Hi there,
Welcome to SeaTheme forum.
Please check if there is a cache option on your wordpress, please disable it to check again. If it doesn’t work, may I check your website? Could you please leave your wp-admin access (URL / username/password) by picking up “Set as private reply”?
The submenu BG color is the same as the Header bar, you can also set it via the (“Appearance > Customize: Additional CSS”), like:
.navi-header .sub-menu > li, .navi-header .menu ul.children > li {
background-color: #ccc;
}
Regards!
SeaTheme – FAQs – WordPress Customization – Facebook