html, body {
    height: 100%;
    background-color: black;
}
.container {
  position: relative;
  width: 100%;
  height: 100%;
  outline: dashed 1px black;
  display: block;
}

 .jpg {
    width: 90%;
  height: 90%;
     margin: 0 auto;
}
img {
    width: 100%;
  height: auto;
}