jQuery网站右侧固定在线客服代码

<script type="text/javascript" src="js/jquery-1.7.2.min.js"></script>
<script type="text/javascript">
$(document).ready(function(){

  /* ----- 侧边悬浮 ---- */
  $(document).on("mouseenter", ".suspension .a", function(){
    var _this = $(this);
    var s = $(".suspension");
    var isService = _this.hasClass("a-service");
    var isServicePhone = _this.hasClass("a-service-phone");
    var isQrcode = _this.hasClass("a-qrcode");
    if(isService){ s.find(".d-service").show().siblings(".d").hide();}
    if(isServicePhone){ s.find(".d-service-phone").show().siblings(".d").hide();}
    if(isQrcode){ s.find(".d-qrcode").show().siblings(".d").hide();}
  });
  $(document).on("mouseleave", ".suspension, .suspension .a-top", function(){
    $(".suspension").find(".d").hide();
  });
  $(document).on("mouseenter", ".suspension .a-top", function(){
    $(".suspension").find(".d").hide(); 
  });
  $(document).on("click", ".suspension .a-top", function(){
    $("html,body").animate({scrollTop: 0});
  });
  $(window).scroll(function(){
    var st = $(document).scrollTop();
    var $top = $(".suspension .a-top");
    if(st > 400){
      $top.css({display: 'block'});
    }else{
      if ($top.is(":visible")) {
        $top.hide();
      }
    }
  });
  
});