[Vuejs]-Converting jQuery to Vue – Uncaught TypeError: n.getClientRects is not a function

If you’re going to use Vue, use Vue. Think of the DOM as a side effect of the app state, don’t go rummaging around adding and removing classes on your own.

Instead of DOM traversals, use Vue’s $refs to identify specific elements (when necessary. It often isn’t.)

// in the template:
<a ref="foo">...</a>
// in the component methods:
this.$refs.foo // <-- the anchor tag.   "this" is the component itself.

Instead of adding or removing classes manually, set state variables. The template can check those variables when deciding which classes to include; no DOM traversal necessary.

<div :class="{'large-3': isFoo, 'large-6': !isFoo}">...</div>
    or
<div v-if="isFoo" class="large-3">...</div>
<div v-if="!isFoo" class="large-6">...</div>

data: {
   isFoo: true 
},
methods: {
  foo() {  this.isFoo = !this.isFoo  } // toggle this boolean to swap the classnames
}