论坛如果换背景，就不要用那上面的了，质量太差，我换了一下：
body {
& when (@config-dark-mode = false) {
background: linear-gradient(90deg, #eff2f7 0%, 7.60286%, #edf0f9 15.2057%, 20.7513%, #ebf0f8 26.297%, 27.6386%, #ebf0f8 28.9803%, 38.2826%, #e7edf9 47.585%, 48.1216%, #e6ecfa 48.6583%, 53.1306%, #e4ecf9 57.6029%, 61.5385%, #e3eafa 65.4741%, 68.7835%, #deeafa 72.093%, 75.7603%, #dbe6f8 79.4275%, 82.8265%, #d8e5f8 86.2254%, 87.8354%, #d5e4f9 89.4454%, 91.8605%, #d2e2f9 94.2755%, 95.4383%, #d1e1f8 96.6011%, 98.3005%, #d0e0f7 100%) fixed;
}
& when (@config-dark-mode = true) {
background: linear-gradient(90deg, #23272e 0%, 7.60286%, #202431 15.2057%, 20.7513%, #1f252f 26.297%, 27.6386%, #1f252f 28.9803%, 38.2826%, #1c222f 47.585%, 48.1216%, #1b2130 48.6583%, 53.1306%, #1a222e 57.6029%, 61.5385%, #19202f 65.4741%, 68.7835%, #17202c 72.093%, 75.7603%, #161d28 79.4275%, 82.8265%, #151c26 86.2254%, 87.8354%, #131b26 89.4454%, 91.8605%, #121924 94.2755%, 95.4383%, #121822 96.6011%, 98.3005%, #111820 100%) fixed;
}
}
