I completed the step, but I dont understand what I did. Registration Form - step 45

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what did i do here
what did i do here1905×833 165 KB

Title and image, I completed it on the first try which is nice, but I’ve been a bit overwhelmed with information and really don’t understand what exactly my actions did. Can someone explain it to me please?

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Hi! Here is a guide about centering:

And about relative length units:

Hope you will the info you need here