The specific of the way controls are built (HTML and CSS) does not give an easy to use option when you use controls with HTML/CSS templates.
The only way is rework the template in way not to use global CSS styles applied directly to a specific HTML element. Otherwise it is not possible to avoid the unwanted styles that will be applied to the elements that build the ASP.NET AJAX control.
Building an application using more than one third party code (themes, controls, etc.) will always get into a CSS mixture problem, so the best way to control things is to rework the theme not to use global CSS styles.
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