<p style="font-size: 12px;color:#aaa;">版权引用：<a href="https://www.pexels.com/photo/avans-empty-stairs-stairway-456750/"><span style="font-size: 12px;color:black;">“ This photo is about stairs, stairway, university”</span> </a>由 <a href="https://www.pexels.com/@sjoerd-van-gurp-153621"><span style="font-size: 12px;color:black;">Sjoerd van Gurp </span></a> 授权许可 <span><a href="https://www.pexels.com/photo-license/" target="_blank" style="font-size: 12px;color:black;">Pexels License<img src="" style="display: inline-block;height: 16px;width: auto;"></a></span></p>