Edit in JSFiddle

.navigation li a span {
  display: none;   
}
.navigation li a.default, .navigation li a.active {
  display: block;
  float: left;
  margin: 20px 10px;
  width: 30px;
  height: 30px;
  -webkit-border-radius: 50%;
  -moz-border-radius: 50%;
  border-radius: 50%;
}

.navigation li a.default {
  background-color: #CACACA;
  box-shadow: 3px 3px 1px 1px #b9b9b9 inset;
  -webkit-box-shadow: 3px 3px 1px 1px #b9b9b9 inset;
  -moz-box-shadow: 3px 3px 1px 1px #b9b9b9 inset; 
}

.navigation li a.active {
  background: #85d945; /* Old browsers */
background: -moz-linear-gradient(top, #85d945 0%, #749f54 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#85d945), color-stop(100%,#749f54)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, #85d945 0%,#749f54 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, #85d945 0%,#749f54 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, #85d945 0%,#749f54 100%); /* IE10+ */
background: linear-gradient(top, #85d945 0%,#749f54 100%); /* W3C */
}


.navigation li a.default:hover {
  background-color: #B6B6B6;
  box-shadow: 3px 3px 1px 1px #B3B3B3 inset;
  -webkit-box-shadow: 3px 3px 1px 1px #B9B9B9 inset;
  -moz-box-shadow: 3px 3px 1px 1px #999 inset;    
}