Show/hide elements

HTML

<label id="rulesMgmtLbl">Rules Management</label>
<button id="hide">hide</button>
<button id="show">show</button>
<div id="myelement" style="border: 1px blue solid; background: lightblue;">my element</div>

JavaScript

var myelement = document.getElementById('myelement');
var btnHide = document.getElementById('hide');
var btnShow = document.getElementById('show');
btnHide.addEventListener("click", hide, false);
btnShow.addEventListener("click", show, false);

function show()
{
    myelement.style.display = ''; //or 'block'
}

function hide()
{
    myelement.style.display = 'none';
}