Proposal: Provide a Card control or CardStyle in WinUI 3

Proposal: Provide a Card Control or a CardStyle

Summary

Currently there are no card control or a card style that developers can readily use as defined here. We only have few styles like card stroke, card fill colour etc but not a complete style that also incorporate elevation of 8.

Rationale

• Allows developer to easily implement cards matching fluent design

Open Questions

Should there be a Card Control or a Card Style on a Border?

[jp-weber]

A custom Card control is really great implemented in the PowerToys app, but it needed some further improvements (Setting, SettingExpander, e.g.): https://github.com/microsoft/PowerToys/tree/main/src/settings-ui/Settings.UI/Controls

It would be great if Card control is implemented in WinUI, because there are already a few things to adjust for the content.

[ozanyasindogan]

Basically adding these property values and styles to a grid/stackpanel-like content presenter actually does the job;

<StackPanel 
                    CornerRadius="8"
                    Padding="12"
                    BorderThickness="1"
                    BorderBrush="{ThemeResource CardStrokeColorDefaultBrush}"
                    Background="{ThemeResource CardBackgroundFillColorDefaultBrush}">