HTML elements are not the same width

Question

I am coding a MVC 5 view, and have a question in regards to the width of two view elements.

Here is a picture of the view:

Here is my code:

<div class="form-group">
    @Html.LabelFor(model => model.width, htmlAttributes: new { @class = "control-label col-md-2" })
    <div class="col-md-10">
        <div class="input-group spinner">
            @Html.EditorFor(model => model.width, new { htmlAttributes = new { @class = "form-control" } })
            <div class="input-group-btn-vertical">
                <button type="button" id="inputSpinnerUpWidth" class="btn btn-default"><i class="fa fa-caret-up"></i></button>
                <button type="button" id="inputSpinnerDownWidth" class="btn btn-default"><i class="fa fa-caret-down"></i></button>
            </div>
        </div>
        @Html.ValidationMessage("assetwidth")
    </div>
</div>

<div class="form-group">
    @Html.LabelFor(model => model.height, htmlAttributes: new { @class = "control-label col-md-2" })
    <div class="col-md-10">
        <div class="input-group spinner">
            @Html.EditorFor(model => model.height, new { htmlAttributes = new { @class = "form-control" } })
            <div class="input-group-btn-vertical">
                <button type="button" id="inputSpinnerUpHeight" class="btn btn-default"><i class="fa fa-caret-up"></i></button>
                <button type="button" id="inputSpinnerDownHeight" class="btn btn-default"><i class="fa fa-caret-down"></i></button>
            </div>
        </div>
        @Html.ValidationMessage("assetheight")
    </div>
</div>

The Width and Height elements are not the same width as the other form controls. How can I get the two input-group spinner elements to be the same width as the other form controls?

Here is the view code for the "Asset name" HTML element:

<div class="form-group">
    @Html.LabelFor(model => model.name, htmlAttributes: new { @class = "control-label col-md-2" })
    <div class="col-md-10">
        @Html.EditorFor(model => model.name, new { htmlAttributes = new { @class = "form-control" } })
        @Html.ValidationMessageFor(model => model.name, "", new { @class = "text-danger" })
    </div>
</div>

Thanks in advance.

EDIT

Here is the spinner css code:

.spinner input {
  text-align: right;
}
.input-group-btn-vertical {
  position: relative;
  white-space: nowrap;
  vertical-align: middle;
  display: table-cell;
}
.input-group-btn-vertical > .btn {
  display: block;
  float: none;
  width: 100%;
  max-width: 100%;
  padding: 8px;
  margin-left: -1px;
  position: relative;
  border-radius: 0;
}
.input-group-btn-vertical > .btn:first-child {
  border-top-right-radius: 4px;
}
.input-group-btn-vertical > .btn:last-child {
  margin-top: -2px;
  border-bottom-right-radius: 4px;
}
.input-group-btn-vertical i{
  position: absolute;
  top: 0;
  left: 4px;
}

In the Site.css, there is the following code:

input,
select,
textarea {
    max-width: 280px;
}

How can I add the input-group spinner to the above CSS?

I have tried the following:

input,
select,
spinner,
textarea {
    max-width: 280px;
}

Answer 1

Add this to your CSS

.spinner {
  width: 280px;
}