@font-face {
  font-family: PixelText;
  src: url(https://assets.codepen.io/36869/Grand9KPixel.ttf);
}

:root {
  font-family: 'PixelText', serif;
  font-optical-sizing: auto;
  line-height: 1.5;
  font-weight: 400;

  color-scheme: light dark;
  color: rgba(255, 255, 255, 0.87);
  background-color: #242424;

  font-synthesis: none;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow: hidden;

  /* sprite image */
  --sprite-image: url(https://assets.codepen.io/36869/book.webp);

  /* sprite animation settings */
  /* animation duration */
  --sprite-as: .8s;
  /* animation direction */
  --sprite-ad: normal;
  /* animation fill mode */
  --sprite-af: none;
  /* animation play state */
  --sprite-ap: running;
  /* animation iteration count */
  --sprite-ai: infinite;
  /* animation timing function */
  --sprite-at: linear;
  /* animation frame rate */
  --sprite-fr: 12;
}

@layer base {
  *{
    box-sizing: border-box;
  }
  body {
    margin: 0;
    height: 100vh;
    width: 100vw;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    box-sizing: border-box;
    padding: 1rem;
  }

  .sprite-wrapper {
    position: relative;
    width: 100%;
    margin: 0 auto;
  }
}

@layer main {
  /* Frame start position */
  @property --sprite-fs {
    syntax: "<integer>";
    initial-value: 0;
    inherits: true
  }
  @property --_progress {
    syntax: "<percentage>";
    inherits: false;
    initial-value: 0%;
  }

  .container {
    display: flex;
    flex-direction: column;
    gap: 3rem;

    /* sprite columns */
    --sprite-c: 5;
    /* sprite image height */
    --sprite-h: 3000;
    /* sprite image width */
    --sprite-w: 9600;
    /* sprite frames */
    --sprite-f: 7;
    /* animation duration based on frame rate */
    --sprite-as: calc(var(--sprite-f) / var(--sprite-fr) * 1s);

    /* frame rows */
    --sprite-r: round(up, calc(var(--sprite-f) / var(--sprite-c)), 1);
    /* frame height */
    --sprite-sh: calc(var(--sprite-h) / var(--sprite-r));
    /* frame target height, width */
    --sprite-th: calc(var(--sprite-sh) / 2);

    /* aspect ratio */
    --sprite-ar: calc(var(--sprite-th) / var(--sprite-sh));
    --sprite-uh: calc(var(--sprite-h) * var(--sprite-ar));
    --sprite-uw: calc(var(--sprite-w) * var(--sprite-ar));

    /* frame width */
    --sprite-tw: calc(var(--sprite-uw) / var(--sprite-c));

    > h1 {
      color: #d2d4e1;
      margin: 0;
      width: fit-content;
      font-weight: 500;
      font-size: 1.75rem;
      text-align: center;
    }

    .book {
      position: relative;
      display: grid;
      grid-template-areas:
            "scroll scroll scroll"
            "left markers right";
      gap: 1rem;

      .sprite {
        position: absolute;
        display: flex;
        align-items: center;
        justify-content: center;
        height: calc(1px * var(--sprite-th));
        width: calc(1px * var(--sprite-tw));
        margin: calc(-1px * calc((var(--sprite-th) - (var(--sprite-th) * 0.6107)) / 2)) calc(-1px * calc((var(--sprite-tw) - (var(--sprite-tw) * 0.7042)) / 2));
        background-image: var(--sprite-image);
        transform-origin: center center;
        background-repeat: no-repeat;
        background-size: calc(1px * var(--sprite-uw)) calc(1px * var(--sprite-uh));
        z-index: -1;

        /* Frame end position */
        --sprite-fe: calc(var(--sprite-f) * (var(--slides) - 1));
        --sprite-fs-n: mod(var(--sprite-fs), var(--sprite-f));
        /* calculate the row and column position */
        --row: calc(round(down, calc(calc(var(--sprite-tw) * var(--sprite-fs-n)) / var(--sprite-uw)), 1) * var(--sprite-th));
        --col: mod(calc(var(--sprite-tw) * var(--sprite-fs-n)), var(--sprite-uw));

        background-position: calc(-1px * var(--col)) calc(-1px * var(--row));
        animation: frame var(--sprite-as) var(--sprite-at) 0s var(--sprite-ad) var(--sprite-af) var(--sprite-ap);
        animation-timeline: --carousel-timeline;
      }

      .carousel {
        counter-increment: curpage;
        grid-area: scroll;
        overflow-x: auto;
        scroll-snap-type: x mandatory;
        overscroll-behavior-x: contain;

        display: grid;
        margin: 0 auto;
        width: calc(1px * (var(--sprite-tw) * 0.7042));
        height: calc(1px * (var(--sprite-th) * 0.6107));
        grid: 1fr / auto-flow 100%;
        scroll-timeline: --carousel-timeline x;
        scroll-behavior: smooth;
        scrollbar-width: none;
        scroll-marker-group: after;

        &::scroll-button(*) {
          inline-size: 64px;
          aspect-ratio: 1;
          border-radius: 0;
          border: 0;
          background-color: transparent;
          cursor: pointer;
        }

        &::scroll-button(*):disabled{
          filter: invert(1);
          opacity: 0.5;
        }
        &::scroll-button(*):not(:disabled):is(:hover, :active) {
          filter: drop-shadow(2px 4px 6px black);
        }

        &::scroll-button(*):not(:disabled):active {
          scale: 90%;
        }

        &::scroll-button(left) {
          content: url("data:image/svg+xml;base64,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") / "Scroll Left";
          grid-area: left;
        }

        &::scroll-button(right) {
          content: url("data:image/svg+xml;base64,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") / "Scroll Right";
          grid-area: right;
          justify-self: flex-end;
        }

        &::scroll-marker-group {
          content: "";
          width: 100%;
          height: 8px;
          padding: 2px 0;
          display: grid;
          position: absolute;
          grid-area: markers;

          grid-auto-flow: column;
          place-self: center;
          overflow: hidden;
          border: 1px solid #000;

          background: linear-gradient(90deg, #f1e2b2 0%) no-repeat left center;
          --_progress: calc(calc(100 / var(--slides)) * 1%);
          background-size: var(--_progress, 20%) 100%;

          animation: progress linear both;
          animation-timeline: --carousel-timeline;
        }

        & > .carousel-item {
          scroll-snap-stop: always;
          scroll-snap-align: start;
          animation: count-before linear forwards;
          animation-range: exit;
          counter-increment: page;
          animation-timeline: view(x);

          position: relative;
          box-sizing: border-box;
          color: #333;

          &::scroll-marker {
            content: '';
            position: relative;
            left: -1px;
            width: 100%;
            height: 100%;
            display: block;
            box-sizing: border-box;
            box-shadow: 2px 0 0 #000;
          }

          &:last-of-type{
            &::scroll-marker {
              box-shadow: none;
            }
          }

          .page-container {
            display: flex;
            gap: 3rem;
            height: 100%;

            animation: stay-centered linear both;
            animation-timeline: view(x);
            timeline-scope: --parallax-item;
          }

          .left-page, .right-page {
            flex: 1;
            font-size: small;
            overflow: hidden;
            display: grid;
            grid-template-rows: 1fr auto;

            &:after {
              bottom: 15px;
              color: hsl(45.71deg 69.23% 30%);
            }

            > div {
              text-align: justify;
              hyphens: auto;
              line-height: normal;
              display: block;
              word-wrap: break-word;
            }
          }

          .left-page {
            padding: 20px 0 20px 20px;
            &:after {
              content: counter(curpage);
            }
          }

          .right-page {
            padding: 20px 20px 20px 0;
            counter-increment: curpage;
            &:after {
              content: counter(curpage);
              place-self: self-end;
            }
          }
        }
      }
    }
  }
}

@media (width < 748px) {
  .container {
    --sprite-th: calc(var(--sprite-sh) / 2.5);

    > h1 {
      font-size: 1.25rem;
    }

    .page {
      > div {
        font-size: .6rem;
      }
    }
  }
}

@media (width < 560px) {
  .container {
    --sprite-th: calc(var(--sprite-sh) / 4);

    > h1 {
      font-size: 1rem;
    }

    .page {
      > div {
        font-size: .35rem;
      }

      &:after {
        font-size: .5rem;
      }
    }
  }
}

@keyframes stay-centered {
  entry 0% {
    opacity: 0;
    translate: -100%;
  }
  entry 75%  {
    opacity: 0;
    translate: -25%;
  }
  entry 100% {
    opacity: 1;
    translate: 0%;
  }
  exit 0% {
    opacity: 1;
    translate: 0%;
  }
  exit 50% {
    opacity: 0;
    translate: 50%;
  }
  exit 100% {
    opacity: 0;
    translate: 100%;
  }
}

@keyframes count-before {
  1%,
  100% {
    counter-increment: page curpage;
  }
}

@keyframes progress {
  100% {
    --_progress: 100%;
  }
}

@keyframes frame {
  to {
    --sprite-fs: var(--sprite-fe);
  }
}

@media (prefers-reduced-motion) {
  * {
    animation: none;
  }
}