<PackageReference Include="System.Drawing.Common" Version="11.0.0-preview.1.26104.118" />

Windows.Win32.Graphics.GdiPlus.LinearGradientMode

namespace Windows.Win32.Graphics.GdiPlus { internal enum LinearGradientMode { LinearGradientModeHorizontal, LinearGradientModeVertical, LinearGradientModeForwardDiagonal, LinearGradientModeBackwardDiagonal } }