function agrandir() {
	
	var taille = document.getElementById('contenu').style.fontSize;
	
	if (taille == '10px') {
		document.getElementById('contenu').style.fontSize = '15px';
		p = document.getElementsByTagName('p');
		for (var i in p) {
        	if(p[i].className == 'spip') {
        		p[i].style.fontSize = '15px';
        	}
    	}
	}
	else if (taille == '15px') {
		document.getElementById('contenu').style.fontSize = '20px';
		p = document.getElementsByTagName('p');
		for (var i in p) {
        	if(p[i].className == 'spip') {
        		p[i].style.fontSize = '20px';
        	}
    	}
	}
	else {
		document.getElementById('contenu').style.fontSize = '10px';
		p = document.getElementsByTagName('p');
		for (var i in p) {
        	if(p[i].className == 'spip') {
        		p[i].style.fontSize = '10px';
        	}
		}
	}
}