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Edward Ulick
2,756 PointsBackground-position values
In the video you leave the initial value of 50% in the expression, like this:
background-position: calc(100% - 40px) calc(100% + 30px), 50%;
What is the purpose of leaving the "50%" in there, it doesn't seem to do anything? I checked MDN, and it says that background position only takes 2 values, and x and y position (or certain keywords). Thanks!
4 Answers
Patrick McKinney
13,151 PointsHe is using two images as the background for .main-header class. The calc() code in background-position is for the rock image, while the 50% is the background-position for the larger image.
I believe using 50% sets both the x and y to 50%.
Rachel Campbell
9,103 PointsThis is how I'm understanding it. The , 50% is for the second background image (header-bg.png). If you change 50% to 100%, for example, you can see the header-bg.png image change position. Change it to 1000% and it disappears off the page completely.
You have: Specifying paths to background-image 1 (the rock) COMMA background-image 2 (the beach). Position value for background-image 1 (the rock) COMMA position value for background image 2 (the beach).
The COMMA , separates the two declarations. And that separation is preserved in the next CSS declaration (for position).
Godfrey M
Courses Plus Student 2,696 Pointsi also have the same question as Edward Ulick, why cant a teacher come in here and elaborate it more. we are all assuming , what is the correct answer ?? after students ,moderator should interact with us, this forum is self taught i think.
Cindy Lea
Courses Plus Student 6,497 PointsIt is 2 values. The first argument uses the calc function that subtracts 2 values for you & puts the result as argument 1. Its just easier to do than using your calculator everytime.
Edward Ulick
2,756 PointsThanks for your reply! I was actually asking why he leaves the "50%" in the code? What I meant was why does he write it like this:
background-position: calc(100% - 40px) calc(100% + 30px), 50%;
as opposed to this:
background-position: calc(100% - 40px) calc(100% + 30px);
Those two rules seem to do exactly the same thing, so why does he leave the 50% there?