css_grammar = {
    '<start>': [['<stylesheet>']],
    '<stylesheet>': [[
        '<[CHARSET_SYM_STRING_SEMI]-1>', ' ', '<[S_OR_CDO_OR_CDC]-1>', ' ',
        '<[import_CDO_S_OR_CDC_S]-1>', ' ', '<[stylesheet_closing_GROUPING]-1>'
    ]],
    '<[CHARSET_SYM_STRING_SEMI]>': [['<CHARSET_SYM>', ' ', '<STRING>', ' ;']],
    '<[S_OR_CDO_OR_CDC]>': [['<Sp>'], ['<CDO>'], ['<CDC>']],
    '<[import_CDO_S_OR_CDC_S]>': [['<import>', ' ', '<[CDO_S_OR_CDC_S]-1>']],
    '<[CDO_S_OR_CDC_S]>': [['<CDO>', ' ', '<Ss>'], ['<CDC>', ' ', '<Ss>']],
    '<[ruleset_OR_media_OR_page]>': [['<ruleset>'], ['<media>'], ['<page>']],
    '<[stylesheet_closing_GROUPING]>':
    [['<[ruleset_OR_media_OR_page]>', ' ', '<[CDO_S_OR_CDC_S]-2>']],
    '<import>': [[
        '<IMPORT_SYM>', ' ', '<Ss>', ' ', '<[STRING_OR_URI]>', ' ', '<Ss>',
        ' ', '<media_list-1>', ' ; ', '<Ss>'
    ]],
    '<[STRING_OR_URI]>': [['<STRING>'], ['<URI>']],
    '<media>': [[
        '<MEDIA_SYM>', ' ', '<Ss>', ' ', '<media_list>', ' { ', '<Ss>', ' ',
        '<ruleset-1>', ' } ', '<Ss>'
    ]],
    '<media_list>': [['<medium>', ' ', '<[COMMA_S_medium]-1>']],
    '<[COMMA_S_medium]>': [[', ', '<Ss>', ' ', '<medium>']],
    '<medium>': [['<IDENT>', ' ', '<Ss>']],
    '<page>': [[
        '<PAGE_SYM>', ' ', '<Ss>', ' ', '<pseudo_page-1>', ' { ', '<Ss>', ' ',
        '<declaration-1>', ' ', '<[SEMI_S_declaration]-1>', ' } ', '<Ss>'
    ]],
    '<[SEMI_S_declaration]>': [['; ', '<Ss>', ' ', '<declaration-2>']],
    '<pseudo_page>': [[': ', '<IDENT>', ' ', '<Ss>']],
    '<operator>': [['/ ', '<Ss>'], [', ', '<Ss>']],
    '<combinator>': [['+ ', '<Ss>'], ['> ', '<Ss>']],
    '<unary_operator>': [['-'], ['+']],
    '<property>': [['<IDENT>', ' ', '<Ss>']],
    '<ruleset>': [[
        '<selector>', ' ', '<COMMA_S_selector-1>', ' { ', '<Ss>', ' ',
        '<declaration-3>', ' ', '<[SEMI_S_declaration]-2>', ' } ', '<Ss>'
    ]],
    '<COMMA_S_selector>': [[', ', '<Ss>', ' selector']],
    '<selector>':
    [['<simple_selector>', ' ', '<[combinator_selector_OR_S]-1>']],
    '<[combinator_selector]>': [['<combinator-1>', ' ', '<selector>']],
    '<[combinator_selector_OR_S]>':
    [['<combinator>', ' ', '<selector>'],
     ['<Sp>', ' ', '<[combinator_selector]-1>']],
    '<simple_selector>':
    [['<element_name>', ' ', '<[HASH_OR_class_OR_attrib_OR_pseudo]-1>'],
     ['<[HASH_OR_class_OR_attrib_OR_pseudo]-2>']],
    '<[HASH_OR_class_OR_attrib_OR_pseudo]>': [['<HASH>'], ['<class>'],
                                              ['<attrib>'], ['<pseudo>']],
    '<class>': [['.', '<IDENT>']],
    '<element_name>': [['<IDENT>'], ['*']],
    '<attrib>': [[
        '[ ', '<Ss>', ' ', '<IDENT>', ' ', '<Ss>', ' ',
        '<[attrib_GROUPING]-1>', ' ]'
    ]],
    '<[EQUAL_OR_INCLUDES_OR_DASHMATCH]>': [['='], ['<INCLUDES>'],
                                           ['<DASHMATCH>']],
    '<[IDENT_OR_STRING]>': [['<IDENT>'], ['<STRING>']],
    '<[attrib_GROUPING]>': [[
        '<[EQUAL_OR_INCLUDES_OR_DASHMATCH]>', ' ', '<Ss>', ' ',
        '<[IDENT_OR_STRING]>', ' ', '<Ss>'
    ]],
    '<pseudo>': [[': ', '<[IDENT_OR_FUNCTION]>']],
    '<[IDENT_OR_FUNCTION]>':
    [['<IDENT>'], ['<FUNCTION>', ' ', '<Ss>', ' ', '<[IDENT_S]-1>', ' )']],
    '<[IDENT_S]>': [['<IDENT>', ' ', '<Ss>']],
    '<declaration>':
    [['<property>', ' : ', '<Ss>', ' ', '<expr>', ' ', '<prio-1>']],
    '<prio>': [['<IMPORT_SYM>', ' ', '<Ss>']],
    '<expr>': [['<term>', ' ', '<[operator_term]-1>']],
    '<[operator_term]>': [['<operator-1>', ' ', '<term>']],
    '<term>': [['<unary_operator-1>', ' ', '<[term_GROUPING]>'],
               ['<STRING>', ' ', '<Ss>'], ['<IDENT>', ' ', '<Ss>'],
               ['<URI>', ' ', '<Ss>'], ['<hexcolor>'], ['<function>']],
    '<[term_GROUPING]>': [['<NUMBER>', ' ', '<Ss>'],
                          ['<PERCENTAGE>', ' ', '<Ss>'],
                          ['<LENGTH>', ' ', '<Ss>'], ['<EMS>', ' ', '<Ss>'],
                          ['<EXS>', ' ', '<Ss>'], ['<ANGLE>', ' ', '<Ss>'],
                          ['<TIME>', ' ', '<Ss>'], ['<FREQ>', ' ', '<Ss>']],
    '<function>': [['<FUNCTION>', ' ', '<Ss>', ' ', '<expr>', ' ) ', '<Ss>']],
    '<hexcolor>': [['#', '<[three_char_HEX]>', ' ', '<Ss>'],
                   ['#', '<[six_char_HEX]>', ' ', '<Ss>']],
    '<[three_char_HEX]>': [['<HEX_CHAR>', '<HEX_CHAR>', '<HEX_CHAR>']],
    '<[six_char_HEX]>': [[
        '<HEX_CHAR>', '<HEX_CHAR>', '<HEX_CHAR>', '<HEX_CHAR>', '<HEX_CHAR>',
        '<HEX_CHAR>'
    ]],
    '<HEX_CHAR>': [['0'], ['1'], ['2'], ['3'], ['4'], ['5'], ['6'], ['7'],
                   ['8'], ['9'], ['a'], ['b'], ['c'], ['d'], ['e'], ['f']],
    '<Sp>': [['<WHITESPACE-1>']],
    '<Ss>': [['<WHITESPACE-2>']],
    '<So>': [[], ['<WHITESPACE>']],
    '<CDO>': [['<!--']],
    '<CDC>': [['-->']],
    '<INCLUDES>': [['~=']],
    '<DASHMATCH>': [['|=']],
    '<STRING>': [['<string1>'], ['<string2>']],
    '<IDENT>': [['<{ident}>']],
    '<HASH>': [['#', '<{name}>']],
    '<IMPORT_SYM>': [['@import']],
    '<PAGE_SYM>': [['@page']],
    '<MEDIA_SYM>': [['@media']],
    '<CHARSET_SYM>': [['@charset']],
    '<EMS>': [['<{num}>', 'em']],
    '<EXS>': [['<{num}>', 'ex']],
    '<LENGTH>': [['<{num}>', 'px'], ['<{num}>', 'cm'], ['<{num}>', 'mm'],
                 ['<{num}>', 'in'], ['<{num}>', 'pt'], ['<{num}>', 'pc']],
    '<ANGLE>': [['<{num}>', 'deg'], ['<{num}>', 'rad'], ['<{num}>', 'grad']],
    '<TIME>': [['<{num}>', 'ms'], ['<{num}>', 's']],
    '<FREQ>': [['<{num}>', 'hz'], ['<{num}>', 'khz']],
    '<PERCENTAGE>': [['<{num}>', '%']],
    '<NUMBER>': [['<{num}>']],
    '<URI>': [['url("', '<So>', '<url>', '<So>', '")'],
              ['url("', '<So>', '<STRING>', '<So>', '")']],
    '<url>': [['<url_-1>']],
    '<url_>': [['!'], ['#'], ['$'], ['%'], ['&'], ['*'], ['-'], ['~'],
               ['<escape>']],
    '<FUNCTION>': [['<{ident}>', '(']],
    '<string1>': [['"', '<qmychars1-1>', '"']],
    '<string2>': [["'", '<qmychars2-1>', "'"]],
    '<qnonl1>': [['7'], ['Q'], ['J'], ['@'], ['2'], ['g'], ['\t'], ['X'],
                 ['`'], ['G'], ['e'], ['['], ['?'], ['v'], ['$'], ['j'], ['K'],
                 ['d'], ['A'], ['n'], ['h'], ['l'], ['4'], ['D'], ['a'], ['#'],
                 ['f'], ['y'], ['B'], ['U'], ['P'], ['3'], ['O'], ['S'], [')'],
                 [' '], ['W'], ['o'], ['b'], ['|'], ['q'], ['L'], [']'], ['V'],
                 ['*'], ['z'], ['}'], ['6'], ['u'], ['^'], [','], ['N'], ['>'],
                 ['+'], ['Y'], ['t'], ['k'], ['!'], ['p'], ['Z'], ['E'], ['('],
                 ['\\'], ['<'], ['F'], ['%'], ['9'], ['0'], ['s'], [';'],
                 ['&'], ['C'], ['T'], ['r'], ['5'], ['R'], ["'"], ['_'], ['.'],
                 ['8'], ['H'], ['i'], ['/'], ['M'], ['~'], ['{'], [':'], ['c'],
                 ['I'], ['-'], ['\x0b'], ['1'], ['w'], ['x'], ['m'], ['=']],
    '<qnonl2>': [['7'], ['Q'], ['J'], ['@'], ['2'], ['g'], ['\t'], ['X'],
                 ['`'], ['G'], ['e'], ['['], ['?'], ['v'], ['$'], ['j'], ['K'],
                 ['d'], ['A'], ['n'], ['h'], ['l'], ['4'], ['D'], ['a'], ['#'],
                 ['f'], ['y'], ['B'], ['U'], ['P'], ['3'], ['O'], ['S'], [')'],
                 [' '], ['W'], ['o'], ['b'], ['|'], ['q'], ['L'], [']'], ['V'],
                 ['*'], ['z'], ['}'], ['6'], ['u'], ['^'], [','], ['N'], ['>'],
                 ['+'], ['Y'], ['t'], ['k'], ['!'], ['p'], ['Z'], ['E'], ['('],
                 ['\\'], ['<'], ['F'], ['%'], ['9'], ['0'], ['s'], [';'],
                 ['&'], ['C'], ['T'], ['r'], ['5'], ['"'], ['R'], ['_'], ['.'],
                 ['8'], ['H'], ['i'], ['/'], ['M'], ['~'], ['{'], [':'], ['c'],
                 ['I'], ['-'], ['\x0b'], ['1'], ['w'], ['x'], ['m'], ['=']],
    '<qmychars1>': [['<qnonl1>'], ['\\', '<nl>'], ['<escape>']],
    '<qmychars2>': [['<qnonl2>'], ['\\', '<nl>'], ['<escape>']],
    '<nl>': [['\r'], ['\n'], ['\x0c'], ['\r\n']],
    '<escape>': [['\\', '<echar>']],
    '<echar>': [['Q'], ['J'], ['@'], ['g'], ['\t'], ['X'], ['`'], ['G'], ['['],
                ['?'], ['v'], ['$'], ['j'], ['K'], ['A'], ['n'], ['h'], ['l'],
                ['D'], ['#'], ['y'], ['B'], ['U'], ['P'], ['O'], ['S'], [')'],
                [' '], ['W'], ['o'], ['|'], ['q'], ['L'], [']'], ['V'], ['*'],
                ['z'], ['}'], ['u'], ['^'], [','], ['N'], ['>'], ['+'], ['Y'],
                ['t'], ['k'], ['!'], ['p'], ['Z'], ['E'], ['('], ['\\'], ['<'],
                ['F'], ['%'], ['s'], [';'], ['&'], ['C'], ['T'], ['r'], ['"'],
                ['R'], ["'"], ['_'], ['.'], ['H'], ['i'], ['/'], ['M'], ['~'],
                ['{'], [':'], ['I'], ['-'], ['\x0b'], ['w'], ['x'], ['m'],
                ['=']],
    '<{ident}>': [['<minus-1>', '<nmstart>', '<nmchar-1>']],
    '<nmstart>': [['a'], ['b'], ['c'], ['d'], ['e'], ['f'], ['g'], ['h'],
                  ['i'], ['j'], ['k'], ['l'], ['m'], ['n'], ['o'], ['p'],
                  ['q'], ['r'], ['s'], ['t'], ['u'], ['v'], ['w'], ['x'],
                  ['y'], ['z'], ['<escape>'], ['_']],
    '<nmchar>': [['a'], ['b'], ['c'], ['d'], ['e'], ['f'], ['g'], ['h'], ['i'],
                 ['j'], ['k'], ['l'], ['m'], ['n'], ['o'], ['p'], ['q'], ['r'],
                 ['s'], ['t'], ['u'], ['v'], ['w'], ['x'], ['y'], ['z'], ['0'],
                 ['1'], ['2'], ['3'], ['4'], ['5'], ['6'], ['7'], ['8'], ['9'],
                 ['<escape>'], ['_'], ['-']],
    '<minus>': [['-']],
    '<{name}>': [['<nmchar-2>']],
    '<{num}>': [['<INTEGER>']],
    '<WHITESPACE>': [[' '], ['\t']],
    '<INTEGER>': [['<DIGIT>', '<INTEGER>'], ['<DIGIT>']],
    '<DIGIT>': [['0'], ['1'], ['2'], ['3'], ['4'], ['5'], ['6'], ['7'], ['8'],
                ['9']],
    '<[CHARSET_SYM_STRING_SEMI]-1>': [[], ['<[CHARSET_SYM_STRING_SEMI]>']],
    '<[S_OR_CDO_OR_CDC]-1>': [[],
                              ['<[S_OR_CDO_OR_CDC]>',
                               '<[S_OR_CDO_OR_CDC]-1>']],
    '<[import_CDO_S_OR_CDC_S]-1>':
    [[], ['<[import_CDO_S_OR_CDC_S]>', '<[import_CDO_S_OR_CDC_S]-1>']],
    '<[stylesheet_closing_GROUPING]-1>':
    [[],
     ['<[stylesheet_closing_GROUPING]>', '<[stylesheet_closing_GROUPING]-1>']],
    '<[CDO_S_OR_CDC_S]-1>': [[],
                             ['<[CDO_S_OR_CDC_S]>', '<[CDO_S_OR_CDC_S]-1>']],
    '<[CDO_S_OR_CDC_S]-2>': [[],
                             ['<[CDO_S_OR_CDC_S]>', '<[CDO_S_OR_CDC_S]-2>']],
    '<media_list-1>': [[], ['<media_list>']],
    '<ruleset-1>': [[], ['<ruleset>', '<ruleset-1>']],
    '<[COMMA_S_medium]-1>': [[],
                             ['<[COMMA_S_medium]>', '<[COMMA_S_medium]-1>']],
    '<pseudo_page-1>': [[], ['<pseudo_page>']],
    '<declaration-1>': [[], ['<declaration>']],
    '<[SEMI_S_declaration]-1>':
    [[], ['<[SEMI_S_declaration]>', '<[SEMI_S_declaration]-1>']],
    '<declaration-2>': [[], ['<declaration>']],
    '<COMMA_S_selector-1>': [[],
                             ['<COMMA_S_selector>', '<COMMA_S_selector-1>']],
    '<declaration-3>': [[], ['<declaration>']],
    '<[SEMI_S_declaration]-2>':
    [[], ['<[SEMI_S_declaration]>', '<[SEMI_S_declaration]-2>']],
    '<[combinator_selector_OR_S]-1>': [[], ['<[combinator_selector_OR_S]>']],
    '<combinator-1>': [[], ['<combinator>']],
    '<[combinator_selector]-1>': [[], ['<[combinator_selector]>']],
    '<[HASH_OR_class_OR_attrib_OR_pseudo]-1>':
    [[],
     [
         '<[HASH_OR_class_OR_attrib_OR_pseudo]>',
         '<[HASH_OR_class_OR_attrib_OR_pseudo]-1>'
     ]],
    '<[HASH_OR_class_OR_attrib_OR_pseudo]-2>':
    [['<[HASH_OR_class_OR_attrib_OR_pseudo]>'],
     [
         '<[HASH_OR_class_OR_attrib_OR_pseudo]>',
         '<[HASH_OR_class_OR_attrib_OR_pseudo]-2>'
     ]],
    '<[attrib_GROUPING]-1>': [[], ['<[attrib_GROUPING]>']],
    '<[IDENT_S]-1>': [[], ['<[IDENT_S]>']],
    '<prio-1>': [[], ['<prio>']],
    '<[operator_term]-1>': [[], ['<[operator_term]>', '<[operator_term]-1>']],
    '<operator-1>': [[], ['<operator>']],
    '<unary_operator-1>': [[], ['<unary_operator>']],
    '<WHITESPACE-1>': [['<WHITESPACE>'], ['<WHITESPACE>', '<WHITESPACE-1>']],
    '<WHITESPACE-2>': [[], ['<WHITESPACE>', '<WHITESPACE-2>']],
    '<url_-1>': [[], ['<url_>', '<url_-1>']],
    '<qmychars1-1>': [[], ['<qmychars1>', '<qmychars1-1>']],
    '<qmychars2-1>': [[], ['<qmychars2>', '<qmychars2-1>']],
    '<minus-1>': [[], ['<minus>']],
    '<nmchar-1>': [[], ['<nmchar>', '<nmchar-1>']],
    '<nmchar-2>': [['<nmchar>'], ['<nmchar>', '<nmchar-2>']]
}