message: docs(css-utilities): document display css utils
diff: @@ -178,6 +178,43 @@ The table below shows the default behavior, where `{modifier}` is any of the fol
  | `float-lg-{modifier}` | Applies the modifier to the element when `min-width: 992px`. |
  | `float-xl-{modifier}` | Applies the modifier to the element when `min-width: 1200px`. |
  +## Element Display
  +
  +The display CSS property determines if an element should be visible or not. The element will still be in the DOM, but not rendered, if it is hidden.
  +
  +```html
  +<ion-grid>
  + <ion-row>
  + <ion-col class="ion-hide">
  + <div>
  + <h3>hidden</h3>
  + You can't see me.
  + </div>
  + </ion-col>
  + <ion-col>
  + <div>
  + <h3>not-hidden</h3>
  + You can see me!
  + </div>
  + </ion-col>
  + </ion-row>
  +</ion-grid>
  +```
  +
  +| Class | Style Rule | Description |
  +|---------------|---------------------------------|-----------------------------------------------------------------------------------------------------------|
  +| `.ion-hide` | `display: none` | The element will be hidden.
  +
  +### Responsive Display Attributes
  +
  +There are also additional classes to modify the visibility based on the screen size. Instead of just `.ion-hide` for all screen sizes, use `.ion-hide-{breakpoint}-{dir}` to only use the class on specific screen sizes, where `{breakpoint}` is one of the breakpoint names listed in [Ionic Breakpoints](#ionic-breakpoints), and `{dir}` is whether the element should be hidden on all screen sizes above (`up`) or below (`down`) the specified breakpoint.
  +
  +| Class | Description |
  +|------------------------|--------------------------------------------------------------------------------------------------------------|
  +| `.ion-hide-sm-{dir}` | Applies the modifier to the element when `min-width: 576px` (`up`) or `max-width: 576px` (`down`). |
  +| `.ion-hide-md-{dir}` | Applies the modifier to the element when `min-width: 768px` (`up`) or `max-width: 768px` (`down`). |
  +| `.ion-hide-lg-{dir}` | Applies the modifier to the element when `min-width: 992px` (`up`) or `max-width: 992px` (`down`). |
  +| `.ion-hide-xl-{dir}` | Applies the modifier to the element when `min-width: 1200px` (`up`) or `max-width: 1200px` (`down`). |
  ## Content Space
  