Last question on Applied Visual Design

To see the effect of this Bezier curve in action, change the animation-timing-function of the element with id of red to a cubic-bezier function with x1, y1, x2, y2 values set respectively to 0, 0, 0.58, 1. This will make both elements progress through the animation similarly.

    background: red;
    left: 27%;
    animation-timing-function: cubic-bezier:( 0, 0, 0.58, 1);
  }

removed extra : woohoo

Remove the colon (:) in front of the function name.

animation-timing-function: cubic-bezier( 0, 0, 0.58, 1);