Spain was ruled by an Islamic State. For how many years? How widespread was interbreading?

I don't know if you've ever been to Spain, but if you have, you will notice a very mive islamic influence in the south today. In the region of Andalucia, all destination signs on the freeway are in both arabic and castillian. In Granada, the Alhambra still stands. This indicates that, at the very least, castillians interbreeded with moors when they took Granada. Otherwise, the people, culture, and architecture would not still be standing there today. Modern Spaniards, like most Europeans, are not purebred Spanish. It's so easy to move around Europe. I would guess that 95% or more of the Spaniards of southern Spain have moorish blood. Islam, as far as I know, does not condone slavery. This would allow for interbreeding without backlash from the islamic community. It makes perfect sense for them to have mixed both blood and culture.