Parent function for setting notebook, text/md, and
    codecell font-properties

def set_font_properties(style_less,
                        nbfont=None,
                        tcfont=None,
                        monofont=None,
                        monosize=11,
                        tcfontsize=13,
                        nbfontsize=13,
                        prfontsize=95,
                        dffontsize=93,
                        outfontsize=85,
                        mathfontsize=100,
                        dfonts=False):
    """Parent function for setting notebook, text/md, and
    codecell font-properties
    """

    fontsizes = [monosize, nbfontsize, tcfontsize, prfontsize, dffontsize, outfontsize]
    monosize, nbfontsize, tcfontsize, prfontsize, dffontsize, outfontsize = convert_fontsizes(fontsizes)
    if dfonts==True:
        monofont, tcfont, nbfont = ['monospace', 'sans-serif', 'sans-serif']
    else:
        if monofont is not None:
            monofont, monofpath = stored_font_dicts(monofont)
            style_less = import_fonts(style_less, monofont, monofpath)
        else:
            monofont='monospace'
        if tcfont is not None:
            tcfont, tcfontpath = stored_font_dicts(tcfont)
            style_less = import_fonts(style_less, tcfont, tcfontpath)
        else:
            tcfont='sans-serif'
        if nbfont is not None:
            if nbfont == 'proxima':
                nbfont, tcfont = ["'Proxima Nova'"]*2
                style_less = proxima_nova_imports(style_less)
            else:
                nbfont, nbfontpath = stored_font_dicts(nbfont)
                style_less = import_fonts(style_less, nbfont, nbfontpath)
        else:
            nbfont='sans-serif'

    style_less += '/* Set Font-Type and Font-Size Variables  */\n'
    # font names and fontfamily info for codecells, notebook & textcells
    style_less += '@monofont: {}; \n'.format(monofont)
    style_less += '@notebook-fontfamily: {}; \n'.format(nbfont)
    style_less += '@text-cell-fontfamily: {}; \n'.format(tcfont)
    # font size for codecells, main notebook, notebook-sub, & textcells
    style_less += '@monofontsize: {}pt; \n'.format(monosize)
    style_less += '@monofontsize-sub: {}pt; \n'.format(float(monosize) - 1)
    style_less += '@nb-fontsize: {}pt; \n'.format(nbfontsize)
    style_less += '@nb-fontsize-sub: {}pt; \n'.format(float(nbfontsize) - 1)
    style_less += '@text-cell-fontsize: {}pt; \n'.format(tcfontsize)
    style_less += '@df-header-fontsize: {}pt; \n'.format(float(dffontsize) + 1)
    style_less += '@df-fontsize: {}pt; \n'.format(dffontsize)
    style_less += '@output-font-size: {}pt; \n'.format(outfontsize)
    style_less += '@prompt-fontsize: {}pt; \n'.format(prfontsize)
    style_less += '@mathfontsize: {}%; \n'.format(mathfontsize)
    style_less += '\n\n'
    style_less += '/* Import Theme Colors and Define Layout Variables */\n'
    return style_less