perf[Style]: refine fixed-header style when open el-dialog

src/layout/components/AppMain.vue

@@ -27,7 +27,14 @@ export default {
 }
 .fixed-header+.app-main {
   padding-top: 50px;
-  height: 100vh;
-  overflow: auto;
+}
+</style>
+
+<style lang="scss">
+// fix css style bug in open el-dialog
+.el-popup-parent--hidden {
+  .fixed-header {
+    padding-right: 15px;
+  }
 }
 </style>