以下API从网络收集，若有侵权请联系删除
壁纸PC: https://img.xjh.me/random_img.php?type=bg&ctype=nature&return=302
壁纸移动端：https://img.xjh.me/random_img.php?type=bg&ctype=nature&return=302&device=mobile
https://source.unsplash.com/原文：https://www.cnblogs.com/a-hao/p/10999261.html