//ダッシュボードのスタイルを設定します
dashboardTheme.Common.Margins = new C1.Framework.Thickness(30,30,30,30);
dashboardTheme.Common.Padding = new C1.Framework.Thickness(20,20,20,20);
dashboardTheme.Common.BackColor = Color.Red;

//項目コンテナのスタイルを設定します
DashboardTheme dashboardTheme = c1DashboardLayout1.Styles;
dashboardTheme.ItemContainer.BackColor = Color.Orange;      
dashboardTheme.ItemContainer.PlaceHolderColor = Color.LightBlue;
dashboardTheme.ItemContainer.ToolIcon =Image.FromFile(@"C:\ToolIcon.png");
dashboardTheme.ItemContainer.ToolIconColor = Color.White;
          
//ヘッダーのスタイルを設定します           
dashboardTheme.ContainerHeader.BackColor = Color.Yellow;
dashboardTheme.ContainerHeader.ForeColor = Color.Green;