Aplicar cores e fontes no projeto

[Crystyanno]

        --primary-gold: #D4A842;
        --secondary-gold: #F4D77C;
        --dark-gray: #4A4A4A;
        --light-gray: #F8F9FA;
        --white: #FFFFFF;
        --text-dark: #2C2C2C;
        --shadow: rgba(212, 168, 66, 0.1);

Fontes:

import 'package:google_fonts/google_fonts.dart';

ThemeData(
textTheme: GoogleFonts.robotoTextTheme(),
),

Text(
'This is Google Fonts',
style: GoogleFonts.roboto(),
),

TextStyle(
fontFamily: 'Roboto',
fontSize: 18,
fontVariations: [
FontVariation('ital', 0),
FontVariation('wdth', 100),
FontVariation('wght', ),
FontVariation('ital', 1),
FontVariation('wdth', 100),
FontVariation('wght', )
],
),