bootstrap modal框出现蒙层,无法点击modal框内容

 <header>
        <nav class="navbar navbar-inverse navbar-fixed-top">
            <div class="container">
                <div class="navb-header">
                    <div class="navbar-brand">Personal resume</div>
                    <button type="button" class="navbar-toggle" data-toggle="collapse" data-target="#divNav">
                        <span class="icon-bar"></span>
                        <span class="icon-bar"></span>
                        <span class="icon-bar"></span>
                    </button>
                </div>
                <div id="divNav" class="collapse navbar-collapse">
                    <ul class="nav navbar-nav navbar-right">
                        <li>
                            <button type="button" class="btn btn-success navbar-btn" data-toggle="modal" data-target="#divModal" title="Print">Print</button>
                            <div id="divModal" class="modal">
                                <div class="modal-dialog">
                                    <div class="modal-content">
                                        <div class="modal-header">
                                            <button type="button" class="close" data-dismiss="modal"><span>&times;</span></button>
                                            <h4 class="modal-title">Print Resume</h4>
                                        </div>
                                        <div class="modal-body">
                                            Print Preview or Print Config
                                        </div>
                                        <div class="modal-footer">
                                            <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
                                            <button type="button" class="btn btn-default">Print</button>
                                        </div>
                                    </div>
                                </div>
                            </div>
                        </li>
                    </ul>
                </div>
            </div>
        </nav>
    </header>

把model的z-index设置的高一点

.modal-backdrop{z-index:0;}