Hello Guemes,

Thanks for reaching out to us.

Could you please share your website url with me?

Thanks

Provided hidden

Never mind; I figured it out. AI told me to add custom css, which I did but it didn't work. Then it told me to use the Mega Menu controls - which seemed strange because this is a dropdown Joomla menu not a Mega Menu. But I tried it and it didn't work. Then I removed the custom css and used the MM controls and it's now working.

Now I would like to change the font size of the dropdown but don't know where to look. I don't want to change the Main Menu, just the dropdown.

We have documenation, you don't have ask AI each time :) link: https://www.joomshaper.com/documentation/helix-framework/customization-tips

About your questions. You don't have dropdown menu, at least I don't see it. Anyway, based on my own site

Bg color for submenu (custom css method)

.sp-megamenu-parent .sp-dropdown .sp-dropdown-inner {
  background: rgb(255, 246, 225); }

font-size & color for submenu items (custom css method)

.sp-megamenu-parent .sp-dropdown li.sp-menu-item > a, 
.sp-megamenu-parent .sp-dropdown li.sp-menu-item span 
{font-size: 16px; color: black;} 

of course, use your own colors (hex code or rgb)