I am not a lawyer and as such, do not have the training and experience required to be able to help you. However, I am an American citizen and that makes me responsible for making sure I myself do not break U.S. laws. In our legal system, ignorance of the law is no excuse. While being ignorant of the law can, in some cases, change the punishment you receive, it will not excuse you from breaking the law entirely.
This is why it is so important for us to read at least the aspects of the law that are relevant to what we do. Given the nature of the Internet and computers in general, copyright law is very important to all of us. Despite this, somehow almost no one reads it yet everyone tries to wax intelligent about it.
Many laws are very very cryptic. Luckily, copyright law is not one of them. Go here to obtain a copy of the current U.S. Copyright Law:
http://www.copyright.gov/title17/
Be sure to check back regularly for updates. When reading this document, it is important that you read and understand Chapter 1, Section 101, "Definitions" before reading anything else. If you do not read this and understand it, you *WILL* misunderstand the rest of the document. Once you understand this section, the rest of the document becomes far easier to understand.
Doing this will not prepare you to battle IP lawyers in court, but it will give you a better understanding of copyright in the U.S. and help you avoid copyright issues in the first place. As always, even if you read this law, go hire a real lawyer if you know you are on shaky ground. Attempting to clone someone else' product should immediately make you realize you are on shaky ground, even if you have not read Title 17 of the U.S. Code.
Hint: You don't have to read the entire document. There are sections that do not directly pertain to most modern computing situations. However, it should become very clear very quickly which sections are important to you.
Doing this now will help you to see the infringements you have made in your game. Just one look at the screenshot of your game reveals too many copyright violations to ignore, let alone the text on your web page.