Notepad++ Dockerfile color scheme for gray (#3F3F3F) background.

useDefineLang.xml

<NotepadPlus>
    <UserLang name="Dockerfile" ext="Dockerfile" udlVersion="2.1">
        <Settings>
            <Global caseIgnored="no" allowFoldOfComments="no" foldCompact="no" forcePureLC="0" decimalSeparator="0" />
            <Prefix Keywords1="no" Keywords2="no" Keywords3="no" Keywords4="no" Keywords5="no" Keywords6="no" Keywords7="no" Keywords8="no" />
        </Settings>
        <KeywordLists>
            <Keywords name="Comments">03 04 00# 01 02</Keywords>
            <Keywords name="Numbers, prefix1"></Keywords>
            <Keywords name="Numbers, prefix2"></Keywords>
            <Keywords name="Numbers, extras1"></Keywords>
            <Keywords name="Numbers, extras2"></Keywords>
            <Keywords name="Numbers, suffix1"></Keywords>
            <Keywords name="Numbers, suffix2"></Keywords>
            <Keywords name="Numbers, range"></Keywords>
            <Keywords name="Operators1"></Keywords>
            <Keywords name="Operators2"></Keywords>
            <Keywords name="Folders in code1, open"></Keywords>
            <Keywords name="Folders in code1, middle"></Keywords>
            <Keywords name="Folders in code1, close"></Keywords>
            <Keywords name="Folders in code2, open"></Keywords>
            <Keywords name="Folders in code2, middle"></Keywords>
            <Keywords name="Folders in code2, close"></Keywords>
            <Keywords name="Folders in comment, open"></Keywords>
            <Keywords name="Folders in comment, middle"></Keywords>
            <Keywords name="Folders in comment, close"></Keywords>
            <Keywords name="Keywords1">ADD ARG COPY CMD ENTRYPOINT ENV EXPOSE FROM LABEL MAINTAINER ONBUILD RUN USER VOLUME WORKDIR</Keywords>
            <Keywords name="Keywords2"></Keywords>
            <Keywords name="Keywords3"></Keywords>
            <Keywords name="Keywords4"></Keywords>
            <Keywords name="Keywords5"></Keywords>
            <Keywords name="Keywords6"></Keywords>
            <Keywords name="Keywords7"></Keywords>
            <Keywords name="Keywords8"></Keywords>
            <Keywords name="Delimiters">00&quot; 01 02&quot; 03' 04 05' 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23</Keywords>
        </KeywordLists>
        <Styles>
            <WordsStyle name="DEFAULT" fgColor="DCDCDC" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="COMMENTS" fgColor="7F9F7F" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="LINE COMMENTS" fgColor="7F9F7F" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="NUMBERS" fgColor="008000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS1" fgColor="FF8040" bgColor="3F3F3F" fontName="" fontStyle="1" nesting="0" />
            <WordsStyle name="KEYWORDS2" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS3" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS4" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS5" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS6" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS7" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="KEYWORDS8" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="OPERATORS" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="FOLDER IN CODE1" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="FOLDER IN CODE2" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="FOLDER IN COMMENT" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS1" fgColor="C89191" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS2" fgColor="C89191" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS3" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS4" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS5" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS6" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS7" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
            <WordsStyle name="DELIMITERS8" fgColor="000000" bgColor="3F3F3F" fontName="" fontStyle="0" nesting="0" />
        </Styles>
    </UserLang>
</NotepadPlus>

Save this file in: %APPDATA%\Roaming\Notepad++\userDefineLang.xml.