The justify-content:center property aligns bend elements along the bend direction - use align-items:center - see the demo below:
.container { display: flex; flex-direction: column; width: 600px; background-color: blue; justify-content: center; align-items:center; } .item { max-width: 500px; width: 250px; height: 100px; background-color: yellow; border: 2px solid red; }
<div class="container"> <div class="item"></div> <section class="item"></section> <section class="item"></section> <footer class="item"></footer> </div>
Contact: Flexbox W3C Specification
The following is an image that applies when flex-direction is a string:

a. Main axis alignment: justify-content
b. Alignment: Alignment
When the flex-direction row is a row, the main axis is horizontal, but when it is a column, it is the other way around.
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