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                <div class="impossible"></div>


                $white: #ffffff;
$black: #444444;
$blue-gray: #b5c4d9;

*, *:before, *:after {
  padding: 0;
  margin: 0;
  box-sizing: border-box;

body {
  height: 100vh;
  width: 100vw;
  position: relative;
  z-index: 1;
  background: linear-gradient(-90deg, lighten($blue-gray, 10%) 15%, lighten($blue-gray, 5%) 100%);

div.impossible {
    width: 100vmin;
    height: 100vmin;
    top: -15vmin;
    left: 5vmin;
    //transform-origin: 46% 67%;
    //animation: rotatetriangle 20s linear infinite;
    position: relative;  
    display: flex;
    position: relative; 
    justify-content: center;
    align-items: center; 
    margin: 0 auto;

   /* bottom-dark */ linear-gradient(60deg, $black 0vmin, $black 38vmin, transparent 38vmin) 20vmin 77vmin / 80vmin 7.5vmin no-repeat,

   /* bottom-mid */ linear-gradient(-120deg, lighten($black, 40%) 0vmin, lighten($black, 40%) 50vmin, transparent 50vmin) -9.5vmin 84.5vmin / 80vmin 7.5vmin no-repeat,

   /* right-light */ linear-gradient(60deg, transparent 18.5vmin, $white 18.5vmin, $white 25vmin, transparent 25vmin) 50vmin 25vmin / 50vmin 60vmin no-repeat,   
    linear-gradient(120deg, $white 0vmin, $white 3.5vmin, transparent 3.5vmin) 75vmin 85vmin / 10vmin 10vmin no-repeat,
      linear-gradient(-120deg, $white 0vmin, $white 3vmin, transparent 3vmin) 65vmin 85vmin / 10vmin 10vmin no-repeat,

   /* left-light */ linear-gradient(-60deg, transparent 18.5vmin, $white 18.5vmin, $white 25vmin, transparent 25vmin) 0vmin 25vmin / 50vmin 60vmin no-repeat,

    /* left-dark */ linear-gradient(-60deg, transparent 18.5vmin, $black 18.5vmin, $black 32vmin, transparent 32vmin) 0vmin 35vmin / 50vmin 50vmin no-repeat,

    /* right-mid */ linear-gradient(60deg, transparent 18.5vmin, lighten($black, 40%) 18.5vmin, lighten($black, 40%) 25vmin, transparent 25vmin) 46.5vmin 34vmin / 50vmin 58vmin no-repeat;

 @keyframes rotatetriangle {
   0% {
     transform: rotate(0deg);
  100% {
     transform: rotate(360deg);


                /* This entry for #divtober 2023 is for impossible. The Penrose Triangle is an impossible triangle that I first became fascinated by in the works of M. C. Escher.   */