解决Cascader 下拉弹出位置问题

package-lock.json

@@ -14027,7 +14027,8 @@
     "vue": {
       "version": "2.5.16",
       "resolved": "https://registry.npmjs.org/vue/-/vue-2.5.16.tgz",
-      "integrity": "sha512-/ffmsiVuPC8PsWcFkZngdpas19ABm5mh2wA7iDqcltyCTwlgZjHGeJYOXkBMo422iPwIcviOtrTCUpSfXmToLQ=="
+      "integrity": "sha512-/ffmsiVuPC8PsWcFkZngdpas19ABm5mh2wA7iDqcltyCTwlgZjHGeJYOXkBMo422iPwIcviOtrTCUpSfXmToLQ==",
+      "dev": true
     },
     "vue-hot-reload-api": {
       "version": "2.3.0",
@@ -14227,15 +14228,6 @@
         }
       }
     },
-    "vue-popperjs": {
-      "version": "1.2.6",
-      "resolved": "https://registry.npmjs.org/vue-popperjs/-/vue-popperjs-1.2.6.tgz",
-      "integrity": "sha512-0SEPDdQY8NxRcDiWXTgW6nMpRcc+rSpcELsLszuPzehBqQ5/9AGAr2OGKh1smwcaRe8Rb1CtE399vNz9+jYorw==",
-      "requires": {
-        "popper.js": "1.14.1",
-        "vue": "2.5.16"
-      }
-    },
     "vue-router": {
       "version": "3.0.1",
       "resolved": "https://registry.npmjs.org/vue-router/-/vue-router-3.0.1.tgz",