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CSS

Matthias Nörr
Matthias Nörr
8,614 Points
Posted by Matthias Nörr
Matthias Nörr
8,614 Points

CSS that always centers an image vertically: Please explain

This Css always centers an image vertically:

.overlay:before {                   
    content: '';
    display: inline-block;
    height: 100%;
    vertical-align: middle;
}

.overlay img {
    max-height: 100%;               
    max-width: 100%;                
    display: inline-block;
    vertical-align: middle;


}

The trick is creating a ghost-container around the image, that needs to be centered. This works really well and is also responsive.

Can someone explain this technique to me?

1 Answer

Matthias Nörr
Matthias Nörr
8,614 Points
Matthias Nörr
Matthias Nörr
8,614 Points

Margin: 0 auto did not work. And I would like to know why. Also consider that the image is then only centered horizontally and not vertically.

I should probably explain that the image is shown in an overlay that is pasted into the HTML by Jquery. I also use Bootstrap 3.