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<div class="container-fluid">
    
    <h1>input type="file"</h1>
    
    <form class="form-horizontal well">
        
        <div class="control-group">
            <label class="control-label" for="id_images">accept images (jpg, gif, png, bmp):</label>
            <div class="controls">
                <input type="file" class="input-xlarge" id="id_images" name="images" accept="image/jpg,image/jpeg,image/gif,image/png,image/bmp">
            </div>
        </div>
        
        <div class="control-group">
            <label class="control-label" for="id_text">accept text formats (pdf, zip, txt, doc):</label>
            <div class="controls">
                <input type="file" class="input-xlarge" id="id_text" name="text" accept="application/pdf,application/zip,text/plain,application/msword,    
application/vnd.openxmlformats-officedocument.wordprocessingml.document">
            </div>
        </div>
        
    </form>
    
</div>

External resources loaded into this fiddle: