#iInput::-webkit-input-placeholder {color: blue;}
#iInput:-moz-placeholder {color: blue;}
#iInput:-ms-input-placeholder {color: blue;}
<input id='iInput' placeholder='lol'/> <br>
<textarea id='iInput' placeholder='lol'></textarea>
#iInput::-webkit-input-placeholder {color: blue;}
#iInput:-moz-placeholder {color: blue;}
#iInput:-ms-input-placeholder {color: blue;}
<input id='iInput' placeholder='lol'/> <br>
<textarea id='iInput' placeholder='lol'></textarea>