Grid: Header row colors

How can grid header rows be custom colored in the valo theme? Something along these lines:

.v-grid-header .v-grid-row.myheaderrow .v-grid-cell { // what goes here? } css like this for buttons:

.v-button-orange { @include valo-button-style($background-color: #FFEDDB); } preserves the valo gradient but allows selection of the base color. Is there an equivalent for grid header rows?