Hi,

You can add more this code to Customize > Custom CSS to change color & size for "Read More" button:

.penci-readmore-btn.penci-btn-make-button a{ background-color: #ff0000; font-size: 14px; }

Change value 14 to font size as you want.

Change color code ff0000 to any color code as you want. You can get a color code here

Best Regards,

PenciDesign