message: docs(theme): add z-index documentation
diff: @@ -275,6 +275,31 @@ export default {
  For a component like this: `<Box w={4} h={3} />` will generate an empty `div`
  with width set to `1rem` or `16px` and height set to `0.75rem` or `12px`
  +## Z-Index
  +
  +Chakra provides some zIndex values out of the box to control the stacking order
  +of components.
  +
  +```js
  +export default {
  + zIndices: {
  + hide: -1,
  + auto: "auto",
  + base: 0,
  + docked: 10,
  + dropdown: 1000,
  + sticky: 1100,
  + banner: 1200,
  + overlay: 1300,
  + modal: 1400,
  + popover: 1500,
  + skipLink: 1600,
  + toast: 1700,
  + tooltip: 1800,
  + },
  +};
  +```
  +
  ## Icons
  All Chakra icons are stored in the theme object under the `icons` key.
  