Vue JS

            <div class="item-master" @click="changeArrow">
            <div class="item-child" :style="(isActive)? 'display: block'">
                <ul>
                    <li class="item-child-list">Add</li>
                </ul>
            </div>
            </div>
            <div class="item-child" :style="(isActive)? 'display: block'">
                <ul>
                    <li class="item-child-list">Add</li>
                </ul>
            </div>

            data(){
                return{
                    isActive: false,
                }
            },

           methods: {
            changeArrow: function (e) {
                this.isActive = !this.isActive;
            },
            }