Function collapse

docsify.js:3713–3729

(el)

    }
    
    function collapse(el) {
      el = getNode(el);
      if (el == null) {
        return
      }
      on(el, 'click', function (ref) {
        var target = ref.target;
    
        if (
          target.nodeName === 'A' &&
          target.nextSibling &&
          target.nextSibling.classList.contains('app-sub-sidebar')
        ) {
          toggleClass(target.parentNode, 'collapse');
        }
      });
    }
    
    function sticky() {
      var cover = getNode('section.cover');