var szs = new Array( 'x-small','small','medium','large','x-large','xx-large' );
var slh = new Array( '1.1','1.2','1.5','1.5','1.5','1.6' );
var startSz = 1;

function ts( inc ) {
	if (!document.getElementById) return
	var sz = startSz,i,j,cTags;

	sz += inc;
	if ( sz < 0 ) sz = 0;
	if ( sz > 4 ) sz = 4;
	startSz = sz;

	document.getElementById('contentblok').style.fontSize = szs[ sz ];
	document.getElementById('contentblok').style.lineHeight = slh[ sz ];
}