Check out example codes for "box bottom shadow css". It will help you in understanding the concepts better.

Code Example 1

div {
     box-shadow: inset 0 0 10px #000000;
}

Code Example 2

.box-bottom-shadow {
	-webkit-box-shadow: 0 8px 6px -6px black;
	   -moz-box-shadow: 0 8px 6px -6px black;
	        box-shadow: 0 8px 6px -6px black;
}

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