Check out example codes for "change button shaddow css". It will help you in understanding the concepts better.

Code Example 1

button{
  2.5px 2.5px 2px #888;
}

Code Example 2

/* CSS box shadow look like paper lift up*/
/* provide shadow to all four corners */
/* source - W3Schools.com */
 box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19);

Code Example 3

div.card
{

  width: 250px;
  box-shadow: 0 4px 8px 0 rgba(0, 0, 
0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19);
  text-align: 
center;

}

Code Example 4

#example1 {
  box-shadow: 10px 10px 8px #888888;
}

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