Remove border of navbar-left and right bootstrap on mobile menu - css

Question

Hi am working on my navbar. When the navbar is in mobile view when I click and open the menu above and below the form input there looks to be like border-bottom
Like here
I am unable to find away to hide those two lines.
Question On when in mobile view how is it possible to remove / disable
those border-bottom above and below form input
Codepen Example
body {
background: url('../images/bg.png');
}
h1,
h2,
h3,
h4,
h5,
h6 {
margin: 0;
}
hr {
border-top: 10px solid #444444;
position: fixed;
}
.navbar-left {
border-bottom: 0;
border-top: 0;
}
.navbar-form {
border-bottom: 0;
border-top: 0;
}
.page-wrapper {
margin-top: 40px;
}
#media (min-width: 768px) {
.custom-nav .navbar-nav > li > a {
padding-top: 15px;
padding-bottom: 15px;
min-width: 150px;
}
}
.custom-nav {
margin-bottom: 0;
background: #333333;
border: none;
border-radius: 0;
}
.custom-nav .navbar-brand {
color: #FFFFFF;
}
.custom-nav .navbar-brand:hover {
color: #FFFFFF;
}
.custom-nav .navbar-nav > .active > a,
.custom-nav .navbar-nav > .active > a:hover,
.custom-nav .navbar-nav > .active > a:focus {
background: none;
color: #ffffff;
}
.custom-nav .navbar-nav > li > a {
color: #ffffff;
font-size: 14.5px;
text-align: center;
}
.custom-nav .navbar-nav > li > a.home {
border-top: 2px solid #AC3931;
}
.custom-nav .navbar-nav > li > a.home:hover,
.custom-nav .navbar-nav > li > a.home:focus {
background-color: #AC3931;
}
.custom-nav .navbar-nav > li > a.forum {
border-top: 2px solid #F6AE2D;
}
.custom-nav .navbar-nav > li > a.forum:hover,
.custom-nav .navbar-nav > li > a.forum:focus {
background-color: #F6AE2D;
}
.custom-nav .navbar-nav > li > a.blog {
border-top: 2px solid #3B910D;
}
.custom-nav .navbar-nav > li > a.blog:hover,
.custom-nav .navbar-nav > li > a.blog:focus {
background-color: #3B910D;
}
.custom-nav .navbar-nav > li > a.codeigniter {
border-top: 2px solid #2868B7;
}
.custom-nav .navbar-nav > li > a.codeigniter:hover,
.custom-nav .navbar-nav > li > a.codeigniter:focus {
background-color: #2868B7;
}
#media only screen and (min-width: 1040px) {
.custom-nav .navbar-collapse {
padding-left: 0;
padding-right: 0;
}
}
#media only screen and (max-width: 1040px) {
.custom-nav .navbar-collapse .navbar-nav > li > a {
text-align: left;
}
.custom-nav .navbar-collapse .navbar-nav > li > a.home {
border-top: none;
border-left: 2px solid #AC3931;
}
.custom-nav .navbar-collapse .navbar-nav > li > a.forum {
border-top: none;
border-left: 2px solid #F6AE2D;
}
.custom-nav .navbar-collapse .navbar-nav > li > a.blog {
border-top: none;
border-left: 2px solid #3B910D;
}
.custom-nav .navbar-collapse .navbar-nav > li > a.codeigniter {
border-top: none;
border-left: 2px solid #2868B7;
}
}
.page {
background: #EEEEEE;
/*box-shadow: 6px 6px 0px #989898, 12px 12px 0px #6B6666;*/
min-height: 500px;
padding: 20px;
}
.module {
background: #fff;
padding: 20px;
margin-bottom: 40px;
box-shadow: 0 0 5px rgba(0, 0, 0, 0.1);
}
.module .module-info {
color: #999;
font-size: 0.8em;
letter-spacing: 0.2em;
text-transform: uppercase;
font-family: 'source code pro';
}
.module .module-title {
font-size: 2.2em;
color: #000;
font-weight: bold;
display: block;
margin-bottom: 10px;
}
HTML
<div class="container">
<nav class="navbar navbar-inverse custom-nav">
<!-- Brand and toggle get grouped for better mobile display -->
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1" aria-expanded="false">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
</div>
<!-- Collect the nav links, forms, and other content for toggling -->
<div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
<ul class="nav navbar-nav">
<li ><a class="home" href="#">Home</a></li>
<li><a class="forum" href="#">Forum</a></li>
<li><a class="blog" href="#">Blog</a></li>
<li class="dropdown">
CodeIgniter <span class="caret"></span>
<ul class="dropdown-menu">
<li>Action</li>
<li>Another action</li>
<li>Something else here</li>
<li role="separator" class="divider"></li>
<li>Separated link</li>
</ul>
</li>
</ul>
<form class="navbar-form navbar-right">
<span class="fa fa-search"></span>
<input type="text" class="form-control" placeholder="Search">
</form>
</div><!-- /.navbar-collapse -->
</nav>
</div><!-- /.container-->

Answer 1

Put box-shadow: none; to <form class="navbar-form navbar-right"> and the problem will be solved.
Code:
form.navbar-form.navbar-right {
box-shadow: none;
}
Codepen: → here.

Answer 2

try the below code
#media (max-width: 768px){
.navbar-form{
-webkit-box-shadow:none;
box-shadow:none;
}
}

Answer 3

Thanks to every ones solution
SOLVED
When I just added box shadow none on it's own it still showed lines but darker
There for I have had to add border-top 0 and
border-bottom 0 and it worked
.navbar-form {
box-shadow: none;
border-top: 0;
border-bottom: 0;
}
Problem Solved.