The Aqua Light Slate VCL Style is one of the free styles available in RAD Studio. Once installed you will find this in your styles folder:
To install Aqua Light Slate VCL Style, launch RAD Studio, then go Tools ➜ GetIt Package Manager, and you will find Aqua Light Slate 2 VCL Style 1.0.
You can apply the style to your VCL applications by visiting Project ➜ Options ➜ Application ➜ Appearance, and adding the Aqua Light Slate 2 style to your project, and optionally setting it as the default. At runtime, you can change styles with the code:
Here is a preview of the style.