Nastavování barev

x1=-10;x2=-x1;
y1=-10;y2=-y1;

tloustka=0.005;
velikostbodu=0.02;

cara=Line[{{-10,-7},{10,-7}}];
kruznice=Circle[{0,0},0.4x2];
Manipulate[Deploy[
barva=RGBColor[cervena,zelena,modra];
Show[
Graphics[{
{barva,Thickness[tloustka],cara},
{barva,Thickness[tloustka],kruznice},
Text[Style["Text napsaný nastavenou barvou!",velikostpisma,barva,FontFamily->Times],{0,0},{Center,Center}]
}],
FormatType->StandardForm,AspectRatio->Automatic,PlotRange->{{x1,x2},{y1,y2}},ImageSize->300]],

{{cervena,0,Style["červená",15,Red]},0,1,0.001,Appearance->"Labeled"},
{{zelena,0,Style["zelená",15,Green]},0,1,0.001,Appearance->"Labeled"},
{{modra,0,Style["modrá",15,Blue]},0,1,0.001,Appearance->"Labeled"},
Delimiter,
{{tloustka,0.005,Style["tloušťka",15,Black]},0,0.1,0.0001,Appearance->"Labeled"},
{{velikostpisma,10,Style["velikost písma",15,Black]},1,50,1,Appearance->"Labeled"},
Delimiter,
Dynamic[Item[Style[StringJoin["RGBColor[",ToString[cervena],",",ToString[zelena],",",ToString[modra],"]"],15,Black]]],

ControlPlacement->Left,
FrameLabel->{Style["© Jaroslav Reichl, 2008",10,Black,FontFamily->Times],"",Style["Nastavování barev",25,Black,FontFamily->Times],""}]