Coca is a small app that allows you to prevents your Mac from going to sleep. A left-click shows it's menu. Right-click the Coca icon in the menu bar to activate it and again to deactivate.
Coca supports the dark menu bar introduced in OS X Yosemite.
Specify your desired behavior for Coca.
For example left-clicking the menu bar icon to activate and more.
For only 0.99$ Coca Extras unlocks additional options
More activation settings, menu bar icons and custom icon support.