.snake-border {
    background: linear-gradient(90deg, #8A2BE2, #4B0082, #8A2BE2, #4B0082, #8A2BE2, #4B0082);
    background-size: 400% 400%;
    -webkit-animation: AnimationName 20s ease infinite;
    -moz-animation: AnimationName 20s ease infinite;
    animation: AnimationName 20s ease infinite;
  }

  .number-box {
    position: absolute;
    top: 10px;
    right: 10px;
    width: 25px;
    height: 25px;
    background-color: #9457d0;
    color: white;
    font-size: 14px;
    text-align: center;
    line-height: 25px;
    font-weight: bold;
  }

  @-webkit-keyframes AnimationName {
    0% {
      background-position: 0% 50%
    }

    50% {
      background-position: 100% 50%
    }

    100% {
      background-position: 0% 50%
    }
  }

  @-moz-keyframes AnimationName {
    0% {
      background-position: 0% 50%
    }

    50% {
      background-position: 100% 50%
    }

    100% {
      background-position: 0% 50%
    }
  }

  @keyframes AnimationName {
    0% {
      background-position: 0% 50%
    }

    50% {
      background-position: 100% 50%
    }

    100% {
      background-position: 0% 50%
    }
  }