从主应用程序调用Web应用程序作为模式

I have on HR web application(localhost) mainly shows about the employee details,leaves,attendance everything.Now i want to add Time sheets entry in to that. For that already i have one opensource time sheet application developed in php and mysql. Just i want to invoke that application as modal window(not in maximize window) from my application and i need to pass the username of the main application to that second application. How can i do that? I used but it opens in full window..to get back to main application i have press Goback arrow.

Coding from main application:

<div class="col-lg-3 col-xs-6">
            <!-- small box -->
            <div class="info-box bg-yellow">
                <div class="inner">                 
                    <p>
                        Time sheet entry
                    </p>
                </div>
                <div class="icon">
                    <i class="ion ion-pie-graph"></i>
                </div>
                <a href="http://localhost/timesheet" class="small-box-footer" id="projectsLink">
                    Enter Now <i class="fa fa-arrow-circle-right"></i>
                </a>
            </div>
        </div>