Creating SharePoint Visual Webpart with Bootstrap - visual-studio

Question

I am creating a responsive sharepoint visual webpart.
everything works fine and looks good but my mobile view is pretty much off.
the controls doesn't shrink to the lowest mobile size..
i tried many times but still i have the same issue..
<fieldset class="form-horizontal">
<div class="control-group">
<label class="control-label col-xs-8 col-md-3 " for="textinput">Name:
</label>
<div class="controls col-xs-8 col-md-7">
<asp:TextBox MaxLength="50" runat="server" ID="txtTitle" CssClass="form-control">
</asp:TextBox>
</div>
</div>
<div class="clearfix">
</div>
<!-- Select Basic -->
<div class="control-group">
<label class="control-label col-xs-8 col-md-3 " for="selectbasic">Ano:
</label>
<div class="controls col-xs-8 col-md-2">
<asp:DropDownList runat="server" ID="ddYear" CssClass="form-control">
</asp:DropDownList>
</div>
</div>
<div class="control-group">
<label class="control-label col-xs-8 col-md-3 " for="selectbasic">Mes:
</label>
<div class="controls col-xs-8 col-md-2">
<asp:DropDownList runat="server" ID="ddMonth" CssClass="form-control">
</asp:DropDownList>
</div>
</div>
<div class="clearfix">
</div>
<!-- Text input-->
<div class="control-group">
<label class="control-label col-xs-8 col-md-3 " for="textinput">Tema de Salud:
</label>
<div class="controls col-xs-8 col-md-7">
<asp:DropDownList runat="server" CssClass="form-control" ID="ddHealthTopic">
</asp:DropDownList>
</div>
</div>
<div class="clearfix">
</div>
<div class="control-group">
<label class="control-label col-xs-8 col-md-3 " for="textinput">Unidad administrativa:(por sus siglas en ingles entre paréntesis)
</label>
<div class="controls col-xs-8 col-md-7">
<asp:DropDownList runat="server" CssClass="form-control" ID="ddOrgUnit">
</asp:DropDownList>
</div>
</div>
</fieldset>
<br />
<div class=" col-xs-10 col-md-10">
<div class="input-group" >
<span class="input-group-btn">
<asp:Button CssClass="btn btn-primary" ToolTip="Buscar" runat="server" ID="btnSubmit" Text="Buscar" OnClick="btnSubmit_Click" />
</span>
</div>
</div>

Answer 1

Your code seems to be fine ....
Try to add (If its no there)
<meta name="viewport" content="width=device-width, initial-scale=1">
head section of your master page