.rinkai a {
    width: 1200px;
    height: 200px;
    background: url("rinkai.jpg") no-repeat;
    display: block;
    text-indent: -9999px;
}
.rinkai a:hover {
    background-position: 0 -200px;
}

.vse a {
    width: 1200px;
    height: 200px;
    background: url("vse.jpg") no-repeat;
    display: block;
    text-indent: -9999px;
}
.vse a:hover {
    background-position: 0 -200px;
}

.sagami a {
    width: 1200px;
    height: 200px;
    background: url("Sagami.jpg") no-repeat;
    display: block;
    text-indent: -9999px;
}
.sagami a:hover {
    background-position: 0 -200px;
}

.materials a {
    width: 1200px;
    height: 200px;
    background: url("materials.jpg") no-repeat;
    display: block;
    text-indent: -9999px;
}
.materials a:hover {
    background-position: 0 -200px;
}

.download a {
    width: 300px;
    height: 100px;
    background: url("Download_rinkai.jpg") no-repeat;
    display: block;
    text-indent: -9999px;
}
.download a:hover {
    background-position: 0 -100px;
}