need some help centering 3 things next to each other in html/css (more complicated than just 3 images)

This is not a duplicate question, so please read the whole post through! I've got several elements that I am trying to group together and then center them on page like so:

                                         |
                                         |
              Username:                  |                 
              ________________           |                 IMG 1
              Password:                  |                 
              ________________           |                 IMG 2
                  login                  |
                                         |
                                         |

I don't want Username and password centered, I still want to those to be at the very left side of the input boxes.

Right now it looks something like this:

                                         |
 Username                              IM|G 2  
                                         |                 
         _______________                 |                 IMG 1
         _______________             Pass|word:                 
                                         |                 
                  login                  |
                                         |
                                         |

I've got IMG 1, the login button and the vertical line in a good spot but the form is just all over the place. I've tried playing around with a lot of different things to get the rest of the login form and IMG 2 in the right spot but I am stuck. Here is the basic layout of my html file:

<div id="center-wrapper">
    <div id="img1">
        <img src="img1.png" />
    </div>
    <br>
    <div id="img2">
        <img src="img2.png" />
    </div>

    <div id="line"></div>

    <form id="form-wrapper" action="/login/" method="post" style="width:40%;">
    {% csrf_token %}
    {% for field in form %}
    <br>
        {% if field.errors %}
            <div class="form-group has-error">
                <label class="col-sm-2 control-label" for="id_{{ field.name }}">
                {{ field.label }}</label>
                <div class="col-sm-10">
                    {{ field|attr:"class:form-control" }}
                    <span class="help-block">
                        {% for error in  field.errors %}{{ error }}{% endfor %}
                    </span>
                </div>
            </div>
        {% else %}
            <div class="form-group">
                <label class="col-sm-2 control-label" for="id_{{ field.name }}">{{ field.label }}</label>
                <div class="col-sm-10">
                    {{ field|attr:"class:form-control" }}
                    {% if field.help_text %}
                        <p class="help-block"><small>{{ field.help_text }}</small></p>
                    {% endif %}
                </div>
            </div>
        {% endif %}
        <br>
    {% endfor %}
    <div class="form-group">
        <div class="col-sm-offset-2 col-sm-10">
            <br>
            <button type="submit" class="btn btn-primary" value="Log In">{% trans "Log In" %}</button><br>
            <br>Don't have an account? <a href="/signup/">Sign Up</a>
        </div>
    </div>
    </form>
</div>

My button is inside my form so I am not sure why that one is being centered properly and the rest of the form is not. Also, the <br> is not putting IMG 2 under IMG 1. My CSS is this:

#center-wrapper {
    text-align: center;
    margin: auto;
    width: 60%;
    height: 100%;
}

#form-wrapper {
    width: 50%;
}

#img1 {
    height: 220px;
    width: 274px;
    background: none;
    z-index: 30;
    float: right;
    position: absolute;
    margin-top: 0;
}

#img2 {
    height: 85px;
    width: 274px;
    background: none;
    z-index: 30;
    float: right;
    position: absolute;
    margin-bottom: 0;
}

#line {
    height: 305px;
    width: 2px;
    background-color: #8a8a8a;
    top: 200px;
    left: 50%;
    z-index: 30;
    position: absolute;
}

I don't think my question is very hard, but I have been struggling over getting this format right for so long and I just want some suggestions! I am using Django forms, which are pretty tricky to format (formatting them with widget-tweaks), but I don't think that should matter for moving its position around.