Unclear which window is focused

[st-walker]

It's really not clear just by looking which window is focused. Currently the mode line is slightly darker in colour if the corresponding window is focused, but I think that this isn't enough. It should be clear at a glance which window is focused, and certainly not involve the (relatively) intricate comparison of two very similar shades of grey.

[CSRaghunandan]

It's very easy to modify modeline using set-face-attribute. Considering you use powerline and spaceline themes, here's how I have configured my modeline to look under zenburn. Made it look flat with no boxiness of the default powerline modeline for zenburn :)

You can see my modeline config here