The site you mentioned is using a theme named greenbox , this theme is based on snowflat theme which is default theme in q2a .
They modified css according to thier need
Their mobile theme uses "Lightbox" theme , they created themselve by modifying some css !
You can message them to get that theme !
Their admin account :- https://ansbari.com/user/Admin
Src:: quesnit.com/29/