clickList(event) {
                var node = this.$refs.msg.childNodes
                var curr = event.currentTarget
                for (var i = 0; i < node.length; i++) {
                    if (node[i].nodeName != ‘#text‘) {
                        if(node[i] == curr){
                            node[i].classList.add("code");
                        }else {
                            node[i].classList.remove("code");
                        }
                    }
                }
            },