Comments (0)

CSS

width: 500px;
height: 500px;
background:
  radial-gradient(ellipse at 50% 100%, rgb(0 0 0 / 1) 50%, rgb(0 0 0 / 0) 51%) 0px 355px / 500px 120px no-repeat no-repeat, /* Circular bottom mask */
  linear-gradient(0deg, rgb(0 0 0 / 1) 19.5%, rgb(255 255 255 / 0) 20%, rgb(255 255 255 / 0) 80%, rgb(0 0 0 / 1) 80.5%) 0px 0px / 500px 500px no-repeat no-repeat, /* Top/bottom mask */
  linear-gradient(-110deg, rgb(0 0 0 / 0) 42%, rgb(0 0 0 / 0.4) 45.5%, rgb(229 9 19 / 1) 46%, rgb(229 9 19 / 1) 54%, rgb(0 0 0 / 0.4) 54.5%, rgb(0 0 0 / 0) 58%) 0px 0px / 500px 500px no-repeat no-repeat, /* Diagonal */
  linear-gradient(90deg, rgb(0 0 0 / 1) 32.5%, rgb(255 255 255 / 0) 33%, rgb(0 0 0 / 0) 43.5%, rgb(0 0 0 / 1) 44%, rgb(0 0 0 / 1) 56%, rgb(0 0 0 / 0) 56.5%, rgb(255 255 255 / 0) 67%, rgb(0 0 0 / 1) 67.5%) 0px 0px / 500px 500px no-repeat no-repeat, /* Mask */
  linear-gradient(rgb(169 0 8 / 1), rgb(169 0 8 / 1)) 0px 0px / 500px 500px no-repeat no-repeat; /* Background */