function expandCollapse(id) {
	var m1 = document.getElementById('M1');
	var m2 = document.getElementById('M2');
	var t = document.getElementById('Themes');
    
	if(id == "M1")
	{
		m1.style.visibility = "visible" ;
		m2.style.visibility = "hidden" ;
		t.style.visibility = "hidden" ;
	}
	else
	{
		m2.style.visibility = "visible" ;
		m1.style.visibility = "hidden" ;
		t.style.visibility = "hidden" ;
	}
}

function expandThemes() {
	var t = document.getElementById('Themes');
    
	t.style.visibility = "visible" ;
}

function hiddenCollapse() {
	var m1 = document.getElementById('M1');
	var m2 = document.getElementById('M2');
	var t = document.getElementById('Themes');
    
	m1.style.visibility = "hidden" ;
	m2.style.visibility = "hidden" ;
	t.style.visibility = "hidden" ;
}

function getWindowHeight() {
    var windowHeight=0;
    if (typeof(window.innerHeight) == 'number')
	{
        windowHeight = window.innerHeight;
    }
    else 
	{
    	if (document.documentElement.clientHeight)
	 	{
        	windowHeight = document.documentElement.clientHeight;
   		}
    	else
		{
     		if (document.body.clientHeight)
	 		{
         		windowHeight = document.body.clientHeight;
      		}
     	}
    }
    return windowHeight;
}

function modifMarges(bloc)
{
	var NavName = navigator.appName;
	var NavVers = navigator.appVersion;
	
	var p = document.getElementById(bloc);
	
	var hauteur = getWindowHeight();
	var margeH = hauteur-700;
	if(margeH > 0)
	{
		var demiMargeH = Math.floor(margeH/2);
		p.style.marginTop = demiMargeH+"px";
	}
}