Code Playground

@charset "UTF-8";
@import url(https://fonts.googleapis.com/css?family=Nunito+Sans:300,400,600,700,800);
*,
:after,
:before {
  box-sizing: border-box;
  padding: 0;
  margin: 0;
}
@import url("https://fonts.googleapis.com/css2?family=Press+Start+2P&display=swap");

@font-face {
  font-family: "Doom";
  src: url("https://assets.codepen.io/383755/Upheaval.woff2") format("woff2");
}

body,
html {
  image-rendering: pixelated;
  cursor: crosshair;
  position: fixed;
  overflow: hidden;
  * {
    cursor: crosshair;
  }
  &:has(.inner span:nth-of-type(6) input:checked) {
    &:before {
      opacity: 1;
    }
  }
  &:has(#logo input:checked) {
    @supports (animation-timeline: scroll()) {
      position: relative;
      overflow: auto;
    }
    #weapon {
      bottom: 50px;
    }
    #hud {
      transform: translateY(0);
    }
    &:active #weapon {
      animation: shoot 0.125s steps(3, end) 1;
      @keyframes shoot {
        to {
          background-position: -255px 20px;
        }
      }
    }
  }
}

body {
  background: #000;
}

body:before {
  content: "victory";
  color: #222;
  background: rgba(255, 0, 0, 0.75);
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  width: 100vw;
  position: fixed;
  z-index: 9999;
  top: 0;
  left: 0;
  font-family: "Doom";
  font-size: 14vmin;
  backdrop-filter: blur(4px);
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.3s ease-in-out 0.5s;
}

// Let's hide the scrollbars

::-webkit-scrollbar {
  width: 6px;
  height: 0px;
}

::-webkit-scrollbar-track {
  background: #000;
}

::-webkit-scrollbar-thumb {
  background: linear-gradient(to bottom, #e9544b, #f9ef51 75%);
}

// Here's our character movement

@keyframes rotate {
  0% {
    transform: translateY(0px);
  }
  20% {
    transform: translateY(150px) rotate(0deg);
  }
  30% {
    transform: translateY(200px) rotate(90deg);
    transform-origin: 50% calc(50% + 100px);
  }
  40% {
    transform: translateY(300px) rotate(90deg);
    transform-origin: 50% calc(50% - 0px);
  }
  50% {
    transform: translateX(100px) translateY(300px) rotate(0deg);
    transform-origin: 50% calc(50% - 0px);
  }
  60% {
    transform: translateX(100px) translateY(400px) rotate(0deg);
    transform-origin: 50% calc(50% - 150px);
  }
  65% {
    transform: translateY(450px) rotate(-90deg);
    transform-origin: 50% calc(50% - 200px);
  }
  75% {
    transform: translateY(550px) rotate(-90deg);
    transform-origin: 50% calc(50% - 200px);
  }
  80% {
    transform: translateY(600px) rotate(-90deg);
    transform-origin: 50% calc(50% - 200px);
  }
  85% {
    transform: translateX(100px) translateY(650px) rotate(-180deg);
    transform-origin: 50% calc(50% - 200px);
  }
  90% {
    transform: translateX(100px) translateY(800px) rotate(-180deg);
    transform-origin: 50% calc(50% - 200px);
  }
  100% {
    transform: translateX(200px) translateY(800px) rotate(-180deg);
    transform-origin: 50% calc(50% - 200px);
  }
}

#level {
  transform: translateY(0px) translateZ(300px) rotateX(85deg);
}
.inner {
  animation: rotate linear;
  animation-timeline: scroll();
  animation-range: entry 0 cover 100%;
  transform-origin: 50% calc(50% + 100px);
}

body {
  display: grid;
  place-items: center;
  height: clamp(1200px, 2000vh, 2000vh);
  width: 100vw;
  pointer-events: none;
  * {
    pointer-events: none;
  }
  &:has(#logo input:checked) {
    #wrapper #level .inner {
      span:first-of-type {
        animation-play-state: running;
      }
    }
  }
  input {
    @supports (animation-timeline: scroll()) {
      pointer-events: all;
    }

&:checked {
      pointer-events: none;
    }
  }
}

#wrapper {
  width: 600px;
  height: 600px;
  box-shadow: 0 0 0 1px;
  position: fixed;
  top: calc(50vh - 300px);
  left: calc(50vw - 300px);
  perspective: 600px;
  z-index: -1;
}

#level {
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;

transform-style: preserve-3d;
  * {
    transform-style: preserve-3d;
    &:before,
    &:after {
      transform-style: preserve-3d;
    }
  }
  .inner {
    background: url("https://assets.codepen.io/383755/C99.png");
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    display: grid;
    grid-template-columns: repeat(9, 1fr);
    grid-template-rows: repeat(9, 1fr);
    grid-column-gap: 0px;
    grid-row-gap: 0px;
    &:before {
      content: "";
      position: absolute;
      width: 100%;
      height: 100%;
      background: url("https://assets.codepen.io/383755/C64.png");
      top: 0;
      left: 0;
      transform: translateZ(calc(600px / 9));
    }
    svg {
      position: absolute;
      width: 100%;
      height: 100%;
      path {
        fill: none;
        stroke: red;
        stroke-width: 10px;
      }
    }
  }
  .inner > span {
    image-rendering: pixelated;
    grid-area: 7 / 5 / 8 / 6;
    transform-origin: bottom;
    --y: 0deg;
    --x: -90deg;
    position: relative;
    transform: rotateX(var(--x)) rotateY(var(--y)) scale(0.75) translateZ(-50px);
    animation: approach 2s steps(18, end) 1 forwards var(--delay, 0s);
    animation-play-state: paused;
    @keyframes approach {
      to {
        transform: rotateX(var(--x)) rotateY(var(--y)) scale(0.75)
          translateZ(var(--z, 50px));
      }
    }
    &:nth-of-type(2),
    &:nth-of-type(3) {
      grid-area: 5 / 3 / 6 / 4;
      --y: 90deg;
      --delay: 2s;
    }
    &:nth-of-type(3) {
      grid-area: 6 / 3 / 7 / 4;
      --z: 0px;
      --delay: 0s;
      &:before {
        background: url(https://assets.codepen.io/383755/demon1.gif) 50% 50% /
          contain no-repeat;
      }
    }
    &:nth-of-type(4) {
      grid-area: 2 / 8 / 3 / 9;
      --y: -90deg;
      --delay: 2s;
      &:before {
        background: url(https://assets.codepen.io/383755/caco-cacodemon.gif) 50%
          50% / contain no-repeat;
      }
      &:before,
      &:after {
        left: -25%;
      }
    }
    &:nth-of-type(5) {
      grid-area: 5 / 7 / 6 / 8;
      --y: -180deg;
      --delay: 2s;
      &:before {
        background: url(https://assets.codepen.io/383755/demon1.gif) 50% 100% /
          contain no-repeat;
      }
    }
    &:nth-of-type(6) {
      grid-area: 8 / 8 / 9 / 9;
      --y: -180deg;
      --delay: 0s;
      &:before {
        background: url(https://assets.codepen.io/383755/demon4.gif) 50% 100% /
          contain no-repeat;
        width: 150%;
        left: -25%;
      }
    }
    &:has(input:checked) {
      &:after {
        opacity: 1;
        animation-play-state: running;
      }
      &:before {
        opacity: 0;
      }
      & + span {
        animation-play-state: running;
      }
    }
    &:before,
    &:after {
      content: "";
      position: absolute;
      width: calc(100% - 18px);
      height: 100%;
      bottom: 0;
      left: 0;
      --offset: 3px;
      pointer-events: none;
      background: url(https://assets.codepen.io/383755/demon3.gif) 50% 25% /
        contain no-repeat;
    }
    &:after {
      --offset: 0px;
      animation: move 0.5s steps(6, end) 1 forwards;
      background: url("https://assets.codepen.io/383755/doom-explosion.png") 2px
        50% / auto 50px no-repeat;
      animation-play-state: paused;
      @keyframes move {
        to {
          background-position: calc(100% + var(--offset)) 50%;
        }
      }
      opacity: 0;
    }
    input {
      position: absolute;
      width: 100%;
      height: 100%;
      top: 0;
      left: 0;
      opacity: 0;
      z-index: 999;
    }
  }
  .inner > div {
    &:before,
    &:after {
      content: "";
      position: absolute;
    }
    &:nth-of-type(1) {
      grid-area: 9 / 4 / 10 / 6;
      background: url("https://assets.codepen.io/383755/C4.png");
      transform-origin: bottom;
      transform: rotateX(-90deg) rotateY(-90deg);
      &:before {
        content: "";
        position: absolute;
        width: 300%;
        height: 100%;
        top: 0;
        right: 50%;
        transform: translateZ(calc(600px / -9));
        background: inherit;
      }
    }
    &:nth-of-type(2) {
      background: url("https://assets.codepen.io/383755/C4.png");
      grid-area: 8 / 2 / 9 / 5;
      transform-origin: bottom;
      transform: rotateX(-90deg);
      &:before,
      &:after {
        height: 100%;
        width: 200%;
        right: 100%;
        top: 0;
        background: url("https://assets.codepen.io/383755/C4.png");
        transform-origin: right;
        transform: rotateY(-90deg);
      }
      &:after {
        background: url("https://assets.codepen.io/383755/C19.png");
        width: 66%;
        right: 0%;
      }
    }
    &:nth-of-type(3),
    &:nth-of-type(5) {
      grid-area: 2 / 2 / 3 / 3;
      transform-origin: bottom;
      transform: rotateX(-90deg);
      background: url("https://assets.codepen.io/383755/C19.png");
      &:before {
        width: 200%;
        height: 100%;
        left: -100%;
        transform-origin: right;
        top: 0;
        transform: rotateY(-90deg);
        background: url("https://assets.codepen.io/383755/C4.png");
      }
    }
    &:nth-of-type(4) {
      grid-area: 1 / 1 / 2 / 10;
      transform-origin: bottom;
      transform: rotateX(-90deg);
      background: url("https://assets.codepen.io/383755/C4.png");
      &:before,
      &:after {
        width: 100%;
        height: 100%;
        top: 0;
        left: 0;
        background: url("https://assets.codepen.io/383755/C4.png");
        transform: rotateY(90deg);
        transform-origin: right;
      }
      &:after {
        left: auto;
        right: 0;
        width: 44%;
        transform: translateZ(500px);
        background: url("https://assets.codepen.io/383755/C4.png");
      }
    }
    &:nth-of-type(5) {
      grid-area: 4 / 5 / 5 / 6;
      &:before,
      &:after {
        width: 100%;
        height: 100%;
        background: inherit;
        top: 0;
        left: 0;
        transform-origin: left;
        transform: rotateY(90deg);
      }
      &:after {
        width: 200%;
        transform: translateZ(200px);
        left: 101%;
      }
    }
  }
}

#logo {
  position: fixed;
  background: url("https://assets.codepen.io/383755/580b57fcd9996e24bc43c34d.png")
      50% 50% / auto 40vh no-repeat,
    rgba(0, 0, 0, 0.75);
  z-index: 10;
  width: 100vw;
  height: 100vh;
  top: 0;
  left: 0;
  animation: load 0.5s ease-in-out 1 forwards paused;
  pointer-events: none;
  transition: 0.3s ease-in-out;
  &:has(input:checked) {
    animation-play-state: running;
    background-position: 50% calc(50% - 100vh);
    &:before,
    &:after {
      transform: translate(-50%, 100vh);
    }
  }
  input {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    opacity: 0;
  }
  &:before,
  &:after {
    content: "scroll";
    font-family: "Doom";
    color: #f9ef51;
    background-image: linear-gradient(to bottom, #e9544b 0%, #f9ef51 50%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    font-size: 8vh;
    position: absolute;
    left: 50%;
    top: calc(50% + 10vh);
    transform: translate(-50%, 0);
    transition: 0.3s ease-in-out 0.05s;
  }
  &:before {
    -webkit-text-stroke: 2px #666;
    transition-delay: 0.1s;
  }
  &:after {
    -webkit-text-fill-color: #fff;
    content: "sorry, your browser does not support scroll timeline";
    font-family: "Press Start 2p", sans-serif;
    text-align: center;
    font-size: 3vh;
    top: calc(50% + 20vh);
    animation: flashing 0.5s ease-in-out infinite alternate;
    @keyframes flashing {
      to {
        opacity: 0.5;
      }
    }
  }
  @supports (animation-timeline: scroll()) {
    &:after {
      content: "click anywhere to start";
      font-size: 1vh;
    }
  }
  @keyframes load {
    0%,
    50% {
      opacity: 1;
    }
    100% {
      opacity: 0;
    }
  }
}

#weapon {
  background: url("https://i.imgur.com/dpySZUG.png") 0% 20px / auto 1072px
    no-repeat;
  --scale: 5;
  position: fixed;
  z-index: 9;
  width: 90px;
  height: 154px;
  left: calc(50% + 7.5vh);
  bottom: -500px;
  transition: 0.5s ease-in-out 0.45s;
  transform-origin: bottom;
  transform: scale(var(--scale));
  animation: bounce 1s steps(4, end) infinite alternate;
  @keyframes bounce {
    to {
      transform: scale(var(--scale)) translateY(5px);
    }
  }
  @media (max-height: 768px) {
    --scale: 4;
  }
}

#hud {
  position: fixed;
  z-index: 999;
  background: #333;
  box-shadow: 0 0 0 5px #444;
  bottom: 0;
  left: 0;
  width: 100vw;
  height: clamp(25px, 7.5vh, 100px);
  transform: translateY(200%);
  transition: 0.5s ease-in-out 0.3s;
  &:before {
    content: "";
    position: absolute;
    aspect-ratio: 1/1;
    height: clamp(30px, 8vh, 125px);
    bottom: 0;
    left: 50%;
    transform: translate(-50%, 0);
    box-shadow: inset 0 0 0 1px #000, 0 0 0 5px #444;
    background: url("https://assets.codepen.io/383755/grin-doomguy.gif") 0% 50% /
        contain no-repeat,
      #666;
  }
}

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