CSS实现圆角矩形

<div class="col-xs-4">
        <div class="row">
            <div class="panel" style="position:relative;border:0.02rem solid #052841;border-radius:0.08rem;background-color: rgba(255, 255, 255, 0.0);">
                <span style="position:absolute;padding:0.06rem;border-style:solid;border-color: #005F79;border-width: 0.02rem 0 0 0.02rem;top:-0.02rem;left:-0.02rem;border-top-left-radius:0.08rem;"></span>
                <span style="position:absolute;padding:0.06rem;border-style:solid;border-color: #005F79;border-width: 0.02rem 0.02rem 0 0;top:-0.02rem;right:-0.02rem;border-top-right-radius:0.08rem;"></span>
                <span style="position:absolute;padding:0.06rem;border-style:solid;border-color: #005F79;border-width: 0 0 0.02rem 0.02rem;bottom:-0.02rem;left:-0.02rem;border-bottom-left-radius:0.08rem;"></span>
                <span style="position:absolute;padding:0.06rem;border-style:solid;border-color: #005F79;border-width: 0 0.02rem 0.02rem 0;bottom:-0.02rem;right:-0.02rem;border-bottom-right-radius:0.08rem;"></span>
                <div class="panel-body">
                    <div class="panel-body-chart" id="chart-Product" style="height:3.34rem;">
                        @Html.LocText("loc_loading", "Loading...")
                    </div>
                </div>
            </div>
        </div>
    </div>