#my-nav {
background: rgb(254,204,177); /* Old browsers */
background: -moz-linear-gradient(top, rgba(254,204,177,1) 0%, rgba(241,116,50,1) 34%, rgba(234,85,7,1) 61%, rgba(251,149,94,1) 100%); /* FF3.6-15 */
background: -webkit-linear-gradient(top, rgba(254,204,177,1) 0%,rgba(241,116,50,1) 34%,rgba(234,85,7,1) 61%,rgba(251,149,94,1) 100%); /* Chrome10-25,Safari5.1-6 */
background: linear-gradient(to bottom, rgba(254,204,177,1) 0%,rgba(241,116,50,1) 34%,rgba(234,85,7,1) 61%,rgba(251,149,94,1) 100%); /* W3C, IE10+, FF16+, Chrome26+, Opera12+, Safari7+ */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#feccb1', endColorstr='#fb955e',GradientType=0 ); /* IE6-9 */
border-radius: 7px;
}
#my-nav a {
color: #FFF;
}
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" rel="stylesheet"/>
<ul class="nav" id="my-nav">
<li class="nav-item">
<a class="nav-link active" href="#">ABOUT</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">BLOG</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">SOLUTIONS</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">BOOKS</a>
</li>
</ul>