n: 'Test start bounds of step-start easing with no delay',
    effect:     {
                  delay: 0,
                  duration: 1000,
                  fill: 'backwards',
                  easing: 'steps(1, start)'
                },
    conditions: [
                  { currentTime: -1, progress: 0 },
                  { currentTime:  0, progress: 1 }
                ]
  },
  {
    description: 'Test bounds point of step-start easing with reverse direction',
    effect:     {
                  delay: 