获取系统主题颜色

[DllImport("uxtheme.dll", EntryPoint = "#95")]
public static extern uint GetImmersiveColorFromColorSetEx(uint dwImmersiveColorSet, uint dwImmersiveColorType, bool bIgnoreHighContrast, uint dwHighContrastCacheMode);
[DllImport("uxtheme.dll", EntryPoint = "#96")]
public static extern uint GetImmersiveColorTypeFromName(IntPtr pName);
[DllImport("uxtheme.dll", EntryPoint = "#98")]
public static extern int GetImmersiveUserColorSetPreference(bool bForceCheckRegistry, bool bSkipCheckOnFail);
// Get theme color
public Color GetThemeColor()
{
    var colorSetEx = GetImmersiveColorFromColorSetEx(
        (uint)GetImmersiveUserColorSetPreference(false, false),
        GetImmersiveColorTypeFromName(Marshal.StringToHGlobalUni("ImmersiveStartSelectionBackground")),
        false, 0);

    var colour = Color.FromArgb((byte)((0xFF000000 & colorSetEx) >> 24), (byte)(0x000000FF & colorSetEx),
        (byte)((0x0000FF00 & colorSetEx) >> 8), (byte)((0x00FF0000 & colorSetEx) >> 16));

    return colour;
}