how to remove post Column Boarder

Hi there.

can you provide a link to your Site so i can see what the fix is.
You can edit your original topic and use the Site URL field to share the link privately.

Hi, updated.

Can you check now?

Go to Additional CSS field in the customizer and remove this CSS:

.generate-columns .inside-article {
    background-color: rgba(0,0,0,0.02);
    transform: scale(1);
    box-shadow: 0px 0px 0px 1px rgba(214,218,222,1);
    transition: all 0.1s ease-in;
}

Hi, it worked. thank you.

Another question,

How can I change the font size of the title: https://prnt.sc/s9louo ?

Hi there,

you can change the Archive Content Title (H2) font size in Customizer > Typography > Headings