// hlavní menu

// image preloader
image1 = new Image();
image1.src = 'images/btn_uvod_over.jpg';

image2 = new Image();
image2.src = 'images/btn_reference_over.jpg';

image3 = new Image();
image3.src = 'images/btn_foto_over.jpg';

image4 = new Image();
image4.src = 'images/btn_portfolio_over.jpg';

image5 = new Image();
image5.src = 'images/btn_cenik_over.jpg';

image6 = new Image();
image6.src = 'images/btn_kontakt_over.jpg';

image7 = new Image();
image7.src = 'images/btn_certifikaty_over.jpg';

image8 = new Image();
image8.src = 'images/banner_platino_over.jpg';

image9 = new Image();
image9.src = 'images/banner_doprava_over.jpg';

image10 = new Image();
image10.src = 'images/banner_okna_over.jpg';

//change function
function changeimg(filename, imagename){
  	document.images[imagename].src = filename;
}
function checknewsform(){ 
    var frmTerm = document.getElementById('newsletters');
    var emailExp = /^[\w\-\.\+]+\@[a-zA-Z0-9\.\-]+\.[a-zA-z0-9]{2,4}$/;
        if(frmTerm.email.value.match(emailExp)){
                frmTerm.submit();
                return true;
        }else{
                alert('Zkontrolujte zadaný email.\nNeodpovídá tvaru emailu.');
                return false;
        }
}