How do I change the page layout from 2 columns to 3 columns in refresh theme?

[Jackeroo]

I'm using the Refresh theme and I want to change the blog collection page from 2 columns to 3-4 columns. I couldn't find the relevant setting in the theme settings, so I'm wondering how to achieve this. 

Thanks in advance for any help from the technical experts.

My Store: https://www.ikoolcore.com/blogs/knowledge-base

[Jackeroo]

solved. but need more tips:
Just add custom css under blog settings:

.article-card__image {
aspect-ratio: 16/9;
}
.blog-articles {
display: grid;
grid-template-columns: repeat(3, minmax(0, 1fr));
}