Well, inside the body, I put two boxs, col-md-6, with 1px border, but one was next to the other, and it was not to stay, then I put a margin-left of 28px in the two boxs my left side of the screen, ie second and fourth. There it separated, the ones on the left corner went to Container limit, and the medium was no longer together, as in the image:
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But when it decreases to see how to stay responsive, the second and fourth were not responsive, due to the margin-left, follow the print of the pordas, which should be on the same margin, 0,
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