
  .test-9 {
    &:is(.t9-, &.t9--) {
      background-color: green;
    }
  }

  .test-10 {
    & {
      background-color: red;
    }
    background-color: green;
  }

  .test-11 {
    & {
      background-color: red;
    }
    background-color: green !important;
  }

  /* & at top level counts as :scope, i.e. the root element here */
  & .test-12 {
    background-color: green;
  }
  & > .test-12 {
    background-color: red !important;
  }

  body * + * {
    margin-top: 8px;
  }
</style>
<body>
  <p>Test