Hello Radmila,
You can center the alert button by using the following modified alert template :
You need to add the code above between the
AlertTemplate tag in the RadWindowManager's declaration in order to make the button horizontally centered. Additionally, you need to add the following CSS code to the head tag :
For your convenience I have attached a demo to the thread.
I hope this helps.
All the best,
Fiko
the Telerik team