index.js

var css = require('sheetify')

var cl = css`
  :host {
    background: red;

    &:hover {
      background: green;
    }
  }
`

package.json

{
  "sheetify": {
    "transform": [
      "sheetify-nested"
    ]
  },
  "dependencies": {
    "bankai": "^9.0.0-rc8",
    "sheetify-nested": "^1.0.2"
  }
}