Version:           0.5 (using Devel)
Installed from:    Compiled sources
Compiler:          gcc (GCC) 4.2.4 20080512 (prerelease) 
OS:                Linux

When I set the default color style of the windows to a black one, then the numbers that are in the toolbar disapear becouse their fonts are black too.

I'm attaching some screenshots. And a posible solution for this issue, if ksudoku can know the color of the base window then it could be set the color of the fonts to the contrast color of the background. I hope that code can help. BTW great job with this game, thanks ;)

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KColorScheme systemColorScheme(QPalette::Active);

// this is the background color of the window
QColor baseWndColor = systemColorScheme.background(KColorScheme::NormalBackground).color();

// we obtain the luminance
int luminance = 0.2126*baseWndColor.red() + 0.7152*baseWndColor.green() + 0.0722*baseWndColor.blue();

//we choose the color font to be
//white or black according to the luminence of the background
if (luminance > (255 / 2.0))
{
// set the color of the font to black
}
else
{
// set the color of the font to white
}

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