如何使按钮大小相同并将所有按钮放在页面上？

I'm using Bootstrap 3 and have 3 buttons of different sizes. I am trying to make them all the same size (based on the size of the largest one) and then center all of them in the middle of the page with space in between them. The buttons either end up not being the same size or not having any space in between them. I want the buttons to be dynamic so I don't want to make them conform to a certain px width.I'm using Bootstrap 3 and have 3 buttons of dif