thumbnail sizes are different

thumbnail size are different on my website. I have seen the post of equal heights and made the changes in afp-functions.js but it is not working and i made changes in css also
li.afp-single-item {
width:150px;
min-height: 250px;
}
but this change is also not reflected on my web page.So please some one help me for solving me this issue.

https://wordpress.org/plugins/awesome-filterable-portfolio/