function ch_product(o) {
    o.className = "product_tit_on";
    var j;
    var id;
    var e;
    for (var i = 1; i <= 4; i++) {
        id = "product_tit" + i;
        j = document.getElementById(id);
        e = document.getElementById("product_con" + i);
        if (id != o.id) {
            j.className = "product_tit_off";
            e.style.display = "none";
        } else {
            e.style.display = "block";
        }
    }
}

function ch_wenda(o){
  o.className="wenda_tit_on";
  var j;
  var id;
  var e;
  for(var i=1;i<=2;i++){
    id ="wenda_tit"+i;
    j = document.getElementById(id);
    e = document.getElementById("wenda_con"+i);
    if(id != o.id){
      j.className="wenda_tit_off";
      e.style.display = "none";
    }else{
      e.style.display = "block";
    }
  }
}

function ch_zhaopin(o){
  o.className="zhaopin_tit_on";
  var j;
  var id;
  var e;
  for(var i=1;i<=2;i++){
    id ="zhaopin_tit"+i;
    j = document.getElementById(id);
    e = document.getElementById("zhaopin_con"+i);
    if(id != o.id){
      j.className="zhaopin_tit_off";
      e.style.display = "none";
    }else{
      e.style.display = "block";
    }
  }
}