<div class="container"></div>

@layer base, demo;

@layer demo {
  .container {
    background: #fff;
    height: 250px;
    position: relative;
    width: 250px;
  }
  .container::before {
    content: "";
    background-image: url("https://images.unsplash.com/photo-1558244661-d248897f7bc4?crop=entropy&cs=tinysrgb&fm=jpg&ixid=MnwzMjM4NDZ8MHwxfHJhbmRvbXx8fHx8fHx8fDE2NjYxMTE5MjA&ixlib=rb-1.2.1&q=80");
    background-size: 250px;
    border-radius: 30px;
    height: 100%;
    left: -30px;
    top: -30px;
    padding: 30px;
    position: absolute;
    width: 100%;
    z-index: -1;
  }
}

@layer base {
  body {
    display: grid;
    place-items: center;
    height: 100vh;
  }
}