body {
  background-color: #fff;

  background-image:
    /* тонкие горизонтали */
    repeating-linear-gradient(
      to bottom,
      transparent,
      transparent 23px,
      #e3e3e3 24px
    ),

    /* жирная линия каждые 5 */
    repeating-linear-gradient(
      to bottom,
      transparent,
      transparent 119px,
      #cfcfcf 120px
    ),

    /* вертикали */
    repeating-linear-gradient(
      to right,
      transparent,
      transparent 23px,
      #e3e3e3 24px
    );
}