function show( id ) {
    var elem = document.getElementById( id );
    if( supportsOpacity( elem )) {       
        setOpacity( elem, 0 );        
        elem.style.display = "block";        
        fadeIn( id );
    } else {       
        elem.style.display = "block";
    }
}
function hide( id ) {
    var elem = document.getElementById( id );
    elem.style.display="none";
}
function supportsOpacity( el ) {
    if ( el.style.opacity != undefined ) return true;
    if( el.style.MozOpacity != undefined ) return true;
    if ( el.style.filter != undefined ) return true;
    return false;
}
function setOpacity( el, opaciLevel ) {
    if ( el.style.opacity != undefined ) {
        el.style.opacity = opaciLevel;
    } else if( el.style.MozOpacity != undefined ) {
        el.style.MozOpacity = opaciLevel;
    } else if ( el.style.filter != undefined ) {
        var oplvl = Math.round(opaciLevel*100);
        el.style.filter="alpha(opacity=" + oplvl + ")";
    }
}
function fadeIn( id, currentOpacity ) {
    var counterLimit = 20;
    var el = document.getElementById( id );
    if( !currentOpacity ) {
        currentOpacity = 1;
    }
    if( currentOpacity > counterLimit ) {
        return;
    }
    setOpacity( el, ( currentOpacity/counterLimit ) );
    currentOpacity++;
    var func = "fadeIn( '" + id + "', " + currentOpacity + ")";
    window.setTimeout( func, 50);
}