make the menu open selected automatically on small screens

Hi,
how can I make make the menu selected automaticallly on small screens on bottom? I want the menue selected (opened/ shown) to any page and post. There must be a simple css code. Which?

I found at https://css-tricks.com/responsive-menu-concepts :

2. Select
This concept hides the basic menu on small screens and shows a select menu instead.
[some code]

Is that the right direction I have to search for a solution?

please help
thank you
Eckard

• This topic was modified 6 years, 8 months ago by egerlach.
• This topic was modified 6 years, 8 months ago by egerlach.
• This topic was modified 6 years, 8 months ago by egerlach.

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