function layer() {
	document.getElementById('layer').style.display = 'block';
	document.getElementById('layer').style.position = 'absolute';
	document.getElementById('layer').style.top = '100px';
	document.getElementById('layer').style.left = '150px';

}

function layerNone() {
	document.getElementById('layer').style.display = 'none';
}

var old_id = '';
var is_opened  = 'none';

function toggle( id ) {

    id_obj = document.getElementById(id);
    is_opened = id_obj.style.display;

	if (document.getElementById('c1') !== null && id != 'c1')
	{
		document.getElementById('c1').style.display = 'none';
	}

	if (document.getElementById('z1') !== null && id != 'z1')
	{
		document.getElementById('z1').style.display = 'none';
	}

    if (old_id != '' && is_opened == 'none') {
        old_id_obj = document.getElementById(old_id);
        old_id_obj.style.display = 'none';		
    }

    if (old_id != id || is_opened == 'none') {
        id_obj.style.display = 'block';
    }

    old_id = id;
}

function langalert(lang) {
	if ( lang == 'en') {
		alert('This website is under construction!\nPlease visit later!');
	}
}