make div cover background code example

Example 1: is there an img cover

body {
  margin: 0;
}
img {
  display: block;
  width: 100vw;
  height: 100vh;
  object-fit: cover;
}

Example 2: fill and no repeat background image css

/* with CSS 3 */
#yourdiv {  
    background: url('bgimage.jpg') no-repeat;
    background-size: 100%;
}