I have used Twitter bootstrap on my website
Show loading
I followed your this article for progress bar. My progress bar works fine in webform(without master) but it doesnt work with content page (associted with mster page).
Content page code
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server">
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<div align="center">
<h1>Click the button to see the UpdateProgress!</h1>
<asp:Button ID="Button1" Text="Submit" runat="server" OnClick="Button1_Click" />
</div>
<asp:UpdateProgress ID="UpdateProgress1" runat="server" AssociatedUpdatePanelID="UpdatePanel1">
<ProgressTemplate>
<div class="modal">
<div class="center">
<img alt="" src="Images/Loading.gif" />
</div>
</div>
</ProgressTemplate>
</asp:UpdateProgress>
</ContentTemplate>
</asp:UpdatePanel>
</asp:Content>
Master page code(just included jquery and format of master page)
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css">
<!-- Optional theme -->
<!-- HTML5 shim and Respond.js for IE8 support of HTML5 elements and media queries -->
<!--[if lt IE 9]>
<script src="https://oss.maxcdn.com/html5shiv/3.7.2/html5shiv.min.js"></script>
<script src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script>
<![endif]-->
<!-- Latest compiled and minified JavaScript -->
<link href="Dashboard.css" rel="stylesheet" type="text/css" />
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js"></script>
<asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>
<asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server">
</asp:ContentPlaceHolder>