https://prolif.ru/wp-content/themes/my-style/js/mobile-menu.js?ver=6.7.9

1jQuery("body").ready(function () {
2  var fastVisibleOrNo=0;
3  jQuery("#s-button-menu").on('click',function() {
4    if (jQuery("#site-navigation").is(':hidden')) {
5      fastVisibleOrNo=1;
6    } else {
7      fastVisibleOrNo=0;
8    }
9    setTimeout(function(){
10      if (fastVisibleOrNo) {
11        jQuery("#site-navigation").show(400);
12		if ( jQuery( window ).width() <= 800 ) {
13			const  focusableElements =
14				'button, #s-button-menu, [href], [tabindex]:not([tabindex="-1"])';
15			const modal = document.querySelector('#site-navigation'); // select the modal by it's id
16			const modal_1 = document.querySelector('#s-button-menu'); // select the modal by it's id
17			const firstFocusableElement = modal.querySelectorAll(focusableElements)[0]; // get first element to be focused inside modal
18			const focusableContent = modal.querySelectorAll(focusableElements);
19			const lastFocusableElement = focusableContent[focusableContent.length - 1]; // get last element to be focused inside modal
20			document.addEventListener('keydown', function(e) {
21			  let isTabPressed = e.key === 'Tab' || e.keyCode === 9;
22			  if (!isTabPressed) {
23				return;
24			  }
25			  if (e.shiftKey) { // if shift key pressed for shift + tab combination
26				if (document.activeElement === firstFocusableElement) {
27				  lastFocusableElement.focus();

27 // add focus for the last focusable element
28				  e.preventDefault();
29				}
30			  } else { // if tab key is pressed
31				if (document.activeElement === lastFocusableElement) { // if focused has reached to last focusable element then focus first focusable element after pressing tab
32				  modal_1.focus(); // add focus for the first focusable element
33				  e.preventDefault();
34				}
35			  }
36			});
37			firstFocusableElement.focus();
38		}
39      } else {
40        jQuery("#site-navigation").hide(400);
41      }
42    },200);
43  });
44});