<div class="wrap">
  <div id="app">
    <img v-bind:src="imgSrc" v-bind:class="className">
  </div>
</div>
.wrap {
  width: 30%;
}
let app = new Vue({
  el: "#app",
  data: {
    imgSrc:
      "https://images.unsplash.com/photo-1529778873920-4da4926a72c2?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=1576&q=80",
    className: "img-fluid"
  }
});

External CSS

  1. https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/4.1.3/css/bootstrap.min.css

External JavaScript

  1. https://cdnjs.cloudflare.com/ajax/libs/vue/2.6.11/vue.min.js