function ShowHide()
{
  for( var i = 0; i < arguments.length; i++ )
	{
		 el=document.getElementById( arguments[i] ).style;
		 el.display=(el.display == 'block')? 'none' : 'block';
	}
	return true;
}

function toHide()
{
	var inp = myGetElementsByClassName('to-hide');
	for(i = 0; i < inp.length; i++)
  	{
		inp[i].style.display = 'none';		
  	}
}

function showCourses(id)
{
	toHide();
	document.getElementById(id).style.display='block';
	
	var element = document.getElementById('top-box');
	var langs = myGetElementsByClassName( 'language', element );
	
	var j = langs.length;
	for(var i=0; i<j; i++)
	{
		langs[i].style.color='#ffffff';		
	}
	document.getElementById('prev-' + id).style.color='#fede58';
	
}

function myGetElementsByClassName(classname, node) 
{
	if(!node) 
		node = document.getElementsByTagName("body")[0];
	
	var a = [];
	var re = new RegExp('\\b' + classname + '\\b');
	var els = node.getElementsByTagName("*");
	for(var i=0,j=els.length; i<j; i++)
	if(re.test(els[i].className))a.push(els[i]);
	return a;
}

function doClock()
{
	
	tlimit = tlimit-1;
	min = Math.floor(tlimit / 60);
	sec = tlimit-min*60;
	
	document.getElementById('dt-minutes').innerHTML = min;
	document.getElementById('dt-seconds').innerHTML = sec;
	
	if(tlimit > 0)
	{
		setTimeout("doClock()", 1000);
	}
	else
	{
		var ele = document.getElementById('darni-test');
		var inp = ele.getElementsByTagName('input');
		for(i = 0; i < inp.length; i++)
	  	{
	  		if(inp[i].type == 'checkbox')
	  		{
				inp[i].setAttribute('disabled','disabled');
				inp[i].disabled = true;
			}	    		
	  	}
		
		if( checkDarniTest() )
		{
			document.getElementById('darni-test').submit();	
		}
	}
}

function checkDarniTest()
{

	if(document.getElementById("dt-email").value.length < 5)
	{
		document.getElementById("dt-email").style.border="1px solid #cc0000";
		document.location = "#dt-email";
		document.getElementById("dt-email").focus();
		return false;
	}
	else
	{
		document.getElementById("dt-email").style.border="1px solid #CECECE";
	}
	
	if(document.getElementById("dt-name").value.length < 2)
	{
		document.getElementById("dt-name").style.border="1px solid #cc0000";
		document.location = "#dt-name";
		document.getElementById("dt-name").focus();
		return false;
	}
	else
	{
		document.getElementById("dt-name").style.border="1px solid #CECECE";
	}
	
	return true;
}