Bootstrap（八）：组件--图标

1.样式

2使用

    <div class="form-group">
        <div class="col-sm-10 col-xs-3">
            <button type="button" class="btn btn-default" >
                  <span class="glyphicon glyphicon-send" ></span> 飞机
            </button>
            
            <button type="button" class="btn btn-default" >
                   <span class="glyphicon glyphicon-star" ></span> Star
            </button>
            
            <button type="button" class="btn btn-default" >
                   <span class="glyphicon glyphicon-grain" ></span> 小草
            </button>
            
            <button type="button" class="btn btn-default" >
                   <span class="glyphicon glyphicon-tree-deciduous" ></span> 大树
            </button>
        </div>
    </div>