Revert "vant下拉选择组件样式修改"

This reverts commit 0a615a73.

src/components/app-van-select/app-van-select.vue

@@ -163,8 +163,7 @@ export default class AppVanSelect extends Vue {
   .van-dropdown-item__content {
     border-radius: 0 0 15px 15px;
   }
-  .van-dropdown-item--down{
-    top: 170px !important;
+  .dropdown-menu-ative {
   }
 }
 </style>
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