---
title: NSButton.GradientType.concaveStrong
framework: appkit
role: symbol
role_heading: Case
path: appkit/nsbutton/gradienttype/concavestrong
---

# NSButton.GradientType.concaveStrong

As with NSGradientConcaveWeak, the top-left corner is light gray, and the bottom-right corner is dark gray, but the difference between the grays is greater, so the appearance of being pushed in is stronger.

## Declaration

```swift
case concaveStrong
```

## See Also

### Constants

- [NSButton.GradientType.none](appkit/nsbutton/gradienttype/none.md)
- [NSButton.GradientType.concaveWeak](appkit/nsbutton/gradienttype/concaveweak.md)
- [NSButton.GradientType.convexWeak](appkit/nsbutton/gradienttype/convexweak.md)
- [NSButton.GradientType.convexStrong](appkit/nsbutton/gradienttype/convexstrong.md)