discourse-rewind/assets/stylesheets/common/reading-time.scss

.reading-time__book {
  display: flex;
  align-items: center;
  justify-content: center;
  perspective: 1000px;
}

.book {
  width: 150px;
  height: 200px;
  position: relative;
  transform-style: preserve-3d;
  transform: rotateY(-20deg);
}

.reading-time code {
  background-color: rgba(var(--primary-rgb), 0.15);
}

.book > :first-child {
  position: absolute;
  top: 0;
  left: 0;
  width: 150px;
  height: 200px;
  transform: translateZ(17.5px);
  background-color: #01060f;
  border-radius: 0 5px 5px 0;
  box-shadow: 5px 5px 20px rgba(var(--primary-rgb), 0.05);
}

.book::before {
  position: absolute;
  content: " ";
  background-color: blue;
  left: 0;
  top: 4px;
  width: 33px;
  height: 192px;
  transform: translateX(128.5px) rotateY(90deg);
  background: linear-gradient(
    90deg,
    #fff 0%,
    #f9f9f9 5%,
    #fff 10%,
    #f9f9f9 15%,
    #fff 20%,
    #f9f9f9 25%,
    #fff 30%,
    #f9f9f9 35%,
    #fff 40%,
    #f9f9f9 45%,
    #fff 50%,
    #f9f9f9 55%,
    #fff 60%,
    #f9f9f9 65%,
    #fff 70%,
    #f9f9f9 75%,
    #fff 80%,
    #f9f9f9 85%,
    #fff 90%,
    #f9f9f9 95%,
    #fff 100%
  );
}

.book::after {
  position: absolute;
  top: 0;
  left: 0;
  content: " ";
  width: 150px;
  height: 200px;
  transform: translateZ(-17.5px);
  background-color: var(--book-color);
  border-radius: 0 5px 5px 0;
}

.reading-time__text {
  font-weight: normal;
  width: 50%;
}

.reading-time .rewind-card {
  gap: 1em;
  padding: 1.5em;
  flex-direction: row;
  justify-content: space-around;
  align-items: center;
  background-color: var(--secondary);
  --book-color: rgba(var(--primary-rgb), 0.4);
  @include rewind-border;
}