Themes

Theming in fundcloud.plots is a thin alias layer over Plotly's builtin templates. There is no custom theme object — if Plotly already ships the mechanism, fundcloud uses it directly.

Alias map

fundcloud alias	plotly template
default	(no template applied)
white	plotly_white
dark	plotly_dark
ggplot2	ggplot2
seaborn	seaborn

import fundcloud as fc

fc.set_theme("dark")                    # global default for subsequent figures
fc.plots.cumulative(returns).show()

# Per-figure override wins:
fc.plots.cumulative(returns, theme="white").show()

set_theme is re-exported at the top level (same object as fundcloud.plots.set_theme) so the common import fundcloud as fc idiom stays terse. Call fc.get_theme() to read the active alias (default: "default").

Using any registered Plotly template

set_theme accepts any name in plotly.io.templates, so user-defined templates work without a fundcloud-specific API:

import plotly.io as pio
import plotly.graph_objects as go

# Your brand template
pio.templates["my-brand"] = go.layout.Template(
    layout={
        "colorway": ["#003a70", "#e6a817", "#6ab04c"],
        "paper_bgcolor": "#fafafa",
        "font": {"family": "Söhne, system-ui"},
    }
)

fc.set_theme("my-brand")
fc.plots.summary(returns).write_html("branded.html")

An unknown name raises ValueError listing every template available in the current process.

HTML / PDF tear sheets pick up the active theme

Tearsheet.render_html builds its Plotly figures through these same builders — so switching theme before calling render_html rethemes the report:

import fundcloud as fc
from fundcloud.reports import Tearsheet

fc.set_theme("dark")
Tearsheet(portfolio).render_html("dark.html")

render_pdf (matplotlib) is not theme-aware; matplotlib theming is not supported today and is explicitly out of scope.

Why Plotly-only?

Fundcloud is plotly-first; matplotlib exists because WeasyPrint and PdfPages need it. Adding a second theme system would double the surface area for a secondary output path. If dark-mode PDFs become important later we'll add an mpl_rc alias map with the same five names — same alias, different backend.