// Specify affected tags. Add or remove from list:
var tgs = new Array('div', 'td', 'tr');

// Specify spectrum of different font sizes:
var szs = new Array('xx-small', 'x-small', 'small', 'medium', 'large', 'x-large', 'xx-large');
var startSz = 2;

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

	sz += inc;
	if ( sz < 0 ) sz = 0;
	if ( sz > 6 ) sz = 6;
	startSz = sz;

	if ( !( cEl = d.getElementById( trgt ) ) ) cEl = d.getElementsByTagName( trgt )[ 0 ];

	cEl.style.fontSize = szs[ sz ];

	for ( i = 0 ; i < tgs.length ; i++ )
	{
		cTags = cEl.getElementsByTagName( tgs[ i ] );
		for ( j = 0 ; j < cTags.length ; j++ ) cTags[ j ].style.fontSize = szs[ sz ];
	}
}