First add this css code in custom.css.

.home-featured .stage, .home-featured .stage .item, .home-featured .stage .thumb{height:400px !important;}
.content_2{height:400px !important;}

Then Edit your Style Sheet like if you are using stylesheet-light-blue.css Edit this file in any editor and come to Line Number 4177 Change height from here.

height: 420px !important;

Note: We are using 400px height in this code you can change this with your requirement.

Thanks