Cubic-bezier, done for you?

Cubic-bezier, done for you?

Tell us what’s happening:
Hi, on this task relating to cubic-bezier, in the description it say p0 and p4 are done for you as the represent the begging and end points (0,0) and (1,1) but then when you later input the CB it asks you to fill out all 4 P points and p0 is 0.25 while p4 is 0.75? So I don’t understand what it means by done for you?

Thanks as always.

Your code so far


  border-radius: 50%;
  background: linear-gradient(
  position: fixed;
  width: 50px;
  height: 50px;
  margin-top: 50px;
  animation-name: bounce;
  animation-duration: 2s;
  animation-iteration-count: infinite;
#ball1 {
  left: 27%;
  animation-timing-function: cubic-bezier(0.25, 0.25, 0.75, 0.75);
#ball2 {
  left: 56%;
  animation-timing-function: ease-out;

@keyframes bounce {
  0% {
    top: 0px;
  100% {
    top: 249px;


<div class="balls" id="ball1"></div>
<div class="balls" id="ball2"></div>

Your browser information:

User Agent is: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36.

Challenge: Learn How Bezier Curves Work

Link to the challenge:

Sorry I meant P3 not P4.

So the first two numbers are P1 and second two are P2? Think i’ve got it. Or actually i’m not sure about this?