.menu_button {
    width: 70px;
    height: 70px;
    display: inline-block;
    text-indent: -9999px;
}

.button-stand-alone {
    background: 50% 50% url("../pictures/products/nvr/stand_alone.jpg") no-repeat ;
    background-size: 75%;
}

.button-pc-based {
    background: 50% 50% url("../pictures/products/nvr/pc_based.jpg") no-repeat ;
    background-size: 70%;
}

.button-cms {
    background: 50% 50% url("../pictures/products/nvr/cms.jpg") no-repeat ;
    background-size: 70%;
}

.model-no{
    width: 230px;
}

th.photo{
    width: 130px;
}

td.photo {
    height: 110px;
}

td.photo img {
    max-width: 100px;
}