# Theme Lab: Tune Family, Preset, and Rhythm

## What Is This Page For?

Use this page to choose a visual direction before you retrofit or create vignettes. You can tune one parameter at a time and immediately see the effect on hierarchy, contrast, and page rhythm.

Start with family and preset, then tune style, then adjust content width. That order gives the fastest path to a coherent page.

## How Do You Use It?

1. Pick a family for color character (the four chips show its tones).
2. Pick a direction: warm homage or cool interaction.
3. Toggle style intensity to set structural emphasis (marker + rule weight).
4. Adjust content width to match prose density.

Family
Direction
Style
Content width (ch)
A900 A700 A500 A300

family=red | preset=homage | style=minimal | width=80ch

## What Does Each Control Change?

- `family`: accent hue and contrast character for links, rules, the nested-square marker, and plot palettes (the four chips above show the active family’s tones).
- `preset` (direction): warm homage (cream ground, serif body, light code) vs cool interaction (grey ground, grotesk, dark code).
- `style`: structural weight (`minimal`, `balanced`, `assertive`).
- `content_width`: reading measure in `ch` units.

## Can You Validate The Palette Quickly?

    pal <- albersdown::albers_palette(params$family)
    stopifnot(
      identical(names(pal), c("A900", "A700", "A500", "A300")),
      all(nzchar(unname(pal)))
    )
    knitr::kable(data.frame(tone = names(pal), hex = unname(pal)), format = "html")

tone | hex
--- | ---
A900 | #C22B23
A700 | #DC3925
A500 | #E44926
A300 | #E35B2D

## Copy Into YAML

    params:
      family: red
      preset: homage
      base_size: 13
      content_width: 80
      style: minimal

## Example Plot

    mtcars$grp <- factor(mtcars$cyl)
    stopifnot(length(levels(mtcars$grp)) >= 3)

    ggplot(mtcars, aes(wt, mpg, colour = grp)) +
      geom_point(size = 2.2) +
      labs(
        title = "Theme Lab preview",
        subtitle = "Tune family + preset + style, then copy YAML"
      )