Cell[StyleData["InlineCell"],
ShowAutoStyles->True,
ShowCodeAssist->True,
LanguageCategory->"Mathematica",
FormatType->"InputForm",
FontFamily->"Courier New",
FontWeight->"Bold"]

SetOptions[
    EvaluationNotebook[],
    StyleDefinitions -> Notebook[
        {
        Cell[StyleData[StyleDefinitions -> "Default.nb"]],
        Cell[StyleData["Text"], DefaultInlineFormatType -> System`DefaultInputInlineFormatType],
        Cell[StyleData["InlineCell", StyleDefinitions->StyleData["Input"]]]
        }
    ]
]