tab.css

.tabs {
  position: relative;
  width: 680px;
  min-height: 350px;
  margin: 1.2em auto 1em auto;
}
.tabs .tab {
  display: inline-block;
  margin: 0 -1px;
}
.tabs .tab label {
  position: relative;
  margin: 0;
  background: #dadada;
  border: 1px solid #ccc;
  border-bottom: none;
  -moz-border-radius:.5em;
  -webkit-border-radius:.5em;
  -khtml-border-radius:.5em;
  border-radius:.5em;
  padding: .5em .6em;
  font-weight: 700;
  cursor: pointer;
}
.tabs .tab [type=radio] {
  display: none;
}
.tabs .tab [type=radio]:checked ~ label {
  background: #d8fbda;
  border-bottom: 1px solid white;
  text-decoration: underline;
}
.tabs .tab [type=radio]:checked ~ label ~ .content {
  display: block;
}
.tabs .tab .content {
  display:none;
  position: absolute;
  top: 1.7em;
  left: 0;
  right: 0;
  background: #fdfdee;
  border: 1px solid #ccc;
  padding: .3em .8em;
}