Question

Here is what I have, but it is not working:

 if(window.width() < 1000)
document.getElementsByTagName('body')[0].id="be"
else
document.getElementsByTagName('body')[0].id="bd"
;

Please tell me what I am writing wrong. Please don’t tell other solutions, please just fix this code.

Basically, I want to give a different ID to the BODY tag of a website if the browser window size is less than 1000px.

Answer 1

Here you go:

document.body.id = window.innerWidth < 1000 ? 'be' : 'bd';

---

Place this code at the bottom of your page:

<script>
    function setBodyId() {
        document.body.id = window.innerWidth < 1000 ? 'be' : 'bd';
    }           
    window.onload = setBodyId;
    window.onresize = setBodyId;
</script>

Live demo: http://jsfiddle.net/simevidas/THqXB/