Wort boil

I did my second all grain brew this weekend Lloyd's Krispy Kolsch beersmith recipe. - my first BIAB  .
Everything went well, gathered 7.5 gallons of wort , boiled for 60 minutes, about 220F, lid off the brew pot.  Ended up with only 4 gallons and the color was more like a black lager than a kolsch.  Any idea what  I did wrong?  Can you boil at too high a temperature?  60 minutes was the recipe boil time.

What was your grain bill?  Did the bag scorch on the bottom of the boil kettle?  I don't BIAB, but unless you acceidentallly had some dark grains (it wouldn't take much) or something burnt, I can't see how your color could be off that much.