PdfHtmlTemplateOpacity Property

The opacity as a value between 0 and 1 to be applied to entire template. For example, setting this property to 0.75 will lower the opacity to 75% . The default value is 1 and the rendered PDF content will have its original opacity. If you want to control only the opacity of the HTML template background, you can do this by setting the body element style to background-color: rgba(255, 255, 255, 0.75), which will set the opacity to 0.75

public float Opacity { get; set; }