<div id="app">
<header ref="header"></header>
<section ref="content" class="content"></section>
<footer ref="footer">
</footer>
</div>
new Vue({
el: "#app",
mounted(){
let header = this.$refs.header.offsetHeight
let footer = this.$refs.footer.offsetHeight
let win = window.innerHeight;
let size = win - footer - header;
this.$refs.content.style.minHeight = win + "px"
}
});