.plus{
    background-image: url("plus.bmp");
    background-repeat: no-repeat;
    cursor: pointer;
    padding-left:12px;
    width: 10px;
    background-position: left;
}

.minus{
    background-image: url("minus.bmp");
    background-repeat: no-repeat;
    padding-left:12px;
    width:10px;
    cursor: pointer;
    background-position: left;
}