Font isn't uniform

Hello,

In the right sidebar widget, how do I get uniform font for

This is my student, Rejat K, playing Gavotte in g minor (2018) by J.S. Bach. This is how he played in 2014: https://proviolin.com/performances/student-performances/ and

This is my student, Aaron R, learning the 1st page of the Kabalevsky Violin Concerto (2018). He played Concerto for Two Violins by Bach in 2014: http://newsite.proviolin.com/?page_id=37

I did a shift alt 2 for heading 2 but the font doesn’t look the same throughout for the above explanations on newsite.proviolin.com.

Please give me step by step instructions on how to change this.

Thank you.