add box shadow on box code example

Example 1: css box shadow

/* offset-x | offset-y | blur-radius | spread-radius | color */
box-shadow: 2px 2px 2px 1px rgba(0, 0, 0, 0.2);

Example 2: box-shadow

blockquote {
  padding: 20px;
  box-shadow: 
       inset 0 -3em 3em rgba(0,0,0,0.1), 
             0 0  0 2px rgb(255,255,255),
             0.3em 0.3em 1em rgba(0,0,0,0.3);
}