IE11placeholder文字无法置灰

input:-ms-input-placeholder, textarea:-ms-input-placeholder{ //ie10+ input和textarea
color: #999 !important;
}

input::-webkit-input-placeholder {
color: #999 !important;
}

input:-moz-placeholder {
color: #999 !important;
}
input::-moz-placeholder {
color: #999 !important;
}

input:-ms-input-placeholder {
color: #999 !important;
}