How to make arrows on click?

Question

css

welovepavel.esy.es/1
https://vk.com/doc309751762_431727389
display none if you remove it, you will understand what arrows I mean.
common.js
main.css
in theory they should appear when you click on the curtain and close with the rest of the menu.... Any
suggestions???
Thanks

Answer 1

I didn't understand the question! Here only to the fortune teller for a clear description of the issue.
More precise explanation.
"Blinds" are from the field of design of apartments, premises.

Answer 2

What do you need?

.mc_item_wrap.active:after {
    content: "";
    width: 18px;
    height: 9px;
    background-image: url(../img/mc_c_ar.png);
    position: absolute;
    margin: 11px -11px; 
}