The very first Vue.js example

HTML

<script src="http://vuejs.org/js/vue.min.js"></script>
<div id="demo">
    <odd v-bind:number="number"></odd>
    <input v-model="number">
</div>

CSS

.change-enter-active
{
	background-color: yellow;
	visibility: visible;
	transition: visibility 3s;
}
.change-enter-to
{
	background-color: red;
	visibility: hidden;
}

JavaScript

var data = {
    number: 1
}

Vue.component('odd',
{
	props: ['number', 'oldNumber'],
	template: `<div>{{number}} 
		<transition name="change">
		<div v-if="oldNumber && number > oldNumber"class="up">up</div>
		<div v-if="oldNumber && number < oldNumber" class="down">down</div>
		</transition>
	</div>`,
	watch:
	{
		number: function(number, oldNumber)
		{
			var me = this;
			me.oldNumber = oldNumber;
		}
	}
});

var demo = new Vue({
    el: '#demo',
    data: data
})