Configure Sub Menu Style

You will find the setting inside Customize >> Colors >> Sub Menu items

Background Color – Allows you to choose a background color for sub menu.
Text Hover Color – Allows you to choose a text hover color.
Background Hover Color – Allows you to choose a background hover color.

Sub Menu Font – Allows you to select font properties for sub-menu of site.
Select Font Family with Variant
It also allows to download font-family to server instead of using the Google CDN.