.box {
width: 700px;
height: 250px;
margin: 0;
padding: 90px 50px 0 50px;
background: url("hintergrund-schalflachen.png") no-repeat;
}

.box table {
background-image: url("hintergrund-text-weiss.png");
}

.knopf a {
display: block;
border: 1px solid blue;
font-size: 12px;
width: 160px;
height: 30px;
background-image: url("hintergrund-text-weiss.png");
padding: 15px 0 0 0;
margin: 5px;
text-align: center;
text-decoration: none;
float: left;
}

.knopf a:visited {
border: 1px solid #0c673f;
}

.knopf a:hover {
background-image: url("hintergrund-text-weiss.png");
border: 1px solid red;
}