问如何在手机Jquery上点击第二次才触发动作

EN

$(document).ready(function() {
  if (window.matchMedia('(max-width: 767px)').matches) {
    var clicks = true;
    $(window).bind('click', function(event){
        if (clicks) {
           clicks = false;
        } else {
          alert('Hi there! you just ckick twice');
          clicks = true;
        }
    });
   }
});