span.filter span
{
  position: absolute;
  top: -0.1em;
  left: 0;
  width: 1em;
  text-align: center;
  display:inline-block;
}
    span.filter span:first-child {
        font-weight: bold;
        top: 0.2em;
    }

a.filter {
    display:block;
    width:50%;
}