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Olivia Van Buskirk
353 PointsWhen editing the margin using CSS, what does "auto" do, and what does "0" do?
I'm jnot sure exactly what these do on the page!
a {
text-decoration: none;
}
#wrapper {
max-width: 940px;
margin: 0 auto;
}
1 Answer
colingallagher
9,743 PointsThe value of said property is adjusted automatically according to the content or the context of the element.
For example, a block-level element with height: auto will grow taller as it contains more text. For another example, a block element with margin: 0 auto will have the left and right margins increased until it becomes centered along the y-axis of the viewport.
It really depends on the property you give the value to, different properties behave differently depending on the content and context.
Jonathan Fernandes
Courses Plus Student 22,784 PointsJonathan Fernandes
Courses Plus Student 22,784 PointsHi Olivia,
Basically, you are telling it to center the wrapper in it's parent container.
Normally when setting a margin, it goes clockwise. First you set the top, then the right, then the bottom, then the left. So if you changed it to "margin: 10px 15px 20px 25px;" then you are telling it to move the element 10 pixels from the top, 15 pixels from the right, 20 pixels from the bottom, and 25 pixels from the left.
Now when you set a max width, adding auto will automatically center that element so that the left and right have an equal amount of pixels separating the element from the parent container's borders.
Does that answer your question?