on:after {
      content: '';
      position: absolute;
      left: -2px;
      top: -2px;
      border-radius: 10px;
      background: linear-gradient(45deg, #48ff00, #15ff00, #000000,#000000, #ff0000);
      background-size: 400%;
      width: calc(100% + 4px);
      height: calc(100% + 4px);
      z-index: -1;
      animation: steam 10s linear infinite;
    }

    @keyframes steam {
      0% {
        background-position: 0 0;
      }

      50% {
        background-position: 400% 0;
      }

      100% 