source: pro-violet-viettel/sourcecode/application/modules/admin/views/reportAsistant/statistics.php

<div class="col-xs-12">
    <!-- PAGE CONTENT BEGINS -->
    <div class="col-xs-12 no-padding">
        <div class="widget-box no-border">
            <div class="widget-header widget-header-flat">
                <h4 class="lighter">
                    <i class="icon-signal"></i>
                    Biểu đồ người dùng do cộng tác viên giới thiệu
                </h4>

                <div class="widget-toolbar">
                    <a data-action="collapse" href="#">
                        <i class="icon-chevron-up"></i>
                    </a>
                </div>
            </div>
            
            <div class="widget-body">
                <div class="widget-main padding-4">
                    <div id="sales-charts"></div>
                </div><!-- /widget-main -->
            </div>
            
        </div><!-- /widget-box -->
    </div>

    <div class="clearfix"></div>
</div>