@use postcss-preset-env {
  stage: 0;
}

body {
  --color-green: #58ba97;
  --color-black: #2c2421;
  --square-size: 400px;

  width: 100%;
  height: 100%;
  background-color: var(--color-green);
  background-image: 
    repeating-linear-gradient(45deg, var(--color-black) 25%, transparent 25%, transparent 75%, var(--color-black) 75%, var(--color-black)),
    repeating-linear-gradient(45deg, var(--color-black) 25%, transparent 25%, transparent 75%, var(--color-black) 75%, var(--color-black));
  background-position: 0 0, calc(var(--square-size) / 2) calc(var(--square-size) / 2);
  background-size: var(--square-size) var(--square-size);
}

body {
  height: 500vh;
}