How to align your texbox accordingly same width?

Question

Hi teamm

 

I am trying to align my Textbox on my front using asp.net mvc, when i try to amend  input-group col-md-3 the width gets shifted each time to be exact with same textbox. Help me to improve my textbox to align the same with other texbox, see below my logic.

<div class="row">
                     <div class="input-group col-md-8.0 col-md-offset-6 col-sm-6 col-xs-6">
                         <div class="input-group pull-right">

                             @Html.TextBoxFor(m => m.Address, new { @class = "form-control", type = "text", id = " street address line 2", autofocus = "autofocus", placeholder = "Street Address Line 2", required = "required" })
                             <div class="input-group-append">
                                 <div class="input-group-text">

                                 </div>
                             </div>
                         </div>
                     </div>
                 </div>

<div class="row">
                     <label for="Address">Address</label>
                     <div class="input-group col-md-6.9 col-md-offset-6 col-sm-6 col-xs-6">
                         <div class="input-group pull-left">

                             @Html.TextBoxFor(m => m.Address, new { @class = "form-control", type = "text", id = " street address", autofocus = "autofocus", placeholder = "Street Address", required = "required" })
                             <div class="input-group-append">
                                 <div class="input-group-text">

                                 </div>
                             </div>

                         </div>

                     </div>
                 </div>