Let me be honest with you, nothing is ever going to beat black (for me), nevertheless I am very into cobalt/electric blue at the moment. It gives such a crisp and fresh vibe, and it makes wearing white during fall very okay.
I am wearing a cobalt blue coat by H&M Trend (best option here, or here and here), a navy jumper (similar here) and black ankle boots from Zara, a white MIH Jeans Marrakesh flare jeans, my new Celine sunglasses, and of course… my famous PS11!