Vue.JS 2.5.1 : Uncaught SyntaxError: Unexpected to

I was trying to make a radio button using VueJS and Bootstrap Vue, but this happens when I make it. I'm expecting this to be syntax error just like what it said, but I can't seem find any clue.

So I tried to copy pasted the code, here's the full code of test_radio.php

<!DOCTYPE html>
<html>
<head>
    <link type="text/css" rel="stylesheet" href="//unpkg.com/bootstrap/dist/css/bootstrap.min.css"/>
    <link type="text/css" rel="stylesheet" href="//unpkg.com/bootstrap-vue@latest/dist/bootstrap-vue.css"/>
</head>

<body>
<template>
  <div>
    <b-form-group label="Radios using <code>options</code>">
      <b-form-radio-group id="radios1" v-model="selected" :options="options" name="radioOpenions">
      </b-form-radio-group>
    </b-form-group>

    <b-form-group label="Radios using sub-components">
      <b-form-radio-group id="radios2" v-model="selected" name="radioSubComponent">
        <b-form-radio value="first">Toggle this custom radio</b-form-radio>
        <b-form-radio value="second">Or toggle this other custom radio</b-form-radio>
        <b-form-radio value="third" disabled>This one is Disabled</b-form-radio>
        <b-form-radio :value="{fourth: 4}">This is the 4th radio</b-form-radio>
      </b-form-radio-group>
    </b-form-group>

    <div class="mt-3">
      Selected: <strong>{{ selected }}</strong>
    </div>
  </div>
</template>

    <!-- Vue.js @2.5.1 -->
    <script type="text/javascript" src="js/vue.js"></script>

    <!-- Add this after vue.js -->
    <script src="//unpkg.com/babel-polyfill@latest/dist/polyfill.min.js"></script>
    <script src="//unpkg.com/bootstrap-vue@latest/dist/bootstrap-vue.js"></script>

<!-- The error is below -->
<script>
export default {
  data () {
    return {
      selected: 'first',
      options: [
        { text: 'Toggle this custom radio', value: 'first' },
        { text: 'Or toggle this other custom radio', value: 'second' },
        { text: 'This one is Disabled', value: 'third', disabled: true },
        { text: 'This is the 4th radio', value: {fourth: 4} }
      ]
    }
  }
}
</script>
</body>
</html>

Uncaught SyntaxError: Unexpected token export

I'm pretty sure there's a mistake on the code on Export, but I already checked many times and I can't seem to find the error in the syntax.

I'm still new to Javascript, Vue.JS, and Bootstrap Vue, so any help would be useful, thanks! Anyway this code comes from Bootstrap Vue's documentation.

If you are going to use the CDN approach, VueJS starts out like

<!-- Begin of area that is impacted by VueJS -->
<div id="app">
   <b-form-group label="Radios using <code>options</code>">
     <b-form-radio-group id="radios1" v-model="selected" :options="options" name="radioOpenions">
     </b-form-radio-group>
   </b-form-group>
</div>
<!-- End of area that is impacted by VueJS -->


<script>
 var app = new Vue({
   el: '#app',
   data: {
      ...
      }
   })
<script>

The '#app' is what ties the sections together, not import/export