Hello,

I watched the video you attached.

You mentioned that you need to change the font size of the page title only for the post pages. That’s why I provided the specific Custom CSS.

You can use the following Custom CSS that will work for all pages.

.page-title .entry-title {
    font-size: 60px;
}

And you can set the font-size for mobile devices by using the same Custom CSS in the Custom CSS for Mobile area and adjust the size according to your needs.

Best Regards