lex ui-flex-ver ui-flex-pack-center ui-flex-align-start">
                <div>左中</div>
                <div>左中</div>
            </div>
        </div>
    </div>
    <div class="demo-item">
        <p class="demo-desc">flex网格布局</p>
        <div class="demo-block">
            <ul class="ui-row-flex">
                <li class="ui-col ui-flex ui-flex-pack-start"><div>左</div><div>左</div></li>
                <li class="ui-col ui-flex ui-flex-pack-center"><div>中</div><div>中</div></li>
