When your left sidebar gets position: fixed it is taken out of the flow of the page, which means the main content moves over to take its place.
A way to solve this is by adding a margin to the main content when you scroll. The margin should be equal to the amount of space occupied by the sidebar (33.333%).
You haven't tagged your question with jQuery, but if you are open to it here is a possible approach. You may have to tweak the numbers using media queries.
var onResize = function() {
$("body").css("padding-top", $(".navbar-fixed-top").height());
};
$(window).resize(onResize);
$(function() {
onResize();
});
$(document).ready(function() {
$('body').scrollspy({
target: '#mainNavbar',
offset: 10
});
});
$(window).scroll(function() {
var scroll = $(window).scrollTop();
if (scroll > 0) {
$("#content").addClass("fix");
} else {
$("#content").removeClass("fix");
}
});
html,
body {
height: 100%;
}
body {
padding-top: 50px;
}
.navbar-nav {
float: left;
margin: 0;
}
.navbar-nav>li {
float: left;
}
.navbar-nav>li>a {
padding-top: 15px;
padding-bottom: 15px;
}
.navbar-offset {
top: 0px;
}
.container {
background: #ccc;
}
.affix {
top: 20;
}
#content.fix {
margin-left: 33.333333%;
}
<!DOCTYPE html>
<html>
<head>
<title>Bootstrap Example</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.0/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
</head>
<body>
<nav class="navbar navbar-default navbar-fixed-top navbar-offset">
<div style="font-size:30px;margin-left:30px;">Title and logo here</div>
</nav>
<div class="container">
<div class="row">
<div class="col-lg-4 col-sm-4 col-md-4" style="background-color:gray;" data-spy="affix" data-offset-top="0">
<div style="height:280px;background-color:lightblue;margin-top:20px;"></div><br/>
<div id="mainNavbar">
<ul>
<li class="active"><a href="#divDesert">Desert</a></li>
<li><a href="#divLighthouse">Lighthouse</a></li>
<li><a href="#divTulips">Tulips</a></li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">
Animals <span class="caret"></span>
</a>
<ul class="dropdown-menu">
<li><a href="#divJellyfish">Jellyfish</a></li>
<li><a href="#divPenguins">Penguins</a></li>
</ul>
</li>
</ul>
</div>
</div>
<div class="col-lg-8 col-sm-8 col-md-8" id="content" style="background-color:lightblue;font-size:30px;">
<div id="divDesert">
<h1>Desert</h1>
<p>The Affix plugin allows an element to become affixed (locked) to an area on the page.</p>
</div>
<div id="divLighthouse">
<h1>Lighthouse</h1>
<p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit.</p>
</div>
<div id="divTulips">
<h1>Tulips</h1>
<p>Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium.</p>
</div>
<div id="divJellyfish">
<h1>Jellyfish</h1>
<p>But I must explain to you how all this mistaken idea of denouncing.</p>
</div>
<div id="divPenguins">
<h1>Penguins</h1>
<p>Li Europan lingues es membres del sam familie.</p>
</div>
</div>
</div>
</div>
</body>
</html>
