dropdown wont drop on mobile screen - dropdown

Question

I have a dropdown which i need to keep the url intact on the parent so i put disable class, but when i open it on my mobile, it immediately goes to the url and it wont drop. Here's the code.
<div class="row">
<nav class="navbar navbar-default polo" role="navigation">
<div class="navbar-header">
<button type="button" class="navbar-toggle pull-left" data-toggle="collapse" data-target="#polo-nav">
<span class="sr-only">
</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
</div>
<div class="collapse navbar-collapse" id="polo-nav">
<ul class="nav navbar-nav">
<li class="dropdown">Accueil
<ul class="dropdown-menu">
<li>Activites</li>
<li>Infrastructures</li>
</ul>
</li>
<li class="dropdown">Tournois
<ul class="dropdown-menu">
<?php
$this->db->select('tou_name,id');
$this->db->where('trashed',0);
$this->db->from('tbl_tournament');
$query = $this->db->get();
foreach ($query->result() as $row)
{
?>
<li><?=$row->tou_name?></li>
<?php
}
?>
</ul>
</li>
<li><a class="polo-sub" href="<?=base_url()?>leclub.html">Le Club</a></li>
<li><a class="polo-sub" href="<?=base_url()?>schedule.html">Calendrier</a></li>
<li><a class="polo-sub" href="<?=base_url()?>polo/tarifs.html">Tarifs</a></li>
<li><a class="polo-sub" href="<?=base_url()?>polo/partenaires.html">Partenaires</a></li>
<li><a class="polo-sub" href="<?=base_url()?>actualities/actualities.html">Actualites</a></li>
<li><a class="polo-sub" href="<?=base_url()?>polo/contact.html">Contact</a></li>
</ul>
</div>
</nav>
</div>