How to add gradient background in bootstrap navbar

.navbar-default {
background-image: -webkit-linear-gradient(top, #ffffff 0%, #dfdfdf 100%);
background-image: linear-gradient(to bottom, #ffffff 0%, #dfdfdf 100%);
background-repeat: repeat-x;
filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#ffffffff', endColorstr='#ffdfdfdf', GradientType=0);
}