goodtognci
Hi
You have custom code in custom.css file that creating this issue
.categories-list .category-item {
width: 33%;
float: left;
box-sizing: border-box;
padding: 10px;
}
.categories-list .category-item:nth-child(3n+4) {
clear: both;
}
.category-item img {
width: 100%;
max-width: 350px;
height: auto;
}
Remove the code will make it full width and show item one by one, not in two column that is from the custom code.
Regards