
     parser.addPositionalArgument("file1", "The PDF file to be compared.");
@@ -55,6 +60,8 @@ int main(int argc, char *argv[])
         pdf::PDFSecurityHandler::setNoDRMMode();
     }
 
+    pdf::PDFWidgetUtils::setDarkTheme(parser.isSet(lightGui), parser.isSet(darkGui));
+
     pdf::PDFApplicationTranslator translator;
     translator.installTranslator();
 
diff --git a/Pdf4QtLibWidgets/sources/pdfdrawspacecontroller.cpp b/Pdf4QtLibWidgets/sources/pdfdrawspacecontroller.cpp
index 16ba44e..c5bc157 100644
--- a/Pdf4QtLibWidgets/sources/pdfdrawspacecontroller.cpp
+++ b/Pdf4QtLibWidgets/sources/pdfdrawspacecontroller.cpp
@@ -30,6 +30,7 @@
 #include "pdfdrawwidget.h"
 #include "pdfwidgetannotation.h"
 #include "pdfpainterutils.h"
+#include "pdfwidgetutils.h"
 
 #include <QTimer>
 #include <QPainter>
@@ -785,7 +786,10 @@ QColor PDFDrawWidgetProxy::getPaperColor()
 
 void PDFDrawWidgetProxy::drawPages(QPainter* painter, QRect rect, PDFRenderer::Features features)
 {
-    painter->fillRect(rect, Qt::lightGray);
+    const bool darkScheme = PDFWidgetUtils::isDarkTheme();
+    QColor backgroundColor = darkScheme ? QColor(34, 34, 34) : QColor(Qt::lightGray);
+
+    painter->fillRect(rect, backgroundColor);
     QTransform baseMatrix = painter->worldTransform();
 
     // Use current paper color (it can be a bit different from white)
diff --git a/Pdf4QtLibWidgets/sources/pdfwidgetutils.cpp b/Pdf4QtLibWidgets/sources/pdfwidgetutils.cpp
index b8e6ee5..8a7e990 100644
--- a/Pdf4QtLibWidgets/sources/pdfwidgetutils.cpp
+++ b/Pdf4QtLibWidgets/sources/pdfwidgetutils.cpp
@@ -196,11 +196,10 @@ void PDFWidgetUtils::setDarkTheme(bool isLightTheme, bool isDarkTheme)
     {
         QPalette darkPalette = QApplication::palette();
 
-#ifdef Q_OS_WIN
         QApplication::setStyle(QStyleFactory::create("Fusion"));
 
         // Basic colors
-        darkPalette.setColor(QPalette::WindowText, QColor(220, 220, 220));
+        darkPalette.setColor(QPalette::WindowText, QColor(240, 246, 252));
         darkPalette.setColor(QPalette::Button, QColor(53, 53, 53));
         darkPalette.setColor(QPalette::Light, QColor(70, 70, 70));
         darkPalette.setColor(QPalette::Midlight, QColor(60, 60, 60));
@@ -213,8 +212,8 @@ void PDFWidgetUtils::setDarkTheme(bool isLightTheme, bool isDarkTheme)
         darkPalette.setColor(QPalette::ButtonText, QColor(220, 220, 220));
 
         // Background
-        darkPalette.setColor(QPalette::Base, QColor(42, 42, 42));
-        darkPalette.setColor(QPalette::Window, QColor(53, 53, 53));
+        darkPalette.setColor(QPalette::Base, QColor(13, 17, 23));
+        darkPalette.setColor(QPalette::Window, QColor(1, 4, 9));
         darkPalette.setColor(QPalette::Shadow, QColor(20, 20, 20));
 
         // Highlight
@@ -245,7 +244,6 @@ void PDFWidgetUtils::setDarkTheme(bool isLightTheme, bool isDarkTheme)
             currentColor = currentColor.lighter(150);
             darkPalette.setColor(QPalette::Current, static_cast<QPalette::ColorRole>(i), currentColor);
         }
-#endif
 
         // Placeholder text (Qt 5.12+)
         darkPalette.setColor(QPalette::PlaceholderText, QColor(150, 150, 150));