模态弹出过渡 - 按钮的弹出窗口？

I have a question on a transition for a modal popup. The popup comes from a button. I'm currently using the css below, which isn't bad. But is there any way to make the transition look like the modal is popping up from the button I just pressed? FYI, i'm only intermdiate with css. Do I need some JS for this?I have a question on a transition for a modal p