I see the problem here. As you are including the files in your class itself, you're correct in that it inherits it, but it retains its scope. Therefore, take header.php as our example, because it is being included in the getHeader() function it will be included correctly, but be classed as part of the class.

Thus, in header.php you can still call the functions in your Layout class, but instead of using the object itself that you created when initiating your class, in your example, $System->Layout, it would simply by $this.

Wrong:

Right:

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