:root {
  --device-width: 770px;
  --device-height: 1336px;
  --ui-width: 640px;
  font-size: 15px;
}

body {
  background-color: #000;
  margin: 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  font-family: Helvetica;
  padding: 4rem 0;
}

h2 {
  color: #6e6e73;
  text-align: center;
  font-size: 4.5rem;
  font-weight: 600;
  margin: 6rem 0;
}

h2 p {
  margin: 0;
  color: #fff;
}

#iphone {
  position: relative;
  width: var(--device-width);
  height: var(--device-height);
}

#hardware {
  width: 100%;
  height: 100%;
  background-image: url(https://assets.codepen.io/2002878/iphone12-5g_on_phone.jpg);
  background-size: var(--device-width) var(--device-height);
  
  mask-image: url(https://assets.codepen.io/2002878/iphone12-5g_on_phone_mask.png);
  -webkit-mask-image: url(https://assets.codepen.io/2002878/iphone12-5g_on_phone_mask.png);
  
  mask-size: var(--device-width) var(--device-height);
  -webkit-mask-size: var(--device-width) var(--device-height);
}

#ui {
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
}

#ui .top-ui {
  display: block;
  width: var(--ui-width);
  height: auto;
  margin: 70px auto 0;
  padding-bottom: 30px;
  border-bottom: 1px solid #222;
}

#ui ul {
  list-style: none;
  margin: 0;
  padding: 0;
  --progress: 0;
}

#ui ul li img {
  display: block;
  width: var(--ui-width);
  height: auto;
  margin: 10px auto;
  padding-bottom: 10px;
  border-bottom: 1px solid #222;
  transform: scale(calc(1.8 - (0.8 * var(--progress)))) translateY(calc(-60px * (1 - var(--progress))));
  opacity: var(--progress);
}