The box-shadow can hold 4 length parameters + a color.

1. X-offset (horizontal)
2. Y-offset (vertical)
3. Blur
4. Spread (width of the shadow)

/* -- START add box shadow -- */
.hws-boxshadow {
box-shadow: 0px 0px 20px 0px #000000;
}
/* -- END add box shadow -- */
Code language: CSS (css)

More info:

• https://www.w3schools.com/css/css3_shadows_box.asp
• https://developer.mozilla.org/en-US/docs/Web/CSS/box-shadow