about the puzzle, I don't want to spoil the answer right away, but you can scroll down the page and take a look at W3r3 W0lf 's comment. Also, the dark forest quest is not completed yet, it will be completed when the werewolf questline is finished.
Translation:
关于这个难题，我不想立即破坏答案，但您可以向下滚动页面并查看 W3r3 W0lf 的评论。
另外，黑暗森林任务还没有完成，狼人任务线完成后就会完成。