It's a gray app on your home screen that contains an image of gears (⚙️).
 It's near the top of the menu next to a gray icon that contains an image of white sliding buttons.
 It will turn green.
 It will turn green, and now you can access the Control Center from any screen on your device.
Open your device's Settings.
Tap Control Center.
Slide the button next to "Access on Lock Screen" to the "On" position.
Slide the button next to "Access Within Apps" to the "On" position.
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