   var radians: Float {
     return self * (Float(180) / Float(M_PI))
   }
-  
+
   var degrees: Float {
     return self  * Float(M_PI) / 180.0
   }
 }
 
 internal extension UIView {
-  
+
   var angleZ: Float {
     return atan2(Float(self.transform.b), Float(self.transform.a)).radians
   }

                      self.transform = CGAffineTransform(scaleX: 0.001, y: 0.001)
      }, completion: nil)
  }
  
  fileprivate func showCenterButton(duration: Float, delay: Double) {
    UIView.animate( withDuration: TimeInterval(duration), delay: TimeInterval(delay), usingSpringWithDamping: 0.78,
                    initialSpringVelocity: 0, options: UIViewAnimationOptions.curveLinear,

                         constant:0)
    }
    superview?.addConstraints(centerConstraints)

    return platform
  }

  // MARK: configure
  fileprivate func addActions() {
    self.addTarget(self, action: #selector(CircleMenu.onTap), for: UIControlEvents.touchUpInside)
  }

  // MARK: actions

  func onTap() {
    if buttonsIsShown() == false {
      let platform = createPlatform()
