Here is my code that I used it for client, it will generate 3X4 grid.
Shortcodes:
[catlist id=3 catlink=yes category_count=yes numberposts=12 thumbnail=yes thumbnail_size=150,150 title_limit=25 pagination=yes instance=1]
[catlist id=5 catlink=yes category_count=yes numberposts=12 thumbnail=yes thumbnail_size=150,150 title_limit=25 pagination=yes instance=2]
[catlist id=6 catlink=yes category_count=yes numberposts=12 thumbnail=yes thumbnail_size=150,150 title_limit=25 pagination=yes instance=3]
CSS:
.lcp_catlist {
margin-left: auto;
margin-right: auto;
}
.lcp_catlist li {
width: 33%; /*this is comment if you wish the grid to be 3 in a row put 33%, if 4 then 25% if 2 in a row then 50%*/
text-align: center;
min-height: 150px;
display: inline-block;
vertical-align: top;
margin: 0;
}
.lcp_catlist li:after {
content: '.';
height: 0;
visibility: hidden;
display: block;
clear: both;
}