Fix dpi for setting form

Author: lingyongji

.gitignore

@@ -4,7 +4,6 @@
 
 /.dotnet_cli/.dotnet
 /.vs
-/bin/Debug/net8.0-windows
-/LiteMonitor.Updater/obj
-/obj
-/bin/Debug
+/bin/*
+/obj/*
+/LiteMonitor.Updater/*

src/UI/Settings/SettingsBase.cs

@@ -26,6 +26,7 @@ public class SettingsPageBase : UserControl, ISettingsPage
 
         public SettingsPageBase() 
         {
+            this.AutoScaleMode = AutoScaleMode.None;
             this.BackColor = GlobalBackColor; 
             this.Dock = DockStyle.Fill;
             this.DoubleBuffered = true;

src/UI/SettingsForm.cs

@@ -16,6 +16,7 @@ public class SettingsForm : Form
         private Settings _draftCfg; // Draft Settings
         private UIController _ui;
         private MainForm _mainForm;
+        private int _lastDpi = 96;
 
         private FlowLayoutPanel _pnlNavContainer; 
         private BufferedPanel _pnlContent; // 使用现有的 BufferedPanel
@@ -57,13 +58,17 @@ public SettingsForm(Settings cfg, UIController ui, MainForm mainForm)
             _draftCfg = _cfg.DeepClone();
 
             InitializeComponent(); 
+            _lastDpi = this.DeviceDpi;
 
             // ★★★ 关键点 1：构造时就初始化所有页面 ★★★
             InitPages(); 
         }
 
         private void InitializeComponent()
         {
+            // SettingsForm uses manual UIUtils scaling during construction.
+            // Disable WinForms auto-rescaling on cross-monitor DPI changes to avoid double scaling.
+            this.AutoScaleMode = AutoScaleMode.None;
             UIUtils.ScaleFactor = this.DeviceDpi / 96f;
 
             this.Size = new Size(UIUtils.S(820), UIUtils.S(680));
@@ -248,5 +253,41 @@ private void ApplySettings()
             // 将 Live 环境中由插件生成的最新监控项同步回 Draft，并保留动态显示属性
             SettingsChanger.RebaseDraftMonitorItems(_cfg, _draftCfg);
         }
+
+        protected override void OnDpiChanged(DpiChangedEventArgs e)
+        {
+            base.OnDpiChanged(e);
+
+            // Settings UI uses manual sizing based on the initial DPI.
+            // Keep fonts visually stable across monitors to avoid extra whitespace
+            // when the form moves between 150% and 100% displays.
+            if (_lastDpi > 0 && e.DeviceDpiNew > 0 && _lastDpi != e.DeviceDpiNew)
+            {
+                float ratio = (float)_lastDpi / e.DeviceDpiNew;
+                RescaleFonts(this, ratio);
+                foreach (var page in _pages.Values)
+                {
+                    if (!page.IsDisposed && page.Parent == null)
+                    {
+                        RescaleFonts(page, ratio);
+                    }
+                }
+                _lastDpi = e.DeviceDpiNew;
+            }
+        }
+
+        private static void RescaleFonts(Control root, float ratio)
+        {
+            if (root.Font != null)
+            {
+                float newSize = Math.Max(1f, root.Font.Size * ratio);
+                root.Font = new Font(root.Font.FontFamily, newSize, root.Font.Style);
+            }
+
+            foreach (Control child in root.Controls)
+            {
+                RescaleFonts(child, ratio);
+            }
+        }
     }
-}
+}

src/UI/TaskbarForm.cs

@@ -57,11 +57,12 @@ public TaskbarForm(Settings cfg, UIController ui, MainForm mainForm)
             TopMost = false;
             DoubleBuffered = true;
 
+            ReloadLayout();
+
             _bizHelper.CheckTheme(true);
             _bizHelper.FindHandles();
 
             _bizHelper.AttachToTaskbar();
-            ReloadLayout();
             _winHelper.ApplyLayeredStyle(_bizHelper.TransparentKey, _cfg.TaskbarClickThrough);
 
             _timer.Interval = Math.Max(_cfg.RefreshMs, 60);