Text input placeholders not displaying in IE and Firefox

Question

My text input placeholders refuse to display in IE and Firefox despite having used the -moz-placeholder attribute. This can be viewed on the contact page here if you are using F

Answer 1

::-webkit-input-placeholder { /* Chrome, Safari */
   color: #aaa;
   font-size: 18px;
}

:-moz-placeholder {           /* Firefox 18- */
   color: #aaa;
   font-size: 18px;
}

::-moz-placeholder {          /* Firefox 19+ */
  color: #aaa;
  font-size: 18px;
}

:-ms-input-placeholder {      /* Internet Explorer */
  color: #aaa;
  font-size: 18px;
}