单个view水平居中，垂直居中

.cc{
     
	width:100%;
	height:100%;
	display:flex;
	justify-content:center;
	align-items:center;
	font-size:35rpx;
	position: fixed;
}

 <view  class="cc">
        <span>暂无可用优惠券</span>
    </view>