SweetAlert automatically centers itself on the page and looks great no matter if you're using a desktop computer, mobile or tablet. It's even highly customizeable, as you can see below!
http://t4t5.github.io/sweetalert/
A basic sweetalert message
A success message!
A warning message, with a function attached to the "Confirm"-button...
... and by passing a parameter, you can execute something else for "Cancel".
