body>* {display: none !important;}
body {background-image: url(https://shoptet.tomashlad.eu/user/documents/modul/rek.jpg);background-size:cover;}
body:before {content: "Probíhá údržba webu...";display:block;position: absolute;top: 50%; left: 50%;transform: translate(-50%,-50%);font-size: 42px;font-weight:600;}

@media only screen and (max-width: 767px) {
	body:before {font-size:  15px;width: 90%;}
}