Subtitle & Axis Title Styling

from canvas.color import Color
from dataviz import Plot, save
from dataviz.core.theme import Theme


def main() raises:
    var quarters: List[String] = ["Q1", "Q2", "Q3", "Q4"]
    var revenue: List[Float64] = [42.0, 48.0, 55.0, 61.0]

    var plot = (
        Plot()
        .mark_bar()
        .encode_categorical(x=quarters, y=revenue)
        .labels(
            title="Quarterly Revenue",
            subtitle="Fiscal year 2025, in millions",
            y_title="Revenue ($M)",
        )
        .theme(
            Theme(
                subtitle_font_size=11.0,
                subtitle_color=Color(160, 160, 160),
                axis_title_font_size=11.0,
            )
        )
    )
    save(plot, "docs/src/examples/out_subtitle_axis_title_styling.svg")