JSFiddle - React, Tailwind, and code Playground
HTML
<div class="form-group outer">
<div class="col-xs-10 vcenter">
<div class="span7 text-center">
<form id="formid" method="get">
<label for="platform" class="control-label">Enter Code, IMEI or Phone Number:</label><br />
<input type="text" class="form-control" name="filtername" placeholder="Please Enter Code" />
<input id="btngo" class="btn btn-success" value="GO" />
</form>
@using (Html.BeginForm("Index", "Home", FormMethod.Get))
{
<p>
@Html.TextBox("filtername")
<input type="submit" class="btn btn-success" value="GO" />
</p>
}
</div>
</div>
CSS
.outer {
display:table;height:300px;text-align:center;
}
.vcenter {display:table-cell;
vertical-align:middle;
}