Editing "Harmony" Logo (or removing it)

I am editing the theme but can’t find where to change the “Harmony” text on the left side of the header image. I don’t mind leaving it there, but would like to be able to edit the little icon above the word and change “Harmony” to the site name. Where would I be able to do this?

https://learningexploratorium.com/

Thank you,

DebbyK