th {
background-color: silver;
}
/* add hover effect for table rows */  
td.hovered {
background-color: lightskyblue;
}
th.sortable {
cursor: pointer;
padding-right: 23px;
background-repeat: no-repeat;
background-position: right center;
background-image: url('i/bg.gif');
}
th.sortable.sorted-asc,  th.sortable.sorted-desc {
color: white;
background-color: grey;
}
th.sortable.sorted-asc {
background-image: url('i/asc.gif');
}
th.sortable.sorted-desc {
background-image: url('i/desc.gif');
}
th.sortable:hover {
color: black;
background-color: yellow;
text-decoration: underline;
}