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_[Demo and API docs](https://elements.polymer-project.org/elements/paper-header-panel)_
##<paper-header-panel>
`paper-header-panel` contains a header section and a content panel section.
__Important:__ The `paper-header-panel` will not display if its parent does not have a height.
Using layout classes, you can make the `paper-header-panel` fill the screen
```html
Hello World!
```
Special support is provided for scrolling modes when one uses a paper-toolbar or equivalent for the
header section.
Example:
```html
Header
Content goes here...
```
If you want to use other than `paper-toolbar` for the header, add `paper-header` class to that
element.
Example:
```html
Content goes here...
```
To have the content fit to the main area, use the `fit` class.
```html
content fits 100% below the header
```
### Modes
Controls header and scrolling behavior. Options are `standard`, `seamed`, `waterfall`, `waterfall-tall`, `scroll` and
`cover`. Default is `standard`.
| Mode | Description |
| --- | --- |
| `standard` | The header is a step above the panel. The header will consume the panel at the point of entry, preventing it from passing through to the opposite side. |
| `seamed` | The header is presented as seamed with the panel. |
| `waterfall` | Similar to standard mode, but header is initially presented as seamed with panel, but then separates to form the step. |
| `waterfall-tall` | The header is initially taller (`tall` class is added to the header). As the user scrolls, the header separates (forming an edge) while condensing (`tall` class is removed from the header). |
| `scroll` | The header keeps its seam with the panel, and is pushed off screen. |
| `cover` | The panel covers the whole `paper-header-panel` including the header. This allows user to style the panel in such a way that the panel is partially covering the header. |
Example:
```html
content fits 100% below the header
```
### Styling
To change the shadow that shows up underneath the header:
```css
paper-header-panel {
--paper-header-panel-shadow: {
height: 6px;
bottom: -6px;
box-shadow: inset 0px 5px 6px -3px rgba(0, 0, 0, 0.4);
};
}
```
To change the panel container in different modes:
```css
paper-header-panel {
--paper-header-panel-standard-container: {
border: 1px solid gray;
};
--paper-header-panel-seamed-container: {
border: 1px solid gray;
};
--paper-header-panel-waterfall-container: {
border: 1px solid gray;
};
--paper-header-panel-waterfall-tall-container: {
border: 1px solid gray;
};
--paper-header-panel-scroll-container: {
border: 1px solid gray;
};
--paper-header-panel-cover-container: {
border: 1px solid gray;
};
}
```
The following custom properties and mixins are available for styling:
| Custom property | Description | Default |
| --- | --- | --- |
| `--paper-header-panel` | Mixin applied to the element | `{}` |
| `--paper-header-panel-body` | Mixin applied to the element's body (i.e. everything below the toolbar) | `{}` |
| `--paper-header-panel-scroll-container` | Mixin applied to the container when in scroll mode | `{}` |
| `--paper-header-panel-cover-container` | Mixin applied to the container when in cover mode | `{}` |
| `--paper-header-panel-standard-container` | Mixin applied to the container when in standard mode | `{}` |
| `--paper-header-panel-seamed-container` | Mixin applied to the container when in seamed mode | `{}` |
| `--paper-header-panel-waterfall-container` | Mixin applied to the container when in waterfall mode | `{}` |
| `--paper-header-panel-waterfall-tall-container` | Mixin applied to the container when in tall waterfall mode | `{}` |
| `--paper-header-panel-shadow` | Mixin applied to the waterfall shadow | `{}` |