When we start this challenge, we see a comment in the code that says
<!-- No more information leaks!! Not even Google will find it this time... -->
This gives the clue that it has something to do with Search Engines and indexing. This refers to robots.txt which provides instructions to web crawlers on which parts of a website it should not access.
By going to /robots.txt we see
It tries to disallow /s3cr3t, By going to it we see
in which we find the password for natas4
Thus the password is QryZXc2e0zahULdHrtHxzyYkj59kUxLQ
