gui question

i was wondering how you if possable to change the colour of the gui in blender ive seen some pictures of it being a black like colour instead of the defualt grey i was wondering how you can do this if possable.

thanks

You can do that by dragging settings down from the up part of the screen (below File, Add, …) and then going to Themes. You can change theme there or even create your own if you like.