Answer 1

Hi,

There is no CSS property background-opacity, but you can fake it by inserting a pseudo element with regular opacity the exact size of the element behind it.

body::after {
content: "";
background: url(http://ib1.keep4u.ru/b/070815/ef2714da63d5940bf5.jpg);
opacity: 0.5;
top: 0;
left: 0;
bottom: 0;
right: 0;
position: absolute;
z-index: -1;
}