Add Model(s) to LP and add darkmode

Beside some other improvements, like more info about USP, added first Photo Model (real) images slider and add the mandatory darkmode theme with GPTEngineer (about 15 minutes of work... think in doing it manually...)

Next step is to promote the service directed to Photo Models, together with my GF (is well connected with Models etc). Chicken Egg problem, but as its free for Models, should be more or less easyer part.

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