Our plugin use a h3 tag to show document / PDF title when display in columns layout. While different WordPress theme has different CSS for h3 and the font size for document / PDF title is too big on some WordPress theme.
What you need to do is just adding the following CSS to your theme.
.bsk-pdfm-columns-single h3 {
font-size: 1.0em !important;
}
You may change 1.0em to 1.2 or 1.5em to change the font size of the document / PDF title when it shown in columns layout.
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