Bootstrap justified nav not working - css

Question

I need to make a responsive navbar and I wanted to use something like this
http://getbootstrap.com/examples/justified-nav/
It is supposed to load like this
And when min-width reaches 768px it changes to this
But in my project it loads like this and it doesn't change at all
I used the styles from the example page (http://getbootstrap.com/examples/justified-nav/justified-nav.css)
This is what's inside the body of my html
<header>
<img id="logoss" src="images/logo.png">
<ul class="nav nav-justified">
<li class="active">Empresa</li>
<li class="divider-vertical"></li>
<li>Medios</li>
<li class="divider-vertical"></li>
<li>Acci&oacuten</li>
<li class="divider-vertical"></li>
<li>Herramientas</li>
<li class="divider-vertical"></li>
<li>Staff-Sumate</li>
<li class="divider-vertical"></li>
<li>Contacto</li>
</ul></header>
and all of my style.css
* {
margin:0;
padding:0;
}
body {
background-color:#3b8476;
}
header {
height:200px;
margin: 0 auto;
max-width: 80%;
background-color:#fff;
background: #dddddd; /* Old browsers */
background: -moz-linear-gradient(top, #dddddd 0%, #ffffff 16%, #ffffff 82%, #dddddd 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#dddddd), color-stop(16%,#ffffff), color-stop(82%,#ffffff), color-stop(100%,#dddddd)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, #dddddd 0%,#ffffff 16%,#ffffff 82%,#dddddd 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, #dddddd 0%,#ffffff 16%,#ffffff 82%,#dddddd 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, #dddddd 0%,#ffffff 16%,#ffffff 82%,#dddddd 100%); /* IE10+ */
background: linear-gradient(to bottom, #dddddd 0%,#ffffff 16%,#ffffff 82%,#dddddd 100%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#dddddd', endColorstr='#dddddd',GradientType=0 ); /* IE6-9 */
}
#logoss {
height:8em;
width:8em;
display:inline-block;
margin:2em;
}
/* from justified navbar example */
.nav-justified {
background-color: #eee;
border-radius: 5px;
border: 1px solid #ccc;
}
.nav-justified > li > a {
margin-bottom: 0;
padding-top: 15px;
padding-bottom: 15px;
color: #777;
font-weight: bold;
text-align: center;
border-bottom: 1px solid #d5d5d5;
background-color: #e5e5e5; /* Old browsers */
background-repeat: repeat-x; /* Repeat the gradient */
background-image: -moz-linear-gradient(top, #f5f5f5 0%, #e5e5e5 100%); /* FF3.6+ */
background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#f5f5f5), color-stop(100%,#e5e5e5)); /* Chrome,Safari4+ */
background-image: -webkit-linear-gradient(top, #f5f5f5 0%,#e5e5e5 100%); /* Chrome 10+,Safari 5.1+ */
background-image: -o-linear-gradient(top, #f5f5f5 0%,#e5e5e5 100%); /* Opera 11.10+ */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#f5f5f5', endColorstr='#e5e5e5',GradientType=0 ); /* IE6-9 */
background-image: linear-gradient(top, #f5f5f5 0%,#e5e5e5 100%); /* W3C */
}
.nav-justified > .active > a,
.nav-justified > .active > a:hover,
.nav-justified > .active > a:focus {
background-color: #ddd;
background-image: none;
box-shadow: inset 0 3px 7px rgba(0,0,0,.15);
}
.nav-justified > li:first-child > a {
border-radius: 5px 5px 0 0;
}
.nav-justified > li:last-child > a {
border-bottom: 0;
border-radius: 0 0 5px 5px;
}
#media (min-width: 768px) {
.nav-justified {
max-height: 52px;
}
.nav-justified > li > a {
border-left: 1px solid #fff;
border-right: 1px solid #d5d5d5;
}
.nav-justified > li:first-child > a {
border-left: 0;
border-radius: 5px 0 0 5px;
}
.nav-justified > li:last-child > a {
border-radius: 0 5px 5px 0;
border-right: 0;
}
}

Answer 1

There was something wrong with the version of bootstrap I'm using, I updated the file and worked just fine, thanks to everyone who tried to help