body{
    width: 100%;
    height: 100%;
    background-image: url('https://cdn.wallpapersafari.com/59/78/6g3YeP.png');
    background-size: 100% 100%;
}

.highlight {
	background-color: yellow;
}

.error {
	background-color: lightcoral;
	border-color: red;
}