How to hide DIV in when you click button?

misteam

I have this on my php file:

And this on my javascript/button:

className: 'qa_reassign'
},{
extend: "selected",
text: "Reassign",
action: function ( e, dt, node, config ) {

//I tried, but this code is not working:

document.getElementById('menu').style.display ='none'; **
**$(".menu").hide();

if(confirm( "Are you sure you want to reassign this transaction?" )){
editor
.edit( table.row( { selected: true } ).index(), false )
.set( 'qa_status', 'Disapproved' )
.set( 'type_ap', '' )
.set( 'qa_approvedby', agent_name )
.submit();
}

},

allan

Can you link to a page showing the issue please?

Thanks,
Allan