Change Bootstrap Hamburger Color Only on Collapse - css

Question

I'm using bootstrap to have a see-through nav when the page first opens, but as soon as the user scrolls down and the navbar collapses it changes to a white background.
I use this to make the background color change:
.top-nav-collapse {
background-color: #FFFFFF !important;
}
And I know from extensive Googling that this changes the color of the hamburger icon in general:
.navbar-default .navbar-toggle .icon-bar {
background-color: black;
}
However, I can't seem to get the color to change only on collapse. Here's my nav bar code:
<nav class="navbar navbar-fixed-top z-depth-1" role="navigation">
<div class="container-fluid">
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#bs-example-navbar-collapse-2">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a class="navbar-brand waves-effect waves-light pull-left" href="/"><%= image_tag 'Flame.png', style: "height: 100%"%></a>
</div> <!-- navbar-header -->
<div class="collapse navbar-collapse" id="bs-example-navbar-collapse-2">
<ul class="nav navbar-nav">
<li>Workouts <span class="sr-only">(current)</span></li>
<li><%= link_to 'Blog', posts_path, class:"waves-effect waves-light" %></li>
<li>Equipment</li>
<li>About Us</li>
</ul>
</div> <!-- navbar collapse -->
</div> <!-- container-fluid -->
</nav>
Can anyone shed any light on this?

Answer 1

Difficult to completely understand what you're asking, but I think you're just looking for this
.navbar-toggle.collapsed .icon-bar {
...
}
If you use as-is, you might need to !important any properties to override the Bootstrap defaults. Otherwise add any necessary specificity (i.e. #main-nav .navbar-toggle...) to the selector and you should be good.