小三角旋转180度(就是上下翻转)

<tempalte>
    <i class="iconfont icon-a-xiala" :class="{ 'triangle-rotate': isSubPlanPopup }"></i>
</template>
<script>
export default{
    data(){
        return {
            isSubPlanPopup: false
        }
    },
    methods:{
        xxxFunc(){
            this.isSubPlanPopup = true;
        }
    }
}
data(){}
</script>
<style>
    .triangle-rotate {
      transform: rotate(-180deg);
    }
</style>