Main Navigation Menu Font Size CSS

[Linford]

Hi

Im trying to change just the font size of my main navigation menu at the top of my website. ive found the section of code i need to edit in the inspect element section but when i head over to change it in the shopify theme code editing tool i cant find the section i need to change in the theme.scss.liquid.

If anyone knows how i can change this i would appriciate it very much! Thank You

Lin