Box shadow
The CSS3 box-shadow property has the following attributes: ( W3Schools )
box-shadow: h-shadow v-shadow blur spread color inset;
In your example, you shift the shadow by 10 pixels vertically and horizontally.
As in other comments, set the first two values ββto 0px to have even a shadow on all sides.
More on Shadows
The main prefix for supporting the latest browsers is box-shadow .
There are 2 others that I recommend using for older Mozilla and Webkit:
-moz-box-shadow-webkit-box-shadow
In addition, using rgba instead of the hex color value, you can set the alpha / opacity of the shadow: box-shadow: 0px 0px 20px 10px rgba(0, 0, 0, 0.3);
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