Theme.kt

private val DarkColorPalette = darkColors(
        primary = purple200,
        primaryVariant = purple700,
        secondary = teal200
)

private val LightColorPalette = lightColors(
        primary = purple500,
        primaryVariant = purple700,
        secondary = teal200

        /* Other default colors to override
    background = Color.White,
    surface = Color.White,
    onPrimary = Color.White,
    onSecondary = Color.Black,
    onBackground = Color.Black,
    onSurface = Color.Black,
    */
)

@Composable
fun MyApplicationTheme(darkTheme: Boolean = isSystemInDarkTheme(), content: @Composable() () -> Unit) {
    val colors = if (darkTheme) {
        DarkColorPalette
    } else {
        LightColorPalette
    }

    MaterialTheme(
            colors = colors,
            typography = typography,
            shapes = shapes,
            content = content
    )
}