Change Lightbox design

I tried to override the default lightbox to suit my needs, but couldn’t add functionality to it. any suggestions please ??

there are three ways

a) use existing form blocks ( input and select ) - you can define any number of fields

or

b) create custom form block, by using them you can redefine all except of border and buttons at bottom.
docs.dhtmlx.com/doku.php?id=dhtm … tails_form

or

c) redefine showLightbox method and show custom form