Bootstrap : accordion-toggle doesn't work - asp.net-mvc

Question

I have a problem with my accodion-toggle . I put it in my code but it doesn't work my title stay in blue and with nothing near of my title.
This is my code :
#{string module_origine = "";
int step = 0;
}
<div class="accordion" id="accordion2">
#foreach (var test in Model)
{
if (module_origine != test.module)
{
module_origine = test.module;
step = step + 1;
<div class="accordion-group">
<div class="accordion-heading">
<a class="accordion-toggle" data-toggle="collapse" data-parent="#accordion2" href="#collapse_#step">
#Html.DisplayFor(ModelItem => test.module)
</a>
</div>
<div id="Collapse_#step" class="accordion-body collapse in">
<div class="accordion-inner ">
#foreach (var item in Model.Where(item => item.module == module_origine))
{
<form method="get" action="/#Html.DisplayFor(modelItem =>item.droit)">
<button type="submit" class="btn btn-primary" title="#Html.DisplayFor(ModelItem => item.description)">#Html.DisplayFor(modelItem => item.menunom)</button>
</form>
}
</div>
</div>
</div>
}
}
</div>
I don't understand why my class accordion-toggle doesn't work so I hope I can understand why and help me think you !

Answer 1

to get a panel it's easy just change that :
#{string module_origine = "";
int step = 0;
}
**<div class="panel-group" id="accordion">** //add that to create panel
#foreach (var test in Model)
{
if (module_origine != test.module)
{
module_origine = test.module;
step = step + 1;
<div class="panel panel-success ">
<div class="panel-heading">
<a class="accordion-toggle" data-toggle="collapse" data-parent="#accordion2" href="#collapse_#step">
#Html.DisplayFor(ModelItem => test.module)
</a>
</div>
<div id="Collapse_#step" class="accordion-body collapse in">
<div class="accordion-inner ">
#foreach (var item in Model.Where(item => item.module == module_origine))
{
<form method="get" action="/#Html.DisplayFor(modelItem =>item.droit)">
<button type="submit" class="btn btn-primary" title="#Html.DisplayFor(ModelItem => item.description)">#Html.DisplayFor(modelItem => item.menunom)</button>
</form>
}
</div>
</div>
</div>
}
}
</div>
I just remove the accordion content it's not wooking on my thing