.wrap{

position: relative;

width: 1200px;

height: 400px;

background: url(img/timg.jpg) no-repeat center center;

background-size: cover;

}

.wrap::before {

content: "";

position: absolute;

left: 0;

right: 0;

bottom: 0;

top: 0;

background-color: rgba(0, 0, 0, .5);

z-index: 2;

}