Font size on mobile version

Hello, Alekosty!
Thank you for using my plugin.

I guess you are using the Extended Blog Module.

I had to override the default css from divi in order to have it displayed correctly, by adding this css in the plugin styles:

/*
Responsive breakpoint fix for masonry
*/
@media only screen and (max-width: 980px) {

    .acme_grid-item h2.entry-title.acme_grid_title {
        line-height: 50px !important;
        font-size: 48px !important;
    }

    .acme_grid-item p {
        padding-top: 20px;
        line-height: 30px !important;
        font-size: 26px !important;
    }
    .acme_grid-item p.post-meta {
        padding-top: 20px;
        line-height: 18px !important;
        font-size: 16px !important;
    }
}

I had to add those annoying !important attributes for having them override defaults. Anyway, you may try to copy this code into you css and see if it applies any change, otherwise, the path to plugin css is:

/wp-content/plugins/acme-divi-modules/public/css/acme-divi-modules-public.css

Let me know if you can fix your issue.
Take care
Mirko