html, body {
  width: 100%;
  height: 100%;
}

@media (prefers-color-scheme: dark) {
    body {
        display: flex;
        margin: 0;
        padding: 0;
        font-family: '-apple-system', sans-serif;
        align-items: center;
        justify-content: center;
        background-color: black;
        perspective: 100vw;
        -webkit-text-smoothing: anti-aliased;
    }
}

@media (prefers-color-scheme: light) {
    body {
        display: flex;
        margin: 0;
        padding: 0;
        font-family: '-apple-system', sans-serif;
        align-items: center;
        justify-content: center;
        background-color: white;
        perspective: 100vw;
        -webkit-text-smoothing: anti-aliased;
    }
}

digit {
  position: relative;
  width: 7vw;
  height: 11vw;
  margin: 0 0.25vw;
  -webkit-backface-visibility: hidden;
}

/* Flip Flaps
------------------------------------------------*/
@media (prefers-color-scheme: dark) {
    flap-top,
    flap-top-flip,
    flap-bottom,
    flap-bottom-flip {
      box-sizing: border-box;
      position: absolute;
      display: flex;
      width: 100%;
      height: 50%;
      left: 0;
      justify-content: center;
      overflow: hidden;
      color: #e1e1e1;
      background-color: rgb(12,12,12);
      box-shadow: inset 0 1px 0 0 rgba(255,255,255,0.04);
      -webkit-backface-visibility: hidden;
    }
}

@media (prefers-color-scheme: light) {
    flap-top,
    flap-top-flip,
    flap-bottom,
    flap-bottom-flip {
      box-sizing: border-box;
      position: absolute;
      display: flex;
      width: 100%;
      height: 50%;
      left: 0;
      justify-content: center;
      overflow: hidden;
      color: #323232;
      background-color: rgb(200,200,200);
      box-shadow: inset 0 1px 0 0 rgba(0,0,0,0.04);
      -webkit-backface-visibility: hidden;
    }
}

flap-top,
flap-top-flip {
  top: 0;
  border-radius: 0.4vw 0.4vw 0 0;
}
flap-bottom,
flap-bottom-flip {
  bottom: 0;
  border-radius: 0 0 0.4vw 0.4vw;
}

flap-top-flip {
  display: none;
  transform-origin: 100% 100%;
  animation: flip-top-down var(--anim) ease-in;
}
flap-bottom-flip {
  display: none;
  transform-origin: 100% 0%;
  animation: flip-bottom-down var(--anim) ease-out;
}

flap-top > n,
flap-top-flip > n {
  top: 0;
}
flap-bottom > n,
flap-bottom-flip > n {
  bottom: 0;
}

@media screen and (min-width: 800px) {
  flap-top,
  flap-top-flip {
    transform: translateY(-1px);
  }
  flap-bottom,
  flap-bottom-flip {
    transform: translateY(1px);
  }
  flap-top > n,
  flap-top-flip > n {
    top: 1px;
  }
  flap-bottom > n,
  flap-bottom-flip > n {
    bottom: 1px;
  }
}

@media screen and (min-width: 1280px) {
  flap-top,
  flap-top-flip {
    transform: translateY(-2px);
  }
  flap-bottom,
  flap-bottom-flip {
    transform: translateY(2px);
  }
  flap-top > n,
  flap-top-flip > n {
    top: 2px;
  }
  flap-bottom > n,
  flap-bottom-flip > n {
    bottom: 2px;
  }
}

/* Number
------------------------------------------------*/
n {
  position: absolute;
  left: 0;
  width: 100%;
  height: 11vw;
  font-size: 9vw;
  font-weight: 200;
  line-height: 118%;
  text-align: center;
  font-variant-numeric: tabular-nums;
  -webkit-backface-visibility: hidden;
  transform: translate3d(0, 0, 0)
}

/* Animations
------------------------------------------------*/
@media (prefers-color-scheme: light) {
    @keyframes flip-top-down {
      0% {
        transform: rotateX(0);
      }
      100% {
        transform: rotateX(-90deg);
        color: gray;
        background-color: gray;
      }
    }
    @keyframes flip-bottom-down {
      0% {
        color: black;
        background-color: rgb(220,220,220);
        transform: rotateX(90deg);
      }
      100% {
        transform: rotateX(0deg);
      }
    }

    @media screen and (min-width: 800px) {
      @keyframes flip-top-down {
        0% {
          transform: translateY(-1px) rotateX(0);
        }
        100% {
          transform: translateY(-1px) rotateX(-90deg);
          color: gray;
          background-color: gray;
        }
      }
      @keyframes flip-bottom-down {
        0% {
          color: black;
          background-color: rgb(220,220,220);
          transform: translateY(1px) rotateX(90deg);
        }
        100% {
          transform: translateY(1px) rotateX(0deg);
        }
      }
    }

    @media screen and (min-width: 1280px) {
      @keyframes flip-top-down {
        0% {
          transform: translateY(-2px) rotateX(0);
        }
        100% {
          transform: translateY(-2px) rotateX(-90deg);
          color: gray;
          background-color: gray;
        }
      }
      @keyframes flip-bottom-down {
        0% {
          color: black;
          background-color: rgb(220,220,220);
          transform: translateY(2px) rotateX(90deg);
        }
        100% {
          transform: translateY(2px) rotateX(0deg);
        }
      }
    }
}

@media (prefers-color-scheme: dark) {
    @keyframes flip-top-down {
      0% {
        transform: rotateX(0);
      }
      100% {
        transform: rotateX(-90deg);
        color: black;
        background-color: black;
      }
    }
    @keyframes flip-bottom-down {
      0% {
        color: white;
        background-color: rgb(30,30,30);
        transform: rotateX(90deg);
      }
      100% {
        transform: rotateX(0deg);
      }
    }

    @media screen and (min-width: 800px) {
      @keyframes flip-top-down {
        0% {
          transform: translateY(-1px) rotateX(0);
        }
        100% {
          transform: translateY(-1px) rotateX(-90deg);
          color: black;
          background-color: black;
        }
      }
      @keyframes flip-bottom-down {
        0% {
          color: white;
          background-color: rgb(30,30,30);
          transform: translateY(1px) rotateX(90deg);
        }
        100% {
          transform: translateY(1px) rotateX(0deg);
        }
      }
    }

    @media screen and (min-width: 1280px) {
      @keyframes flip-top-down {
        0% {
          transform: translateY(-2px) rotateX(0);
        }
        100% {
          transform: translateY(-2px) rotateX(-90deg);
          color: black;
          background-color: black;
        }
      }
      @keyframes flip-bottom-down {
        0% {
          color: white;
          background-color: rgb(30,30,30);
          transform: translateY(2px) rotateX(90deg);
        }
        100% {
          transform: translateY(2px) rotateX(0deg);
        }
      }
    }
}