随手做了个暗色主题，大家可以参考下自己改，另外字体也是：
div#lrbk_title {background:gray!important;color:#ccc!important;}
.bb-item {color:#eee!important;font-size:1.1em!important;}
#gnContent { background:gray!important;}
body {margin:-20px!important; background:gray!important;}