Changing Background Color of a single Menue Item an its submenue

Is there a possibility to influence Background Color of one Menue Item an subsequently its submenues and the mouse Rollover Color? Like: - Header Secondary Menu Color Options is set to: #1e73be - Menu Hover & Active Background Color ist set to: #81d742 Now I would like to change those settings i.e. for the 4th section of the Menue See at https://www.stiftung-meeresschutz.org/ Thanks for any good ideas in advance :) Ulrich