The challenge wants you to use linear-gradient to make a beautiful background that starts with a color and ends with another one (a combination of colors: the challenge asks for 2 only).
This one => #CCFFFF is the first color.
This => #FFCCCC is the second one.
And this => 35deg is the degree: from where the first color starts to where the second one ends.
Linear gradient takes the degree; first color, and then the second color as in the following:
linear-gradient(35deg, #CCFFFF, #FFCCCC);
To what this linear-gradient should be applied?
It’s up to you to find where it should be used in this challenge.