diff --git a/CMakeLists.txt b/CMakeLists.txt
index dd63cbc1797fe9777bd30a8a6d4308de0cd8f693..6563bc457e9ff2c5d18937a6e64cab3b51c38119 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -32,7 +32,7 @@ configure_file(src/environments.h.in environments.h @ONLY)
 file(GLOB SRCS "src/*.h" "src/*.cpp"
                "src/thememodule/*.h" "src/thememodule/*.cpp"
                "src/widgets/*.h" "src/widgets/*.cpp"
-               "src/wayland/kywc-toplevel-v1-protocol.c" 
+               "src/wayland/kywc-toplevel-v1-protocol.c"
                "src/wayland/*.cpp" "src/wayland/*.h")
 
 # Find the library
@@ -45,29 +45,30 @@ find_package(Qt6Concurrent REQUIRED)
 find_package(Qt6PrintSupport REQUIRED)
 find_package(Qt6Gui REQUIRED)
 find_package(Qt6WaylandClient REQUIRED)
-find_package(Dtk2widget REQUIRED)
+find_package(Dtk6Widget REQUIRED)
 find_package(Dtk6Core REQUIRED)
 find_package(KF6SyntaxHighlighting REQUIRED)
 find_package(KF6Codecs REQUIRED)
 
 # 尝试查找WebEngine模块
-find_package(Qt6WebEngine QUIET)
+find_package(Qt6WebEngineCore QUIET)
 find_package(Qt6WebEngineWidgets QUIET)
+find_package(Qt6WebChannel QUIET)
 
 include_directories(${Qt6Gui_PRIVATE_INCLUDE_DIRS})
 
 # Tell CMake to create the executable
 add_executable(gxde-editor ${SRCS} src/gxde-editor.qrc)
-target_include_directories(gxde-editor PUBLIC 
-    /usr/include/dtk2/DWidget 
-    /usr/include/dtk6/DCore 
-    /usr/include/dtk6/DLog 
+target_include_directories(gxde-editor PUBLIC
+    /usr/include/dtk6/DWidget
+    /usr/include/dtk6/DCore
+    /usr/include/dtk6/DLog
     /usr/include/dtk6/DGui
-    ${OBJECT_BINARY_DIR} 
+    ${OBJECT_BINARY_DIR}
     ${CMARK_INCLUDE_DIRS}
 )
 target_link_libraries(gxde-editor
-    ${Dtk2widget_LIBRARIES}
+    Dtk6::Widget
     Dtk6::Core
     Qt6::Widgets
     Qt6::DBus
@@ -83,11 +84,12 @@ target_link_libraries(gxde-editor
 )
 
 # 判断 Qt6WebEngine 模块是否存在
-if(Qt6WebEngine_FOUND AND Qt6WebEngineWidgets_FOUND)
+if(Qt6WebEngineCore_FOUND AND Qt6WebEngineWidgets_FOUND AND Qt6WebChannel_FOUND)
     # 添加模块链接和宏定义
     target_link_libraries(gxde-editor
-        Qt6::WebEngine
+        Qt6::WebEngineCore
         Qt6::WebEngineWidgets
+        Qt6::WebChannel
     )
     target_compile_definitions(gxde-editor
         PRIVATE
diff --git a/debian/control b/debian/control
index 6fc596a98d1edbfe476c152ca2b729b9c708e663..abc1d837c8b135a4b8d156f33c07b93025767f91 100644
--- a/debian/control
+++ b/debian/control
@@ -4,19 +4,19 @@ Priority: optional
 Maintainer: gfdgd xi <3025613752@qq.com>, Deepin Packages Builder <packages@linuxdeepin.com>
 Build-Depends:
  debhelper (>= 9),
- cmake, 
+ cmake,
  pkg-config,
- libdtk6core-dev, 
- libdtk2widget6-dev, 
- qt6-base-dev, 
- libpolkit-qt6-1-dev, 
- libkf6syntaxhighlighting-dev, 
- libkf6codecs-dev, 
+ libdtk6core-dev,
+ libdtk6widget-dev,
+ qt6-base-dev,
+ libpolkit-qt6-1-dev,
+ libkf6syntaxhighlighting-dev,
+ libkf6codecs-dev,
  qt6-tools-dev-tools,
  qt6-base-private-dev,
  qt6-5compat-dev,
- qt6-wayland-dev
-# qt6-webengine-dev [i386 amd64 armhf arm64 mips64el loong64]
+ qt6-wayland-dev,
+ qt6-webengine-dev,
 Standards-Version: 3.9.8
 Homepage: https://www.gxde.top
 
diff --git a/src/editwrapper.cpp b/src/editwrapper.cpp
index e73a12a58136f7508377e2e9a14aac02a15719b5..58a0248565645c0359254bdedcfe97564be98745 100644
--- a/src/editwrapper.cpp
+++ b/src/editwrapper.cpp
@@ -35,6 +35,7 @@
 #include <QDebug>
 #include <QTimer>
 #include <QDir>
+#include <DGuiApplicationHelper>
 
 #include "drecentmanager.h"
 
@@ -101,7 +102,7 @@ EditWrapper::EditWrapper(QWidget *parent)
     connect(m_toast, &Toast::saveAsBtnClicked, this, &EditWrapper::requestSaveAs);
     connect(m_pendingLoadTimer, &QTimer::timeout, this, &EditWrapper::appendPendingTextLoadChunk);
 
-    setDarkTheme(DThemeManager::instance()->theme() == "dark");
+    setDarkTheme(Dtk::Gui::DGuiApplicationHelper::instance()->themeType() == Dtk::Gui::DGuiApplicationHelper::DarkType);
 }
 
 EditWrapper::~EditWrapper()
diff --git a/src/findbar.cpp b/src/findbar.cpp
index 83e7cef0698ee38d085f73b2227dec0fe71710d3..a542e8105d21b2d0a344308a745f44a589550b51 100644
--- a/src/findbar.cpp
+++ b/src/findbar.cpp
@@ -25,6 +25,7 @@
 
 #include <QPainterPath>
 #include <QDebug>
+#include <QIcon>
 
 FindBar::FindBar(QWidget *parent)
     : QWidget(parent)
@@ -39,7 +40,7 @@ FindBar::FindBar(QWidget *parent)
     m_editLine = new LineBar();
     m_findNextButton = new QPushButton(tr("Next"));
     m_findPrevButton = new QPushButton(tr("Previous"));
-    m_closeButton = new DImageButton();
+    m_closeButton = new QPushButton();
     m_closeButton->setFixedSize(16, 16);
 
     m_layout->addWidget(m_findLabel);
@@ -61,7 +62,7 @@ FindBar::FindBar(QWidget *parent)
     connect(m_findNextButton, &QPushButton::clicked, this, &FindBar::findNext, Qt::QueuedConnection);
     connect(m_findPrevButton, &QPushButton::clicked, this, &FindBar::findPrev, Qt::QueuedConnection);
 
-    connect(m_closeButton, &DImageButton::clicked, this, &FindBar::findCancel, Qt::QueuedConnection);
+    connect(m_closeButton, &QPushButton::clicked, this, &FindBar::findCancel, Qt::QueuedConnection);
 }
 
 bool FindBar::isFocus()
@@ -72,15 +73,15 @@ bool FindBar::isFocus()
 void FindBar::focus()
 {
     m_editLine->setFocus();
-    m_editLine->selectAll();
+    m_editLine->lineEdit()->selectAll();
 }
 
 void FindBar::activeInput(QString text, QString file, int row, int column, int scrollOffset)
 {
     // Try fill keyword with select text.
     m_editLine->clear();
-    m_editLine->insert(text);
-    m_editLine->selectAll();
+    m_editLine->lineEdit()->insert(text);
+    m_editLine->lineEdit()->selectAll();
 
     // Show.
     QWidget::show();
@@ -143,15 +144,13 @@ void FindBar::setBackground(QString color)
     if (QColor(m_backgroundColor).lightness() < 128) {
         m_findLabel->setStyleSheet(QString("QLabel { background-color: %1; color: %2; }").arg(color).arg("#AAAAAA"));
 
-        m_closeButton->setNormalPic(Utils::getQrcPath("bar_close_normal_dark.svg"));
-        m_closeButton->setHoverPic(Utils::getQrcPath("bar_close_hover_dark.svg"));
-        m_closeButton->setPressPic(Utils::getQrcPath("bar_close_press_dark.svg"));
+        m_closeButton->setIcon(QIcon(Utils::getQrcPath("bar_close_normal_dark.svg")));
+        m_closeButton->setStyleSheet("QPushButton { border: none; }");
     } else {
         m_findLabel->setStyleSheet(QString("QLabel { background-color: %1; color: %2; }").arg(color).arg("#000000"));
 
-        m_closeButton->setNormalPic(Utils::getQrcPath("bar_close_normal_light.svg"));
-        m_closeButton->setHoverPic(Utils::getQrcPath("bar_close_hover_light.svg"));
-        m_closeButton->setPressPic(Utils::getQrcPath("bar_close_press_light.svg"));
+        m_closeButton->setIcon(QIcon(Utils::getQrcPath("bar_close_normal_light.svg")));
+        m_closeButton->setStyleSheet("QPushButton { border: none; }");
     }
 
     update();
diff --git a/src/findbar.h b/src/findbar.h
index ae0bd7ef043cc213766f591eedf52ec2aebe6ea9..b2d39f81f23a191408395d2ad151468f80ae40de 100644
--- a/src/findbar.h
+++ b/src/findbar.h
@@ -30,7 +30,7 @@
 #include <QLabel>
 #include <QPainter>
 #include <QWidget>
-#include <dimagebutton.h>
+#include <QPushButton>
 
 DWIDGET_USE_NAMESPACE
 
@@ -67,7 +67,7 @@ protected:
 private:
     QPushButton *m_findNextButton;
     QPushButton *m_findPrevButton;
-    DImageButton *m_closeButton;
+    QPushButton *m_closeButton;
     LineBar *m_editLine;
     QHBoxLayout *m_layout;
     QLabel *m_findLabel;
diff --git a/src/jumplinebar.cpp b/src/jumplinebar.cpp
index a5eb7cd7ffb6f545712c6000c7745bd9c2a1eca8..d9b94ccbac1432a89a63f661e94c212d0c3a7c41 100644
--- a/src/jumplinebar.cpp
+++ b/src/jumplinebar.cpp
@@ -41,7 +41,7 @@ JumpLineBar::JumpLineBar(QWidget *parent)
     m_editLine = new LineBar();
 
     m_lineValidator = new QIntValidator;
-    m_editLine->setValidator(m_lineValidator);
+    m_editLine->lineEdit()->setValidator(m_lineValidator);
 
     m_layout->addWidget(m_label);
     m_layout->addWidget(m_editLine);
diff --git a/src/main.cpp b/src/main.cpp
index 70e73e6841e10c0223f8af8dfd1b7e16ac5a925b..79625939120b91b5206eef2c2f6a9831d030ffa5 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -44,8 +44,6 @@ DTK_USE_NAMESPACE
 
 int main(int argc, char *argv[])
 {
-    // Init DTK.
-    DApplication::loadDXcbPlugin();
 
     const char *descriptionText = QT_TRANSLATE_NOOP("MainWindow",
                                                     "GXDE Editor is a desktop text editor that supports common text editing features.");
diff --git a/src/replacebar.cpp b/src/replacebar.cpp
index bec03fc067744e6b1910d768b5536cd6b59006f1..f96f044686de56e583d2926d97b642a7fbcba415 100644
--- a/src/replacebar.cpp
+++ b/src/replacebar.cpp
@@ -25,6 +25,7 @@
 
 #include <QPainterPath>
 #include <QDebug>
+#include <QIcon>
 
 ReplaceBar::ReplaceBar(QWidget *parent)
     : QWidget(parent)
@@ -43,7 +44,7 @@ ReplaceBar::ReplaceBar(QWidget *parent)
     m_replaceSkipButton = new QPushButton(tr("Skip"));
     m_replaceRestButton = new QPushButton(tr("Replace Rest"));
     m_replaceAllButton = new QPushButton(tr("Replace All"));
-    m_closeButton = new DImageButton();
+    m_closeButton = new QPushButton();
     m_closeButton->setFixedSize(16, 16);
 
     m_layout->addWidget(m_replaceLabel);
@@ -85,7 +86,7 @@ ReplaceBar::ReplaceBar(QWidget *parent)
     connect(m_replaceRestButton, &QPushButton::clicked, this, &ReplaceBar::handleReplaceRest, Qt::QueuedConnection);
     connect(m_replaceAllButton, &QPushButton::clicked, this, &ReplaceBar::handleReplaceAll, Qt::QueuedConnection);
 
-    connect(m_closeButton, &DImageButton::clicked, this, &ReplaceBar::replaceCancel, Qt::QueuedConnection);
+    connect(m_closeButton, &QPushButton::clicked, this, &ReplaceBar::replaceCancel, Qt::QueuedConnection);
 }
 
 bool ReplaceBar::isFocus()
@@ -102,8 +103,8 @@ void ReplaceBar::activeInput(QString text, QString file, int row, int column, in
 {
     // Try fill keyword with select text.
     m_replaceLine->clear();
-    m_replaceLine->insert(text);
-    m_replaceLine->selectAll();
+    m_replaceLine->lineEdit()->insert(text);
+    m_replaceLine->lineEdit()->selectAll();
 
     // Show.
     show();
@@ -176,16 +177,14 @@ void ReplaceBar::setBackground(QString color)
         m_replaceLabel->setStyleSheet(QString("QLabel { background-color: %1; color: %2; }").arg(color).arg("#AAAAAA"));
         m_withLabel->setStyleSheet(QString("QLabel { background-color: %1; color: %2; }").arg(color).arg("#AAAAAA"));
 
-        m_closeButton->setNormalPic(Utils::getQrcPath("bar_close_normal_dark.svg"));
-        m_closeButton->setHoverPic(Utils::getQrcPath("bar_close_hover_dark.svg"));
-        m_closeButton->setPressPic(Utils::getQrcPath("bar_close_press_dark.svg"));
+        m_closeButton->setIcon(QIcon(Utils::getQrcPath("bar_close_normal_dark.svg")));
+        m_closeButton->setStyleSheet("QPushButton { border: none; }");
     } else {
         m_replaceLabel->setStyleSheet(QString("QLabel { background-color: %1; color: %2; }").arg(color).arg("#000000"));
         m_withLabel->setStyleSheet(QString("QLabel { background-color: %1; color: %2; }").arg(color).arg("#000000"));
 
-        m_closeButton->setNormalPic(Utils::getQrcPath("bar_close_normal_light.svg"));
-        m_closeButton->setHoverPic(Utils::getQrcPath("bar_close_hover_light.svg"));
-        m_closeButton->setPressPic(Utils::getQrcPath("bar_close_press_light.svg"));
+        m_closeButton->setIcon(QIcon(Utils::getQrcPath("bar_close_normal_light.svg")));
+        m_closeButton->setStyleSheet("QPushButton { border: none; }");
     }
 
     repaint();
diff --git a/src/replacebar.h b/src/replacebar.h
index 32c17ff43de5efa6765714354a1e69a3206b42cb..2c63c03baaac439dea67ab5448eccd1beed3aaa0 100644
--- a/src/replacebar.h
+++ b/src/replacebar.h
@@ -30,7 +30,7 @@
 #include <QLabel>
 #include <QPainter>
 #include <QWidget>
-#include <dimagebutton.h>
+#include <QPushButton>
 
 DWIDGET_USE_NAMESPACE
 
@@ -77,7 +77,7 @@ private:
     QPushButton *m_replaceButton;
     QPushButton *m_replaceRestButton;
     QPushButton *m_replaceSkipButton;
-    DImageButton *m_closeButton;
+    QPushButton *m_closeButton;
     LineBar *m_replaceLine;
     LineBar *m_withLine;
     QHBoxLayout *m_layout;
diff --git a/src/settings.cpp b/src/settings.cpp
index 2cbb2d641d88684816b5f22bbe4c22210f47dc84..842deb5a605a2ea2010a5347b14285a6bc90ad8c 100644
--- a/src/settings.cpp
+++ b/src/settings.cpp
@@ -32,6 +32,7 @@
 #include <QFontDatabase>
 #include <QApplication>
 #include <QComboBox>
+#include <QHBoxLayout>
 #include <QDebug>
 #include <QDir>
 #include <QStandardPaths>
@@ -144,7 +145,13 @@ QWidget *Settings::createFontComBoBoxHandle(QObject *obj)
     auto option = qobject_cast<DTK_CORE_NAMESPACE::DSettingsOption *>(obj);
 
     QComboBox *comboBox = new QComboBox;
-    QWidget *optionWidget = DSettingsWidgetFactory::createTwoColumWidget(option, comboBox);
+    const auto pair = DSettingsWidgetFactory::createStandardItem(QByteArray(), option, comboBox);
+    QWidget *optionWidget = new QWidget;
+    QHBoxLayout *layout = new QHBoxLayout(optionWidget);
+    layout->setContentsMargins(0, 0, 0, 0);
+    layout->setSpacing(0);
+    layout->addWidget(pair.first);
+    layout->addWidget(pair.second);
 
     QFontDatabase fontDatabase;
     comboBox->addItems(fontDatabase.families());
diff --git a/src/widgets/bottombar.cpp b/src/widgets/bottombar.cpp
index 66600b6313cd1663fd3e6488d19ec9d6c00b7a6a..df13d220bafc7ebbb99ac0f72cb15eaaef2fd72d 100644
--- a/src/widgets/bottombar.cpp
+++ b/src/widgets/bottombar.cpp
@@ -22,6 +22,7 @@
 #include "../editwrapper.h"
 #include <QLabel>
 #include <QPainter>
+#include <QPainterPath>
 #include <QHBoxLayout>
 #include <QMenu>
 
diff --git a/src/widgets/markdownpreviewwidget.cpp b/src/widgets/markdownpreviewwidget.cpp
index 5ea6b6c1ef664c2f6b7381d450f948aaab8beac3..f27d9cefec8284543c5ca72bb4a789fd1351c624 100644
--- a/src/widgets/markdownpreviewwidget.cpp
+++ b/src/widgets/markdownpreviewwidget.cpp
@@ -4,15 +4,13 @@
 #include <QScrollBar>
 #include <QFile>
 #include <QWebEngineSettings>
+#include <QUrl>
 #include <QJsonDocument>
-#include <QWebEngineScript>
-#include <QWebEngineScriptCollection>
 #include <QJsonValue>
 #include <QJsonObject>
 #include <QJsonArray>
-
-#include <QDBusMessage>
-#include <QDBusConnection>
+#include <QtMath>
+#include <QWebChannel>
 
 // 使用GitHub风格的Markdown样式
 const QString STYLE_LIGHT = R"(
@@ -43,19 +41,18 @@ const QString STYLE_DARK = R"(
   </style>
 )";
 
-// JavaScript 同步代码
-const QString SCROLL_SYNC_JS = R"(
-let lastSentPosition = 0;
-const SYNC_THRESHOLD = 5; // 像素阈值避免微小抖动
+MarkdownPreviewBridge::MarkdownPreviewBridge(MarkdownPreviewWidget* widget)
+    : QObject(widget)
+    , m_widget(widget)
+{
+}
 
-window.addEventListener('scroll', function(e) {
-    const current = window.scrollY || document.documentElement.scrollTop;
-    if (Math.abs(current - lastSentPosition) > SYNC_THRESHOLD) {
-        lastSentPosition = current;
-        window.external.syncPreviewScroll(current);
+void MarkdownPreviewBridge::syncPreviewToEditor(double ratio)
+{
+    if (m_widget) {
+        m_widget->syncPreviewToEditor(ratio);
     }
-});
-)";
+}
 
 MarkdownPreviewWidget::MarkdownPreviewWidget(QWidget* parent)
     : QWidget(parent)
@@ -65,6 +62,10 @@ MarkdownPreviewWidget::MarkdownPreviewWidget(QWidget* parent)
 
     m_webView = new QWebEngineView(this);
     m_webPage = new MarkdownWebPage(this);
+    m_webChannel = new QWebChannel(this);
+    m_bridge = new MarkdownPreviewBridge(this);
+    m_webChannel->registerObject(QStringLiteral("markdownPreview"), m_bridge);
+    m_webPage->setWebChannel(m_webChannel);
 
     m_webView->setPage(m_webPage);
     m_webView->settings()->setAttribute(QWebEngineSettings::WebAttribute::LocalContentCanAccessRemoteUrls, true);
@@ -78,132 +79,177 @@ MarkdownPreviewWidget::MarkdownPreviewWidget(QWidget* parent)
     m_updateTimer->setSingleShot(true);
     connect(m_updateTimer, &QTimer::timeout, this, &MarkdownPreviewWidget::performUpdate);
 
+    // 定时轮询预览区滚动位置，用于预览 -> 编辑器的同步
     m_scrollSyncTimer = new QTimer(this);
-    m_scrollSyncTimer->setSingleShot(true);
-    //connect(m_scrollSyncTimer, &QTimer::timeout, this, &MarkdownPreviewWidget::setupScrollSync);
+    m_scrollSyncTimer->setInterval(50);
+    connect(m_scrollSyncTimer, &QTimer::timeout, this, &MarkdownPreviewWidget::pollPreviewScroll);
+
+    // 页面加载完成后恢复滚动比例并开始监听预览区滚动
+    connect(m_webView, &QWebEngineView::loadFinished,
+            this, &MarkdownPreviewWidget::onPreviewLoadFinished);
 }
 
 bool MarkdownPreviewWidget::isSupport()
 {
-    // 检测是否是 root 用户且有设置 QTWEBENGINE_DISABLE_SANDBOX
-    if (QProcessEnvironment::systemEnvironment().value("USER") != "root" ||
-        QProcessEnvironment::systemEnvironment().value("QTWEBENGINE_DISABLE_SANDBOX") == "1") {
-        QDBusMessage dbus = QDBusMessage::createMethodCall("com.gxde.daemon.system.info",
-                                                           "/com/gxde/daemon/system/info",
-                                                           "com.gxde.daemon.system.info",
-                                                           "IsInChroot");
-        auto result = QDBusConnection::sessionBus().call(dbus);
-        bool isInChroot = false;
-        if (result.arguments().count() > 0) {
-            isInChroot = result.arguments().at(0).toBool();
-        }
-        if (!isInChroot) {
-            return 1;
-        }
-    }
-    return 0;
+    // 只要编译期启用了 WebEngine，就启用 Markdown 预览。
+    // 之前还会根据 root/chroot 环境禁用，导致部分环境下看不到预览界面。
+    return true;
 }
 
-void MarkdownPreviewWidget::setSourceEditor(QTextEdit* editor) {
-    if (m_sourceEditor == editor) return;
+void MarkdownPreviewWidget::setSourceEditor(QTextEdit* editor)
+{
+    if (m_sourceEditor == editor)
+        return;
 
     if (m_sourceEditor) {
         disconnect(m_sourceEditor, &QTextEdit::textChanged,
                    this, &MarkdownPreviewWidget::scheduleUpdate);
-    }
-
-    if (m_sourceEditor) {
         disconnect(m_sourceEditor->verticalScrollBar(), &QScrollBar::valueChanged,
-            this, &MarkdownPreviewWidget::syncEditorToPreview);
+                   this, &MarkdownPreviewWidget::syncEditorToPreview);
     }
 
     m_sourceEditor = editor;
+    ++m_loadGeneration;
+    m_syncing = false;
+    m_lastScrollRatio = 0.0;
+    m_lastPreviewRatio = 0.0;
 
-    if (m_sourceEditor) {
-        connect(m_sourceEditor, &QTextEdit::textChanged,
-                this, &MarkdownPreviewWidget::scheduleUpdate);
-        scheduleUpdate();
-    }
+    if (m_scrollSyncTimer)
+        m_scrollSyncTimer->stop();
 
-    // 初始化滚动同步
-    if (m_sourceEditor) {
-        connect(m_sourceEditor->verticalScrollBar(), &QScrollBar::valueChanged,
-                this, &MarkdownPreviewWidget::syncEditorToPreview);
-        // 初始化内容
-        m_webView->setHtml(generateHtml(m_sourceEditor->toPlainText()));
+    if (!m_sourceEditor) {
+        m_webView->setHtml(QString());
+        return;
     }
-}
 
-void MarkdownPreviewWidget::setupScrollSync() {
-    // 注入JavaScript同步处理器
-    QWebEngineScript script;
-    script.setSourceCode(SCROLL_SYNC_JS);
-    script.setName("ScrollSync");
-    script.setWorldId(QWebEngineScript::MainWorld);
-    script.setInjectionPoint(QWebEngineScript::DocumentReady);
-    m_webView->page()->scripts().insert(script);
+    connect(m_sourceEditor, &QTextEdit::textChanged,
+            this, &MarkdownPreviewWidget::scheduleUpdate);
+    connect(m_sourceEditor->verticalScrollBar(), &QScrollBar::valueChanged,
+            this, &MarkdownPreviewWidget::syncEditorToPreview);
+
+    // 初始化内容，页面加载完成后会恢复滚动位置
+    m_webView->setHtml(generateHtml(m_sourceEditor->toPlainText()), QUrl("qrc:/"));
 }
 
-double MarkdownPreviewWidget::calculateSyncRatio() {
-    const int editorHeight = m_sourceEditor->height();
-    const int editorContentHeight = m_sourceEditor->document()->size().height();
-    const double editorVisibleRatio = static_cast<double>(editorHeight) / editorContentHeight;
+void MarkdownPreviewWidget::syncEditorToPreview()
+{
+    if (!m_sourceEditor || m_syncing)
+        return;
 
-    // 获取预览内容高度
-    int previewContentHeight = 0;
-    m_webView->page()->runJavaScript("document.documentElement.scrollHeight",
-        [&](const QVariant& result) {
-            previewContentHeight = result.toInt();
-        });
+    QScrollBar* scrollBar = m_sourceEditor->verticalScrollBar();
+    if (scrollBar->maximum() <= 0)
+        return;
 
-    const int previewHeight = m_webView->height();
-    const double previewVisibleRatio = static_cast<double>(previewHeight) / previewContentHeight;
+    const double ratio = static_cast<double>(scrollBar->value()) / scrollBar->maximum();
+    m_lastPreviewRatio = ratio;
+
+    m_syncing = true;
+    setPreviewScrollRatio(ratio);
 
-    // 计算比例修正系数（考虑padding等因素）
-    return (1.0 - previewVisibleRatio) / (1.0 - editorVisibleRatio);
+    // 短暂锁定，避免 JS 侧回读滚动位置再次触发编辑器滚动
+    QTimer::singleShot(100, this, [this] {
+        m_syncing = false;
+    });
 }
 
-void MarkdownPreviewWidget::syncEditorToPreview() {
-    //if (m_syncing) return;
-    m_syncing = true;
+void MarkdownPreviewWidget::syncPreviewToEditor(double ratio)
+{
+    if (!m_sourceEditor || m_syncing)
+        return;
 
-    // 计算滚动比例
     QScrollBar* scrollBar = m_sourceEditor->verticalScrollBar();
-    const double ratio = static_cast<double>(scrollBar->value()) / scrollBar->maximum();
+    if (scrollBar->maximum() <= 0)
+        return;
 
-    // 异步执行滚动操作
-    m_webView->page()->runJavaScript(
-        QString("window.scrollTo(0, document.documentElement.scrollHeight * %1);")
-            .arg(ratio)
-    );
+    m_lastPreviewRatio = ratio;
+    m_syncing = true;
+    scrollBar->setValue(qRound(ratio * scrollBar->maximum()));
+
+    QTimer::singleShot(100, this, [this] {
+        m_syncing = false;
+    });
+}
+
+void MarkdownPreviewWidget::pollPreviewScroll()
+{
+    if (!m_sourceEditor || m_syncing || !m_webView)
+        return;
 
-    // 200ms后解除同步锁定
-    //QTimer::singleShot(200, this, [this](){ m_syncing = false; });
+    const int generation = m_loadGeneration;
+    m_webView->page()->runJavaScript(
+        "var e = document.documentElement;"
+        "var h = e.scrollHeight - e.clientHeight;"
+        "h > 0 ? (window.scrollY || e.scrollTop || 0) / h : 0;",
+        [this, generation](const QVariant &result) {
+            if (generation != m_loadGeneration || !m_sourceEditor || m_syncing)
+                return;
+
+            const double ratio = result.toDouble();
+            if (qAbs(ratio - m_lastPreviewRatio) < 0.0005)
+                return;
+
+            m_lastPreviewRatio = ratio;
+
+            QScrollBar* scrollBar = m_sourceEditor->verticalScrollBar();
+            if (scrollBar->maximum() <= 0)
+                return;
+
+            m_syncing = true;
+            scrollBar->setValue(qRound(ratio * scrollBar->maximum()));
+            QTimer::singleShot(100, this, [this] {
+                m_syncing = false;
+            });
+        });
 }
 
+void MarkdownPreviewWidget::onPreviewLoadFinished(bool ok)
+{
+    if (!ok || !m_sourceEditor)
+        return;
+
+    // 在 JS 真正执行 scrollTo 后再记录比例并启动轮询，
+    // 避免轮询读到恢复前的旧位置导致滚动被拉回去。
+    const double ratio = m_lastScrollRatio;
+    const int generation = m_loadGeneration;
+    m_webView->page()->runJavaScript(
+        QString("var e = document.documentElement;"
+                "var h = e.scrollHeight - e.clientHeight;"
+                "window.scrollTo(0, %1 * (h > 0 ? h : 0));").arg(ratio),
+        [this, ratio, generation](const QVariant &) {
+            if (generation != m_loadGeneration)
+                return;
+            m_lastPreviewRatio = ratio;
+            if (m_sourceEditor && m_scrollSyncTimer && !m_scrollSyncTimer->isActive())
+                m_scrollSyncTimer->start();
+        }
+    );
+}
 
-void MarkdownPreviewWidget::scheduleUpdate() {
-    m_lastScrollPosition = m_webView->page()->scrollPosition().y();
+void MarkdownPreviewWidget::scheduleUpdate()
+{
+    // 记录当前预览比例，内容刷新后尽量维持阅读位置
+    m_lastScrollRatio = m_lastPreviewRatio;
     m_updateTimer->start(200); // 200ms防抖
 }
 
-void MarkdownPreviewWidget::performUpdate() {
-    if (!m_sourceEditor) return;
+void MarkdownPreviewWidget::performUpdate()
+{
+    if (!m_sourceEditor)
+        return;
+
+    // 刷新期间暂停轮询，避免在页面重新加载过程中误同步
+    if (m_scrollSyncTimer)
+        m_scrollSyncTimer->stop();
 
     const QString content = m_sourceEditor->toPlainText();
     const QString html = generateHtml(content);
 
+    ++m_loadGeneration;
     m_webView->setHtml(html, QUrl("qrc:/"));
-
-    // 延迟恢复滚动位置
-    QTimer::singleShot(50, this, [this] {
-        m_webView->page()->runJavaScript(
-            QString("window.scrollTo(0, %1);").arg(m_lastScrollPosition)
-        );
-    });
 }
 
-QString MarkdownPreviewWidget::generateHtml(const QString& markdown) {
+QString MarkdownPreviewWidget::generateHtml(const QString& markdown)
+{
     // 使用 QJsonDocument 正确序列化字符串
     QJsonArray a;
     a.append(QJsonValue(markdown));
@@ -223,6 +269,7 @@ QString MarkdownPreviewWidget::generateHtml(const QString& markdown) {
             <meta charset="utf-8">
             %1
             <script src="qrc:/markdown/marked.min.js"></script>
+            <script src="qrc:///qtwebchannel/qwebchannel.js"></script>
         </head>
         <body>
             <article class="markdown-body">
@@ -237,6 +284,19 @@ QString MarkdownPreviewWidget::generateHtml(const QString& markdown) {
                     img.style.maxWidth = '100%';
                     img.style.height = 'auto';
                 });
+
+                // 通过 QWebChannel 将预览区滚动事件实时通知给 C++ 侧
+                new QWebChannel(qt.webChannelTransport, function(channel) {
+                    const bridge = channel.objects.markdownPreview;
+                    if (!bridge) return;
+                    window.addEventListener('scroll', function() {
+                        const e = document.documentElement;
+                        const h = e.scrollHeight - e.clientHeight;
+                        if (h > 0) {
+                            bridge.syncPreviewToEditor((window.scrollY || e.scrollTop || 0) / h);
+                        }
+                    });
+                });
             </script>
         </body>
         </html>
@@ -244,12 +304,27 @@ QString MarkdownPreviewWidget::generateHtml(const QString& markdown) {
       .arg(escapedMarkdown); // 直接插入已转义内容
 }
 
-void MarkdownPreviewWidget::setDarkTheme(bool enabled) {
+void MarkdownPreviewWidget::setDarkTheme(bool enabled)
+{
     m_darkMode = enabled;
     scheduleUpdate();
 }
 
-void MarkdownPreviewWidget::initWebView() {
+void MarkdownPreviewWidget::setPreviewScrollRatio(double ratio)
+{
+    if (!m_webView || !m_sourceEditor)
+        return;
+
+    m_lastPreviewRatio = ratio;
+    m_webView->page()->runJavaScript(
+        QString("var e = document.documentElement;"
+                "var h = e.scrollHeight - e.clientHeight;"
+                "window.scrollTo(0, %1 * (h > 0 ? h : 0));").arg(ratio)
+    );
+}
+
+void MarkdownPreviewWidget::initWebView()
+{
     // 禁用上下文菜单
     //m_webView->setContextMenuPolicy(Qt::NoContextMenu);
 
diff --git a/src/widgets/markdownpreviewwidget.h b/src/widgets/markdownpreviewwidget.h
index c795e91ef891294e379e9ae1e387e979aeae0179..c82537c187e9c2b88bd49e32ef2ce5fc6cd343dc 100644
--- a/src/widgets/markdownpreviewwidget.h
+++ b/src/widgets/markdownpreviewwidget.h
@@ -12,6 +12,22 @@
 #include <QProcessEnvironment>
 
 // 用于实现调用浏览器打开超链接
+class QWebChannel;
+class MarkdownPreviewWidget;
+
+// 仅暴露滚动同步接口给 QWebChannel，避免把整个 QWidget 暴露给页面
+class MarkdownPreviewBridge : public QObject {
+    Q_OBJECT
+public:
+    explicit MarkdownPreviewBridge(MarkdownPreviewWidget* widget);
+
+public slots:
+    void syncPreviewToEditor(double ratio);
+
+private:
+    MarkdownPreviewWidget* m_widget;
+};
+
 class MarkdownWebPage : public QWebEnginePage {
     Q_OBJECT
 public:
@@ -34,35 +50,35 @@ public:
     void setSourceEditor(QTextEdit* editor);
     void setDarkTheme(bool enabled);
 
-    static bool isSupport()/* {
-        // 检测是否有设置 QTWEBENGINE_DISABLE_SANDBOX
-        if (QProcessEnvironment::systemEnvironment().value("QTWEBENGINE_DISABLE_SANDBOX") == "1") {
-            return true;
-        }
-        return QProcessEnvironment::systemEnvironment().value("USER") != "root";
-    }*/;
+    static bool isSupport();
+
+    void syncPreviewToEditor(double ratio);
 
 private slots:
     void scheduleUpdate();
     void performUpdate();
 
-    void setupScrollSync();
     void syncEditorToPreview();
+    void pollPreviewScroll();
+    void onPreviewLoadFinished(bool ok);
 
 private:
     void initWebView();
-    void updateScrollPosition();
     QString generateHtml(const QString& markdown);
-    double calculateSyncRatio();
+    void setPreviewScrollRatio(double ratio);
 
-    QWebEngineView* m_webView;
-    MarkdownWebPage* m_webPage;
+    QWebEngineView* m_webView = nullptr;
+    MarkdownWebPage* m_webPage = nullptr;
+    QWebChannel* m_webChannel = nullptr;
+    MarkdownPreviewBridge* m_bridge = nullptr;
     QTextEdit* m_sourceEditor = nullptr;
-    QTimer* m_scrollSyncTimer;
-    QTimer* m_updateTimer;
+    QTimer* m_updateTimer = nullptr;
+    QTimer* m_scrollSyncTimer = nullptr;
     bool m_syncing = false;
-    int m_lastScrollPosition = 0;
     bool m_darkMode = false;
+    double m_lastScrollRatio = 0.0;
+    double m_lastPreviewRatio = 0.0;
+    int m_loadGeneration = 0;
 };
 #endif
 #endif
diff --git a/src/widgets/toast.cpp b/src/widgets/toast.cpp
index fbb389becb9afccb8a0be4aa76436d5e1cc392b0..6f6e56c6bc2e693b24aabe719cf8ee5a55ad433c 100644
--- a/src/widgets/toast.cpp
+++ b/src/widgets/toast.cpp
@@ -19,6 +19,13 @@
 
 #include "toast.h"
 #include <QApplication>
+#include <DGuiApplicationHelper>
+#include <QIcon>
+
+static QString currentThemeName()
+{
+    return Dtk::Gui::DGuiApplicationHelper::instance()->themeType() == Dtk::Gui::DGuiApplicationHelper::DarkType ? "dark" : "light";
+}
 
 Toast::Toast(QWidget *parent)
     : QFrame(parent)
@@ -49,8 +56,10 @@ Toast::Toast(QWidget *parent)
     setGraphicsEffect(m_effect);
     hide();
 
-    setTheme(DThemeManager::instance()->theme());
-    connect(DThemeManager::instance(), &DThemeManager::themeChanged, this, &Toast::setTheme);
+    setTheme(currentThemeName());
+    connect(Dtk::Gui::DGuiApplicationHelper::instance(), &Dtk::Gui::DGuiApplicationHelper::themeTypeChanged, this, [this](Dtk::Gui::DGuiApplicationHelper::ColorType) {
+        setTheme(currentThemeName());
+    });
 
     connect(m_reloadBtn, &QPushButton::clicked, this, [=] {
         hideAnimation();
@@ -108,16 +117,18 @@ void Toast::setOnlyShow(bool onlyshow)
     m_onlyshow = onlyshow;
 
     if (m_onlyshow) {
-        m_closeBtn = new DImageButton;
+        m_closeBtn = new QPushButton;
         m_closeBtn->setFixedSize(14, 14);
         m_layout->addWidget(m_reloadBtn);
         m_layout->addWidget(m_saveAsBtn);
         m_layout->addWidget(m_closeBtn);
-        initCloseBtn(DThemeManager::instance()->theme());
+        initCloseBtn(currentThemeName());
 
-        connect(DThemeManager::instance(), &DThemeManager::themeChanged, this, &Toast::initCloseBtn);
-        connect(m_closeBtn, &DImageButton::clicked, this, &Toast::hideAnimation);
-        connect(m_closeBtn, &DImageButton::clicked, this, &Toast::closeBtnClicked);
+        connect(Dtk::Gui::DGuiApplicationHelper::instance(), &Dtk::Gui::DGuiApplicationHelper::themeTypeChanged, this, [this](Dtk::Gui::DGuiApplicationHelper::ColorType) {
+            initCloseBtn(currentThemeName());
+        });
+        connect(m_closeBtn, &QPushButton::clicked, this, &Toast::hideAnimation);
+        connect(m_closeBtn, &QPushButton::clicked, this, &Toast::closeBtnClicked);
     }
 }
 
@@ -208,9 +219,8 @@ void Toast::setOpacity(qreal opacity)
 
 void Toast::initCloseBtn(QString theme)
 {
-    m_closeBtn->setNormalPic(QString(":/images/close_%1_%2.svg").arg("normal", theme));
-    m_closeBtn->setHoverPic(QString(":/images/close_%1_%2.svg").arg("hover", theme));
-    m_closeBtn->setPressPic(QString(":/images/close_%1_%2.svg").arg("press", theme));
+    m_closeBtn->setIcon(QIcon(QString(":/images/close_%1_%2.svg").arg("normal", theme)));
+    m_closeBtn->setStyleSheet("QPushButton { border: none; }");
 }
 
 void Toast::showEvent(QShowEvent *e)
diff --git a/src/widgets/toast.h b/src/widgets/toast.h
index 3912f15539d13d0a81675fac74a82e4c454de51f..e47a7d76ca3bc66e248125dd7522042bbf6229fd 100644
--- a/src/widgets/toast.h
+++ b/src/widgets/toast.h
@@ -28,8 +28,6 @@
 #include <QPushButton>
 
 #include <dhidpihelper.h>
-#include <dthememanager.h>
-#include <dimagebutton.h>
 #include <dgraphicsgloweffect.h>
 #include <QHBoxLayout>
 
@@ -82,7 +80,7 @@ private:
 
     QPropertyAnimation *m_animation = nullptr;
     DGraphicsGlowEffect *m_effect = nullptr;
-    DImageButton *m_closeBtn;
+    QPushButton *m_closeBtn;
     QPushButton *m_reloadBtn;
     QPushButton *m_saveAsBtn;
 };
diff --git a/src/window.cpp b/src/window.cpp
index ab2b7c5803f8e82774be229380791721538156e1..1541fa440630986d73d4906ee0ffde2ac7a501c6 100644
--- a/src/window.cpp
+++ b/src/window.cpp
@@ -23,8 +23,8 @@
 #include "window.h"
 #include "toolbar.h"
 #include <DAnchors>
-#include <dthememanager.h>
-#include <DToast>
+#include <DGuiApplicationHelper>
+#include <dtoast.h>
 #include "utils.h"
 
 #include <DSettingsWidgetFactory>
@@ -166,8 +166,6 @@ Window::Window(DMainWindow *parent)
 
     connect(qApp, &QGuiApplication::focusWindowChanged, this, &Window::handleFocusWindowChanged);
 
-    // 允许设置背景
-    setEnableWindowBackground(1);
 
     WaylandActivator::instance();
 }
@@ -209,7 +207,7 @@ void Window::initTitlebar()
     ToolBar *toolBar = new ToolBar;
     toolBar->setTabbar(m_tabbar);
 
-    titlebar()->setCustomWidget(toolBar, Qt::AlignVCenter, false);
+    titlebar()->setCustomWidget(toolBar, false);
     titlebar()->setAutoHideOnFullscreen(true);
     titlebar()->setSeparatorVisible(true);
     titlebar()->setFixedHeight(40);
@@ -778,7 +776,6 @@ void Window::popupSettingsDialog()
     dialog->widgetFactory()->registerWidget("fontcombobox", Settings::createFontComBoBoxHandle);
     dialog->setProperty("_d_dtk_theme", "dark");
     dialog->setProperty("_d_QSSFilename", "DSettingsDialog");
-    DThemeManager::instance()->registerWidget(dialog);
 
     dialog->updateSettings(m_settings->settings);
     m_settings->dtkThemeWorkaround(dialog, "dlight");
@@ -1258,9 +1255,9 @@ void Window::loadTheme(const QString &path)
 
     bool isDark = (QColor(backgroundColor).lightness() < 128);
     if (isDark) {
-        DThemeManager::instance()->setTheme("dark");
+        Dtk::Gui::DGuiApplicationHelper::instance()->setPaletteType(Dtk::Gui::DGuiApplicationHelper::DarkType);
     } else {
-        DThemeManager::instance()->setTheme("light");
+        Dtk::Gui::DGuiApplicationHelper::instance()->setPaletteType(Dtk::Gui::DGuiApplicationHelper::LightType);
     }
 
     changeTitlebarBackground(tabbarStartColor, tabbarEndColor);