can i format the HTML alert box into my colors and style with css?

i want to show an alert when someone click on Paypal button and the alert should say you will be directed to Pa开发者_运维百科ypal website but the basic html alert ox is awful in style ,

is there a way to improve its styling ?

or i have to design a div and code its functionality too?

No. However, you can create a DIV tag which will be positioned absolute to look like an alert box or use jQuery UI to easily create dialog boxes, here http://jqueryui.com/demos/dialog/