As the exercise explains, the flex-grow property specifies if items should grow to fill a container. I don’t see flex-items stretching themselves vertically to fill the flex container. I noticed that flex-items fill the flex container horizontally by their margins, but it does not happen vertically (see image). So when I declare flex-items with the 'flex-grow property, they will never fill 100% of the parent container? Does the flex-grow property stretch flex items horizontally to fill the container 100% in width but does not happen the same vertically? I thought the flex-grow property would make the flex items fill 100% vertically and horizontally the flex container.
They fill horizontally by using margins but, not vertically as I said.