Sirocco keeps its theme.yaml config_schema to five options. Here's what
each one does, and what this demo site actually has set — you're reading
the result of these values right now, not a description of them.
color_scheme
Eight curated presets — blue, slate, green, purple, amber, rose, terracotta, teal (UI labels: Cobalt, Emerald, Indigo, Crimson, Terracotta, Teal, etc.) — rather than a freeform color picker. This demo uses the schema default, blue. Each preset drives the accent color (link color, the active nav item's text and underline, blockquote borders, pagination and search-result hovers) plus a tinted card background on post entries, search results, archive/section lists, and table row striping, and subtler tints on the page body and code blocks derived from that same card tint — so switching presets recolors the whole page, not just the links.
scheme_switcher
Off by default — most sites want one consistent brand color, not a menu of
options for visitors. This demo turns it on: the dropdown next to the
dark-mode toggle lets you preview the other five presets without touching
this site's actual configuration (your pick is remembered in
localStorage, same as the light/dark choice).
default_dark
Off in this demo (the schema default). The header's sun/moon toggle still
switches at runtime and remembers your choice in localStorage regardless
of this setting. default_dark only decides which mode a first-time
visitor sees before they've chosen for themselves — and only when it's
turned on; left off, a first-time visitor's own OS light/dark preference
decides instead (including for visitors with JS disabled, via a pure-CSS
fallback), rather than always defaulting to light.
show_reading_time
On in this demo. Every post's meta line — the one under the title, next to the date — includes a "N min" estimate computed from the post's actual word count. Turn it off and that meta line just shows the date and author instead.
home_subtitle
The line under the title on the home page. This demo sets it to introduce what you're looking at, instead of leaving it blank.
None of these require touching a template file — the admin panel's Theme
Settings tab renders a form from this same config_schema, no code
changes needed for any of the above.