I made this with Odin, using Clay for the layout and raylib as the renderer. Use the S key to swap between the modes, and press the small moon/sun icon in the top left corner to swap between colour modes (it is on lightmode by default).

To download the project files, run:

git clone https://github.com/scheinheiser/odin-clay-timer

Enter the directory and build the files with this:

odin build . -o:speed

After this, start the app through running the executable. This app was made purely to learn Odin more and try out Clay for the first time, I won't try to fix any bugs/issues that you might encounter. I also leaned quite heavily on this existing project to understand how some of the C code would look in Odin, so thanks to them.