Vue.js implementing old scripts

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/1.0.24/vue.min.js"></script>
<div id="demo">
  <p>{{message}}</p>
  <input v-model lazy="message">
</div>

JavaScript

var demo = new Vue({
  el: '#demo',
  data: {
    message: 'Hello Vue.js!'
  },
  ready: function() {
        console.log('some old stuff here...');
  			var element = document.getElementById('demo');
        element.setAttribute('style', 'color:red;');
  }
})