gistfile1.txt

input, textarea {
  border: 1px solid #c6c6c6;
  border-top-color: #afafaf;
     -moz-border-radius: 2px;
       -o-border-radius: 2px;
  -webkit-border-radius: 2px;
          border-radius: 2px;
     -moz-box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.1);
       -o-box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.1);
  -webkit-box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.1);
          box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.1);
  color: #666;
  font: 13px/20px "Open Sans", "Helvetica Neuve", Helvetica, Arial, sans-serif;
  padding: 3px;
  position: relative;
}
input:required:after {
  color: #c00;
  content: "\002A"; /* * – Asterisk */
  font-size: 16px;
  position: absolute;
  right: 10px;
  top: 6px;
}
input:required:valid:after {
  color: green;
  content: "\2713"; /* ✓ – Checkmark */
  top: 3px;
}