function ts(value)
{
    var d = document,cEl = null,cSize,nSize,bodyElement,sacle;
       
    bodyElement = document.getElementsByTagName('body')[0];
    cSize = (bodyElement.style.fontSize).replace('%', '');
    
    if (cSize>63 && cSize<103)
    {
        switch (value)
        {
        case '+':
            scale = (10);
            break;
        case '-':
            scale = (-10);
            break;
        }
        nSize = (parseFloat(cSize) + scale) + '%';
    }
    else if (cSize == 103)
    {
        switch (value)
        {
        case '+':
            scale = (0);
            break;
        case '-':
            scale = (-10);
            break;
        }
        nSize = (parseFloat(cSize) + scale) + '%';
    }
    else if (cSize == 63)
    {
        switch (value)
        {
        case '+':
            scale = (10);
            break;
        case '-':
            scale = (0);
            break;
        }
        nSize = (parseFloat(cSize) + scale) + '%';
    }
        
    if ( !(d.getElementById('body'))) cEl = d.getElementsByTagName('body')[0];
        cEl.style.fontSize = nSize;

}