\input texinfo    @c -*- texinfo -*-
@c %**start of header
@setfilename ../../info/modus-themes.info
@settitle Modus themes for GNU Emacs
@include docstyle.texi
@documentencoding UTF-8
@documentlanguage en
@c %**end of header

@include emacsver.texi

@dircategory Emacs misc features
@direntry
* Modus Themes: (modus-themes). Highly accessible themes (WCAG AAA).
@end direntry

@finalout
@titlepage
@title Modus themes for GNU Emacs
@author Protesilaos Stavrou (@email{info@@protesilaos.com})
@end titlepage

@ifnottex
@node Top
@top Modus themes for GNU Emacs

This manual, written by Protesilaos Stavrou, describes the customization
options for the @samp{modus-operandi} and @samp{modus-vivendi} themes, and provides
every other piece of information pertinent to them.

The documentation furnished herein corresponds to version 0.13.0,
released on 2020-10-08.  Any reference to a newer feature which does
not yet form part of the latest tagged commit, is explicitly marked as
such.

Copyright (C) 2020 Free Software Foundation, Inc.

@quotation
Permission is granted to copy, distribute and/or modify this
document under the terms of the GNU Free Documentation License,
Version 1.3 or any later version published by the Free Software
Foundation; with no Invariant Sections, with no Front-Cover Texts,
and with no Back-Cover Texts.

@end quotation

@end ifnottex

@menu
* Overview::
* Installation::
* Enable and load::
* Customization Options::
* Advanced customization (do-it-yourself)::
* Face coverage::
* Notes for individual packages::
* Contributing::
* Acknowledgements::
* Meta::
* External projects (ports)::
* GNU Free Documentation License::

@detailmenu
--- The Detailed Node Listing ---

Overview

* How do the themes look like::
* Learn about the latest changes::

Installation

* Install from the archives::
* Install on GNU/Linux::

Install on GNU/Linux

* Debian 11 Bullseye::
* GNU Guix::

Enable and load

* Load automatically::
* Load at a given time or at sunset/sunrise::
* Toggle between the themes on demand::
* Configure options prior to loading::

Customization Options

* Bold constructs::              Toggle bold constructs in code
* Slanted constructs::           Toggle slanted constructs (italics) in code
* Syntax highlighting::          Toggle subtle coloration in programming modes
* No mixed fonts::               Toggle mixing of font families
* Link underline::               Toggle underlined text in links
* Command prompts::              Choose among plain, subtle, or intense prompts
* Mode line::                    Choose among plain, three-dimension, or moody-compliant styles
* Completion UIs::               Choose among standard, moderate, or opinionated looks
* Fringes::                      Choose among plain, subtle, or intense fringe visibility
* Line highlighting::            Toggle intense style for current line highlighting
* Matching parentheses::         Toggle intense style for matching delimiters/parentheses
* Diffs::                        Choose among intense, desaturated, or text-only diffs
* Org mode blocks::              Choose among plain, greyscale, or rainbow styles
* Heading styles::               Choose among several styles, also per heading level
* Scaled headings::              Toggle scaling of headings
* Headings' font::               Toggle proportionately spaced fonts in headings

Scaled headings

* Scaled heading sizes::         Specify rate of increase for scaled headings

Advanced customization (do-it-yourself)

* Tweak colors (DIY)::           Declare your own palette overrides
* Font configs (DIY)::           Optimise for mixed typeface buffers
* Org user faces (DIY)::         Extend styles for org-mode keywords and priorities

Face coverage

* Supported packages::           Full list of covered face groups
* Covered indirectly::
* Will NOT be supported::

Notes for individual packages

* Note on company-mode overlay pop-up::
* Note for ERC escaped color sequences::
* Note for powerline or spaceline::
* Note on shr colors::
* Note for Helm grep::
* Note on vc-annotate-background-mode::

Contributing

* Sources of the themes::
* Issues you can help with::
* Merge requests::               Legal considerations for code patches

@end detailmenu
@end menu

@node Overview
@chapter Overview

The Modus themes are designed for accessible readability.  They conform
with the highest standard for color contrast between any given
combination of background and foreground values.  This corresponds to
the WCAG AAA standard, which specifies a minimum rate of distance in
relative luminance of 7:1.

Modus Operandi (@samp{modus-operandi}) is a light theme, while Modus Vivendi
(@samp{modus-vivendi}) is dark.  Each theme's color palette is designed to
meet the needs of the numerous interfaces that are possible in the Emacs
computing environment.

The overarching objective of this project is to always offer accessible
color combinations.  There shall never be a compromise on this
principle.  If there arises an inescapable trade-off between readability
and stylistic considerations, we will always opt for the former.

To ensure that users have a consistently accessible experience, the
themes strive to achieve as close to full face coverage as possible
(see @ref{Face coverage}).

Starting with version 0.12.0 and onwards, the themes are built into GNU
Emacs (current version is 0.13.0).

@menu
* How do the themes look like::
* Learn about the latest changes::
@end menu

@node How do the themes look like
@section How do the themes look like

Check the web page with @uref{https://protesilaos.com/modus-themes-pictures/, the screen shots}.  There are lots of scenarios on
display that draw attention to details and important aspects in the
design of the themes.  They also showcase the numerous customization
options.

@xref{Customization Options}.

@node Learn about the latest changes
@section Learn about the latest changes

Please refer to the @uref{https://protesilaos.com/modus-themes-changelog, web page with the change log}.  It is comprehensive
and covers everything that goes into every tagged release of the themes.

@node Installation
@chapter Installation

The Modus themes are distributed with Emacs starting with version 28.1.
On older versions of Emacs, they can be installed using Emacs' package
manager or manually from their code repository.

Modus Operandi (light theme) and Modus Vivendi (dark) are normally
distributed as standalone packages in Emacs-specific archives.  There
also exist packages for GNU/Linux distributions.

@menu
* Install from the archives::
* Install on GNU/Linux::
@end menu

@node Install from the archives
@section Install from the archives

@samp{modus-operandi-theme} and @samp{modus-vivendi-theme} are
available from the GNU ELPA archive, which is configured by default.

Prior to querying any package archive, make sure to have updated the
index, with @samp{M-x package-refresh-contents}.  Then all you need to do is
type @samp{M-x package-install} and specify the theme of your choice.

@node Install on GNU/Linux
@section Install on GNU/Linux

The themes are also available from the archives of some GNU/Linux
distributions.  These should correspond to a tagged release rather than
building directly from the latest Git commit.  It all depends on the
distro's packaging policies.

@menu
* Debian 11 Bullseye::
* GNU Guix::
@end menu

@node Debian 11 Bullseye
@subsection Debian 11 Bullseye

The two themes are distributed as a single package for Debian and its
derivatives.  Currently in the unstable and testing suites and should be
available in time for Debian 11 Bullseye (next stable).

Get them with:

@example
sudo apt install elpa-modus-themes
@end example

@node GNU Guix
@subsection GNU Guix

Users of either the Guix System (the distro) or just Guix (the package
manager) can get each theme as a standalone package.

@example
guix package -i emacs-modus-operandi-theme
@end example

And/or:

@example
guix package -i emacs-modus-vivendi-theme
@end example

@node Enable and load
@chapter Enable and load

This section documents how to load the theme of your choice and how to
further control its initialization.  It also includes some sample code
snippets that could help you in the task, especially if you intend to
use both Modus Operandi and Modus Vivendi.

@menu
* Load automatically::
* Load at a given time or at sunset/sunrise::
* Toggle between the themes on demand::
* Configure options prior to loading::
@end menu

@node Load automatically
@section Load automatically

A simple way to load the theme from your Emacs initialization file is to
include either of the following expressions:

@lisp
(load-theme 'modus-operandi t)          ; Light theme
(load-theme 'modus-vivendi t)           ; Dark theme
@end lisp

Make sure to remove any other theme that is being loaded, otherwise you
might run into unexpected issues.

Note that you can always @samp{M-x disable-theme} and specify an item.  The
command does exactly what its name suggests.  To deactivate all enabled
themes at once, in case you have multiple of them enabled, you may
evaluate the expression:

@lisp
(mapc #'disable-theme custom-enabled-themes)
@end lisp

@node Load at a given time or at sunset/sunrise
@section Load at a given time or at sunset/sunrise

It is possible to schedule a time during the day at or after which a
given theme will be loaded.@footnote{Contributed on Reddit by user @samp{b3n}
@uref{https://www.reddit.com/r/emacs/comments/gdtqov/weekly_tipstricketc_thread/fq9186h/}.}

@lisp
;; Light for the day
(load-theme 'modus-operandi t t)
(run-at-time "05:00" (* 60 60 24)
             (lambda ()
               (enable-theme 'modus-operandi)))

;; Dark for the night
(load-theme 'modus-vivendi t t)
(run-at-time "21:00" (* 60 60 24)
             (lambda ()
               (enable-theme 'modus-vivendi)))
@end lisp

A modified version of the above technique is to use the sunrise and
sunset as references, instead of specifying a fixed hour value.@footnote{Contributed directly by André Alexandre Gomes @uref{https://gitlab.com/aadcg}.}
If you set @samp{calendar-latitude} and @samp{calendar-longitude} (defined in the
built-in @samp{solar.el} library---read it with @samp{M-x find-library}), you can
automatically switch between both themes at the appropriate time-of-day.
Note that @emph{those calendar variables need to be set before loading the
themes}.

@lisp
;; Define coordinates
(setq calendar-latitude 35.17
      calendar-longitude 33.36)

;; Light at sunrise
(load-theme 'modus-operandi t t)
(run-at-time (nth 1 (split-string (sunrise-sunset)))
             (* 60 60 24)
             (lambda ()
               (enable-theme 'modus-operandi)))

;; Dark at sunset
(load-theme 'modus-vivendi t t)
(run-at-time (nth 4 (split-string (sunrise-sunset)))
             (* 60 60 24)
             (lambda ()
               (enable-theme 'modus-vivendi)))
@end lisp

For the sake of completeness, the @samp{load-theme} call in these snippets is
slightly different than the one shown in @ref{Load automatically}, because it
does not enable the theme directly: the subsequent @samp{enable-theme} does
that when needed.

@node Toggle between the themes on demand
@section Toggle between the themes on demand

With both themes available, it is possible to design a simple command to
switch between them on demand.

@lisp
(defun modus-themes-toggle ()
  "Toggle between `modus-operandi' and `modus-vivendi' themes."
  (interactive)
  (if (eq (car custom-enabled-themes) 'modus-operandi)
      (progn
        (disable-theme 'modus-operandi)
        (load-theme 'modus-vivendi t))
    (disable-theme 'modus-vivendi)
    (load-theme 'modus-operandi t)))
@end lisp

You could use @samp{(mapc #'disable-theme custom-enabled-themes)} instead of
disabling a single target, but you get the idea.

@node Configure options prior to loading
@section Configure options prior to loading

If you plan to use both themes and wish to apply styles consistently
(see @ref{Customization Options}), you could define wrapper functions around
the standard @samp{load-theme} command.  These extend the simple function we
presented in @ref{Toggle between the themes on demand}.

Here is a comprehensive setup (the values assigned to the variables are
just for the sake of this demonstration):@footnote{The @samp{defmacro} and @samp{dolist}
method were contributed on Reddit by user @samp{b3n},
@uref{https://www.reddit.com/r/emacs/comments/gqsz8u/weekly_tipstricketc_thread/fsfakhg/}.}

@lisp
(defmacro modus-themes-format-sexp (sexp &rest objects)
  `(eval (read (format ,(format "%S" sexp) ,@@objects))))

(dolist (theme '("operandi" "vivendi"))
  (modus-themes-format-sexp
   (defun modus-%1$s-theme-load ()
     (setq modus-%1$s-theme-slanted-constructs t
           modus-%1$s-theme-bold-constructs t
           modus-%1$s-theme-fringes 'subtle ; @{nil,'subtle,'intense@}
           modus-%1$s-theme-mode-line '3d ; @{nil,'3d,'moody@}
           modus-%1$s-theme-faint-syntax nil
           modus-%1$s-theme-intense-hl-line nil
           modus-%1$s-theme-intense-paren-match nil
           modus-%1$s-theme-no-link-underline t
           modus-%1$s-theme-no-mixed-fonts nil
           modus-%1$s-theme-prompts nil ; @{nil,'subtle,'intense@}
           modus-%1$s-theme-completions 'moderate ; @{nil,'moderate,'opinionated@}
           modus-%1$s-theme-diffs nil ; @{nil,'desaturated,'fg-only@}
           modus-%1$s-theme-org-blocks 'greyscale ; @{nil,'greyscale,'rainbow@}
           modus-%1$s-theme-headings  ; Read further below in the manual for this one
           '((1 . section)
             (2 . line)
             (t . rainbow-line-no-bold))
           modus-%1$s-theme-variable-pitch-headings nil
           modus-%1$s-theme-scale-headings t
           modus-%1$s-theme-scale-1 1.1
           modus-%1$s-theme-scale-2 1.15
           modus-%1$s-theme-scale-3 1.21
           modus-%1$s-theme-scale-4 1.27
           modus-%1$s-theme-scale-5 1.33)
     (load-theme 'modus-%1$s t))
   theme))

(defun modus-themes-toggle ()
  "Toggle between `modus-operandi' and `modus-vivendi' themes."
  (interactive)
  (if (eq (car custom-enabled-themes) 'modus-operandi)
      (progn
        (disable-theme 'modus-operandi)
        (modus-vivendi-theme-load))
    (disable-theme 'modus-vivendi)
    (modus-operandi-theme-load)))
@end lisp

@node Customization Options
@chapter Customization Options

The Modus themes are highly configurable, though they should work well
without any further tweaks.

By default, all customization options are set to @samp{nil}.

All customization options need to be evaluated before loading their
theme (@pxref{Enable and load}).

@menu
* Bold constructs::              Toggle bold constructs in code
* Slanted constructs::           Toggle slanted constructs (italics) in code
* Syntax highlighting::          Toggle subtle coloration in programming modes
* No mixed fonts::               Toggle mixing of font families
* Link underline::               Toggle underlined text in links
* Command prompts::              Choose among plain, subtle, or intense prompts
* Mode line::                    Choose among plain, three-dimension, or moody-compliant styles
* Completion UIs::               Choose among standard, moderate, or opinionated looks
* Fringes::                      Choose among plain, subtle, or intense fringe visibility
* Line highlighting::            Toggle intense style for current line highlighting
* Matching parentheses::         Toggle intense style for matching delimiters/parentheses
* Diffs::                        Choose among intense, desaturated, or text-only diffs
* Org mode blocks::              Choose among plain, greyscale, or rainbow styles
* Heading styles::               Choose among several styles, also per heading level
* Scaled headings::              Toggle scaling of headings
* Headings' font::               Toggle proportionately spaced fonts in headings
@end menu

@node Bold constructs
@section Option for more bold constructs

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-bold-constructs}
@item
@samp{modus-vivendi-theme-bold-constructs}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{t}
@end enumerate

Display several constructs in bold weight.  This concerns keywords and
other important aspects of code syntax.  It also affects certain mode
line indicators and command-line prompts.

The default is to only use a bold weight when it is required.

Additionally, and while not necessary, to define the precise weight for
bold constructs, you can change the typographic intensity of the @samp{bold}
face.  The standard is a bold weight.  It requires no further
intervention.  Assuming though that your typeface of choice supports a
``semibold'' weight, adding the following snippet to your init file should
suffice.

@lisp
(set-face-attribute 'bold nil :weight 'semibold)
@end lisp

Note that if you are switching themes, you need to re-evaluate this
expression after the new theme is loaded.

@node Slanted constructs
@section Option for more slanted constructs

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-slanted-constructs}
@item
@samp{modus-vivendi-theme-slanted-constructs}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{t}
@end enumerate

Choose to render more faces in slanted text (italics).  This typically
affects documentation strings and code comments.

The default is to not use italics unless it is absolutely necessary.

@node Syntax highlighting
@section Option for faint code syntax highlighting

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-faint-syntax}
@item
@samp{modus-vivendi-theme-faint-syntax}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{t}
@end enumerate

Use less saturated colors in programming modes for highlighting code
syntax.  The default is to use saturated colors.

This option essentially affects the font-lock faces, so it may also have
implications in other places that are hard-wired to rely directly on
them instead of specifying their own faces (which could inherit from
font-lock if that is the intent).  The author is aware of @samp{vc-dir} as a
case in point.

@node No mixed fonts
@section Option for no font mixing

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-no-mixed-fonts}
@item
@samp{modus-vivendi-theme-no-mixed-fonts}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{t}
@end enumerate

By default, the themes configure some spacing-sensitive faces, such as
Org tables and code blocks, to always inherit from the @samp{fixed-pitch} face.
This is to ensure that those constructs remain monospaced when users opt
for something like the built-in @kbd{M-x variable-pitch-mode}.  Otherwise the
layout would appear broken.  To disable this behaviour, set the option
to @samp{t}.

Users may prefer to use another package for handling mixed typeface
configurations, rather than letting the theme do it, perhaps because a
purpose-specific package has extra functionality.  Two possible options
are @samp{org-variable-pitch} and @samp{mixed-pitch}.

@node Link underline
@section Option for no link underline

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-no-link-underline}
@item
@samp{modus-vivendi-theme-no-link-underline}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{t}
@end enumerate

Remove the underline effect from links, symbolic links, and buttons.
The default is to apply an underline.

@node Command prompts
@section Option for command prompt styles

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-prompts}
@item
@samp{modus-vivendi-theme-prompts}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{subtle}
@item
@samp{intense}
@end enumerate

The symbols ``subtle'' and ``intense'' will apply a combination of accented
background and foreground to the minibuffer and other REPL prompts (like
@samp{M-x shell} and @samp{M-x eshell}).  The difference between the two is that the
latter has a more pronounced/noticeable effect than the former.

The default does not use any background for such prompts, while relying
exclusively on an accented foreground color.

@node Mode line
@section Option for mode line presentation

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-mode-line}
@item
@samp{modus-vivendi-theme-mode-line}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{3d}
@item
@samp{moody}
@end enumerate

The default value (@samp{nil}) produces a two-dimensional effect both for the
active and inactive modelines.  The differences between the two are
limited to distinct shades of greyscale values, with the active being
more intense than the inactive.

A @samp{3d} symbol will make the active modeline look like a three-dimensional
rectangle.  Inactive modelines remain 2D, though they are slightly toned
down relative to the default.  This aesthetic is the same as what you
get when you run Emacs without any customizations (@kbd{emacs -Q} on the
command line).

While @samp{moody} removes all box effects from the modelines and applies
underline and overline properties instead.  It also tones down a bit the
inactive modelines.  This is meant to optimize things for use with the
@uref{https://github.com/tarsius/moody, moody package} (hereinafter referred to as ``Moody''), though it can work
fine even without it.

Note that Moody does not expose any faces that the themes could style
directly.  Instead it re-purposes existing ones to render its tabs and
ribbons.  As such, there may be cases where the contrast ratio falls
below the 7:1 target that the themes conform with (WCAG AAA).  To hedge
against this, we configure a fallback foreground for the @samp{moody} option,
which will come into effect when the background of the modeline changes
to something less accessible, such as Moody ribbons (read the doc string
of @samp{set-face-attribute}, specifically @samp{:distant-foreground}).  This fallback
comes into effect when Emacs determines that the background and
foreground of the given construct are too close to each other in terms
of color distance.  In effect, users would need to experiment with the
variable @samp{face-near-same-color-threshold} to trigger the fallback color.
We find that a value of @samp{45000} would suffice, contrary to the default
@samp{30000}.  Do not set the value too high, because that would have the
adverse effect of always overriding the default color (which has been
carefully designed to be highly accessible).

Furthermore, because Moody expects an underline and overline instead of
a box style, it is recommended you also include this in your setup:

@lisp
(setq x-underline-at-descent-line t)
@end lisp

@node Completion UIs
@section Option for completion framework aesthetics

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-completions}
@item
@samp{modus-vivendi-theme-completions}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{moderate}
@item
@samp{opinionated}
@end enumerate

This is a special option that has different effects depending on the
completion UI@.  The interfaces can be grouped in two categories, based
on their default aesthetics: (i) those that only or mostly use
foreground colors for their interaction model, and (ii) those that
combine background and foreground values for some of their metaphors.
The former category encompasses Icomplete, Ido, Selectrum as well as
pattern matching styles like Orderless and Flx.  The latter covers Helm,
Ivy, and similar.

A value of @samp{nil} will respect the metaphors of each completion framework.

The symbol @samp{moderate} will apply a combination of background and
foreground that is fairly subtle.  For Icomplete and friends this
constitutes a departure from their default aesthetics, however the
difference is small.  While Helm et al will appear slightly different
than their original looks, as they are toned down a bit.

The symbol @samp{opinionated} will apply color combinations that refashion the
completion UI@.  For the Icomplete camp this means that intense
background and foreground combinations are used: in effect their looks
emulate those of Ivy and co. in their original style.  Whereas the other
group of packages will revert to an even more nuanced aesthetic with
some additional changes to the choice of hues.

To appreciate the scope of this customization option, you should spend
some time with every one of the @samp{nil} (default), @samp{moderate}, and @samp{opinionated}
possibilities.

@node Fringes
@section Option for fringe visibility

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-fringes}
@item
@samp{modus-vivendi-theme-fringes}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{subtle}
@item
@samp{intense}
@end enumerate

The ``subtle'' symbol will apply a greyscale background that is visible,
yet close enough to the main background color.  While the ``intense''
symbol will use a more noticeable greyscale background.

The default is to use the same color as that of the main background,
meaning that the fringes are not obvious though they still occupy the
space given to them by @samp{fringe-mode}.

@node Line highlighting
@section Option for line highlighting (hl-line-mode)

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-intense-hl-line}
@item
@samp{modus-vivendi-theme-intense-hl-line}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{t}
@end enumerate

Draw the current line of @samp{hl-line-mode} or its global equivalent in a more
prominent background color.  This would also affect several packages
that enable @samp{hl-line-mode}, such as @samp{elfeed} and @samp{mu4e}.

The default is to use a more subtle gray.

@node Matching parentheses
@section Option for parenthesis matching (show-paren-mode)

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-intense-paren-match}
@item
@samp{modus-vivendi-theme-intense-paren-match}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{t}
@end enumerate

Apply a more intense background to the matching parentheses (or
delimiters).  This affects tools such as the built-in @samp{show-paren-mode}.
The default is to use a subtle warm color for the background of those
overlays.

@node Diffs
@section Option for diff buffer looks

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-diffs}
@item
@samp{modus-vivendi-theme-diffs}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{desaturated}
@item
@samp{fg-only}
@end enumerate

By default the themes will apply richly colored backgrounds to the
output of diffs, such as those of @samp{diff-mode}, @samp{ediff}, @samp{smerge-mode}, and
@samp{magit}.  These are color combinations of an accented background and
foreground so that, for example, added lines have a pronounced green
background with an appropriate shade of green for the affected text.
Word-wise or ``refined'' changes follow this pattern but use different
shades of those colors to remain distinct.

A @samp{desaturated} value tones down all relevant color values.  It still
combines an accented background with an appropriate foreground, yet its
overall impression is very subtle.  Refined changes are a bit more
intense to fulfil their intended function, though still less saturated
than default.

While @samp{fg-only} will remove all accented backgrounds and instead rely on
color-coded text to denote changes.  For instance, added lines use an
intense green foreground, while their background is the same as the rest
of the buffer.  Word-wise highlights still use a background value which
is, nonetheless, more subtle than its default equivalent.

Concerning @samp{magit}, an extra set of tweaks are introduced for the effect
of highlighting the current diff hunk, so as to remain consistent with
the overall experience of that mode.  Expect changes that are consistent
with the overall intent of the aforementioned.

@node Org mode blocks
@section Option for org-mode block styles

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-org-blocks}
@item
@samp{modus-vivendi-theme-org-blocks}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{greyscale}
@item
@samp{rainbow}
@end enumerate

The default is to use the same background as the rest of the buffer for
the contents of the block.

A value of @samp{greyscale} will apply a subtle neutral gray background to the
block's contents.  It will also extend to the edge of the window the
background of the ``begin'' and ``end'' block delimiter lines (only relevant
for Emacs versions >= 27 where the 'extend' keyword is recognised by
@samp{set-face-attribute}).

While @samp{rainbow} will instead use an accented background for the contents
of the block.  The exact color will depend on the programming language
and is controlled by the @samp{org-src-block-faces} variable (refer to the
theme's source code for the current association list).  This is most
suitable for users who work on literate programming documents that mix
and match several languages.

Note that the ``rainbow'' blocks may require you to also reload the
major-mode so that the colors are applied properly: use @kbd{M-x org-mode} or
@kbd{M-x org-mode-restart} to refresh the buffer.  Or start typing in each
code block (inefficient at scale, but it still works).

@node Heading styles
@section Option for headings' overall style

This is defined as an alist and, therefore, uses a different approach
than other customization options documented in this manual.

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-headings}
@item
@samp{modus-vivendi-theme-headings}
@end itemize

Possible values, which can be specified for each heading level (examples
further below):

@itemize
@item
nil (default fallback option---covers all heading levels)
@item
@samp{t} (default style for a single heading, when the fallback differs)
@item
@samp{no-bold}
@item
@samp{line}
@item
@samp{line-no-bold}
@item
@samp{rainbow}
@item
@samp{rainbow-line}
@item
@samp{rainbow-line-no-bold}
@item
@samp{highlight}
@item
@samp{highlight-no-bold}
@item
@samp{rainbow-highlight}
@item
@samp{rainbow-highlight-no-bold}
@item
@samp{section}
@item
@samp{section-no-bold}
@item
@samp{rainbow-section}
@item
@samp{rainbow-section-no-bold}
@end itemize

To control faces per level from 1-8, use something like this (same for
@samp{modus-vivendi-theme-headings}):

@lisp
(setq modus-operandi-theme-headings
      '((1 . section)
        (2 . line)
        (3 . highlight)
        (t . rainbow-no-bold)))
@end lisp

The above uses the @samp{section} value for heading levels 1, the @samp{line} for
headings 2, @samp{highlight} for 3.  All other levels fall back to
@samp{rainbow-line-no-bold}.

To set a uniform value for all heading levels, use this pattern:

@lisp
;; A given style for every heading
(setq modus-operandi-theme-headings
      '((t . rainbow-line-no-bold)))

;; Default aesthetic for every heading
(setq modus-operandi-theme-headings
      '((t . nil)))
@end lisp

The default style for headings uses a fairly desaturated foreground
value in combination with a bold typographic weight.  To specify this
style for a given level N (assuming you wish to have another fallback
option), just specify the value @samp{t} like this:

@lisp
(setq modus-operandi-theme-headings
      '((1 . t)
        (2 . line)
        (t . rainbow-line-no-bold)))
@end lisp

A description of all other possible styles:

@itemize
@item
@samp{no-bold} retains the default text color while removing the typographic
weight.

@item
@samp{line} is the same as the default plus an overline over the heading.

@item
@samp{line-no-bold} is the same as @samp{line} without bold weight.

@item
@samp{rainbow} uses a more colorful foreground in combination with bold
weight.

@item
@samp{rainbow-line} is the same as @samp{rainbow} plus an overline.

@item
@samp{rainbow-line-no-bold} is the same as @samp{rainbow-line} without the bold
weight.

@item
@samp{highlight} retains the default style of a fairly desaturated foreground
combined with a bold weight and adds to it a subtle accented
background.

@item
@samp{highlight-no-bold} is the same as @samp{highlight} without a bold weight.

@item
@samp{rainbow-highlight} is the same as @samp{highlight} but with a more colorful
foreground.

@item
@samp{rainbow-highlight-no-bold} is the same as @samp{rainbow-highlight} without a
bold weight.

@item
@samp{section} retains the default looks and adds to them both an overline
and a slightly accented background.  It is, in effect, a combination
of the @samp{line} and @samp{highlight} values.

@item
@samp{section-no-bold} is the same as @samp{section} without a bold weight.

@item
@samp{rainbow-section} is the same as @samp{section} but with a more colorful
foreground.

@item
@samp{rainbow-section-no-bold} is the same as @samp{rainbow-section} without a bold
weight.``
@end itemize

@node Scaled headings
@section Option for scaled headings

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-scale-headings}
@item
@samp{modus-vivendi-theme-scale-headings}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{t}
@end enumerate

Make headings larger in height relative to the main text.  This is
noticeable in modes like Org.  The default is to use the same size for
headings and body copy.

@menu
* Scaled heading sizes::         Specify rate of increase for scaled headings
@end menu

@node Scaled heading sizes
@subsection Control the scale of headings

In addition to toggles for enabling scaled headings, users can also
specify a number of their own.

@itemize
@item
If it is a floating point, say, @samp{1.5}, it is interpreted as a multiple
of the base font size.  This is the recommended method.

@item
If it is an integer, it is read as an absolute font height.  The
number is basically the point size multiplied by ten.  So if you want
it to be @samp{18pt} you must pass @samp{180}.  Please understand that setting an
absolute value is discouraged, as it will break the layout when you
try to change font sizes with the built-in @samp{text-scale-adjust} command
(see @ref{Font configs (DIY), , Font configurations}).
@end itemize

Below are the variables in their default values, using the floating
point paradigm.  The numbers are very conservative, but you are free to
change them to your liking, such as @samp{1.2}, @samp{1.4}, @samp{1.6}, @samp{1.8}, @samp{2.0}---or use a
resource for finding a consistent scale:

@lisp
(setq modus-operandi-theme-scale-1 1.05
      modus-operandi-theme-scale-2 1.1
      modus-operandi-theme-scale-3 1.15
      modus-operandi-theme-scale-4 1.2
      modus-operandi-theme-scale-5 1.3)

(setq modus-vivendi-theme-scale-1 1.05
      modus-vivendi-theme-scale-2 1.1
      modus-vivendi-theme-scale-3 1.15
      modus-vivendi-theme-scale-4 1.2
      modus-vivendi-theme-scale-5 1.3)
@end lisp

Note that in earlier versions of Org, scaling would only increase the
size of the heading, but not of keywords that were added to it, like
``TODO''.  The issue has been fixed upstream:
@uref{https://protesilaos.com/codelog/2020-09-24-org-headings-adapt/}.

@node Headings' font
@section Option for variable-pitch font in headings

Symbol names:

@itemize
@item
@samp{modus-operandi-theme-variable-pitch-headings}
@item
@samp{modus-vivendi-theme-variable-pitch-headings}
@end itemize

Possible values:

@enumerate
@item
@samp{nil} (default)
@item
@samp{t}
@end enumerate

Choose to apply a proportionately spaced, else ``variable-pitch'',
typeface to headings (such as in Org mode).  The default is to use the
main font family.

@ref{Font configs (DIY), , Font configurations for Org (and others)}.

@node Advanced customization (do-it-yourself)
@chapter Advanced customization (do-it-yourself)

Unlike the predefined customization options which follow a
straightforward pattern of allowing the user to quickly specify their
preference, the themes also provide a more flexible, albeit difficult,
mechanism to control things with precision (see @ref{Customization Options}).

This section is of interest only to users who are prepared to maintain
their own local tweaks and who are willing to deal with any possible
incompatibilities between versioned releases of the themes.  As such,
they are labelled as ``do-it-yourself'' or ``DIY''.

@menu
* Tweak colors (DIY)::           Declare your own palette overrides
* Font configs (DIY)::           Optimise for mixed typeface buffers
* Org user faces (DIY)::         Extend styles for org-mode keywords and priorities
@end menu

@node Tweak colors (DIY)
@section Full access to the themes' palette

The variables are:

@itemize
@item
@samp{modus-operandi-theme-override-colors-alist}
@item
@samp{modus-vivendi-theme-override-colors-alist}
@end itemize

Users can specify an association list that maps the names of color
variables to hexadecimal RGB values (in the form of @samp{#RRGGBB}).  This
means that it is possible to override the entire palette or subsets
thereof (see the source code for the actual names and values).

Example:

@lisp
;; Redefine the values of those three variables for the given theme
(setq modus-vivendi-theme-override-colors-alist
      '(("magenta" . "#ffaabb")
        ("magenta-alt" . "#ee88ff")
        ("magenta-alt-other" . "#bbaaff")))
@end lisp

If you want to be creative, you can define a minor mode that refashions
the themes on demand.  The following is a minor mode that gets activated
on demand.  We combine it with the function to switch between Modus
Operandi and Modus Vivendi (@pxref{Toggle between the themes on demand}, for
a basic command, and/or @pxref{Configure options prior to loading}, for a more
comprehensive setup).

@lisp
(define-minor-mode modus-themes-alt-mode
  "Override Modus themes' palette variables with custom values.

This is intended as a proof-of-concept.  It is, nonetheless, a
perfectly accessible alternative, conforming with the design
principles of the Modus themes.  It still is not as good as the
default colors."
  :init-value nil
  :global t
  (if modus-themes-alt-mode
      (setq modus-operandi-theme-override-colors-alist
            '(("bg-main" . "#fefcf4")
              ("bg-dim" . "#faf6ef")
              ("bg-alt" . "#f7efe5")
              ("bg-hl-line" . "#f4f0e3")
              ("bg-active" . "#e8dfd1")
              ("bg-inactive" . "#f6ece5")
              ("bg-region" . "#c6bab1")
              ("bg-header" . "#ede3e0")
              ("bg-tab-bar" . "#dcd3d3")
              ("bg-tab-active" . "#fdf6eb")
              ("bg-tab-inactive" . "#c8bab8")
              ("fg-unfocused" . "#55556f"))
            modus-vivendi-theme-override-colors-alist
            '(("bg-main" . "#100b17")
              ("bg-dim" . "#161129")
              ("bg-alt" . "#181732")
              ("bg-hl-line" . "#191628")
              ("bg-active" . "#282e46")
              ("bg-inactive" . "#1a1e39")
              ("bg-region" . "#393a53")
              ("bg-header" . "#202037")
              ("bg-tab-bar" . "#262b41")
              ("bg-tab-active" . "#120f18")
              ("bg-tab-inactive" . "#3a3a5a")
              ("fg-unfocused" . "#9a9aab")))
    (setq modus-operandi-theme-override-colors-alist nil
          modus-vivendi-theme-override-colors-alist nil)))

(defun modus-themes-toggle (&optional arg)
  "Toggle between `modus-operandi' and `modus-vivendi' themes.

With optional \\[universal-argument] prefix, enable
`modus-themes-alt-mode' for the loaded theme."
  (interactive "P")
  (if arg
      (modus-themes-alt-mode 1)
    (modus-themes-alt-mode -1))
  (if (eq (car custom-enabled-themes) 'modus-operandi)
      (progn
        (disable-theme 'modus-operandi)
        (load-theme 'modus-vivendi t))
    (disable-theme 'modus-vivendi)
    (load-theme 'modus-operandi t)))
@end lisp

@printindex cp

@node Font configs (DIY)
@section Font configurations for Org (and others)

The themes are designed to cope well with mixed font settings (@ref{No mixed fonts, , Option
for no font mixing}).  Currently this applies to @samp{org-mode} and
@samp{markdown-mode}.

In practice it means that the user can safely opt for a more
prose-friendly proportionately spaced typeface as their default, while
letting spacing-sensitive elements like tables and inline code always
use a monospaced font, by inheriting from the @samp{fixed-pitch} face.

Users can try the built-in @kbd{M-x variable-pitch-mode} to see the effect in
action.

To make everything use your desired font families, you need to configure
the @samp{variable-pitch} (proportional spacing) and @samp{fixed-pitch} (monospaced)
faces respectively.  It may also be convenient to set your main typeface
by configuring the @samp{default} face the same way.

Put something like this in your initialization file (make sure to read
the documentation of @samp{set-face-attribute}, with @kbd{M-x describe-function}):

@lisp
;; Main typeface
(set-face-attribute 'default nil :family "DejaVu Sans Mono" :height 110)

;; Proportionately spaced typeface
(set-face-attribute 'variable-pitch nil :family "DejaVu Serif" :height 1.0)

;; Monospaced typeface
(set-face-attribute 'fixed-pitch nil :family "DejaVu Sans Mono" :height 1.0)
@end lisp

Note the differences in the @samp{:height} property.  The @samp{default} face must
specify an absolute value, which is the point size × 10.  So if you want
to use a font at point size @samp{11}, you set the height at @samp{110}.@footnote{@samp{:height}
values do not need to be rounded to multiples of ten: the likes of @samp{115}
are perfectly valid—some typefaces will change to account for those
finer increments.}  Whereas every other face must have a value that is
relative to the default, represented as a floating point (if you use an
integer, say, @samp{15} then that means an absolute height).  This is of
paramount importantance: it ensures that all fonts can scale gracefully
when using something like the @samp{text-scale-adjust} command which only
operates on the base font size (i.e. the @samp{default} face's absolute
height).

An alternative syntax for the @samp{default} face, is to pass all typeface
parameters directly to a @samp{font} property.@footnote{Has the benefit of
accepting @samp{fontconfig} parameters (GNU/Linux), such as @samp{"DejaVu Sans
Mono-11:hintstyle=hintslight:autohint=false"}.
@uref{https://www.freedesktop.org/software/fontconfig/fontconfig-user.html}}
Note that here we use a standard point size:

@lisp
(set-face-attribute 'default nil :font "DejaVu Sans Mono-11")
@end lisp

Again, remember to only ever specify an absolute height for the @samp{default}.

@printindex cp

@node Org user faces (DIY)
@section Org user faces (DIY)

Users of @samp{org-mode} have the option to configure various keywords and
priority cookies to better match their workflow.  User options are
@samp{org-todo-keyword-faces} and @samp{org-priority-faces}.

As those are meant to be custom faces, it would be futile to have the
themes try to guess what each user would want to use, which keywords to
target, and so on.  Instead, we can provide guidelines on how to
customize things to one's liking with the intent of retaining the
overall aesthetics of the theme.

Please bear in mind that the end result of those is not controlled by
the active theme but by how Org maps faces to its constructs.  Editing
those while @samp{org-mode} is active requires @kbd{M-x org-mode-restart} for changes
to take effect.

Let us assume you wish to visually differentiate your keywords.  You
have something like this:

@lisp
(setq org-todo-keywords
      '((sequence "TODO(t)" "|" "DONE(D)" "CANCEL(C)")
        (sequence "MEET(m)" "|" "MET(M)")
        (sequence "STUDY(s)" "|" "STUDIED(S)")
        (sequence "WRITE(w)" "|" "WROTE(W)")))
@end lisp

You could then use a variant of the following to inherit from a face
that uses the styles you want and also to preserve the properties
applied by the @samp{org-todo} face:

@lisp
(setq org-todo-keyword-faces
      '(("MEET" . '(font-lock-preprocessor-face org-todo))
        ("STUDY" . '(font-lock-variable-name-face org-todo))
        ("WRITE" . '(font-lock-type-face org-todo))))
@end lisp

This will refashion the keywords you specify, while letting the other
items in @samp{org-todo-keywords} use their original styles (which are defined
in the @samp{org-todo} and @samp{org-done} faces).

If you want back the defaults, try specifying just the @samp{org-todo} face:

@lisp
(setq org-todo-keyword-faces
      '(("MEET" . org-todo)
        ("STUDY" . org-todo)
        ("WRITE" . org-todo)))
@end lisp

When you inherit from multiple faces, you need to quote the list as
shown further above.  The order is important: the last item is applied
over the previous ones.  If you do not want to blend multiple faces, you
do not need a quoted list.  A pattern of @samp{keyword . face} would suffice.

Both approaches can be used simultaneously, as illustrated in this
configuration of the priority cookies:

@lisp
(setq org-priority-faces
      '((?A . '(org-scheduled-today org-priority))
        (?B . org-priority)
        (?C . '(shadow org-priority))))
@end lisp

To find all the faces that are loaded in your current Emacs session, use
@kbd{M-x list-faces-display}.  Also try @kbd{M-x describe-variable} and then specify
the name of each of those Org variables demonstrated above.  Their
documentation strings will offer you further guidance.

Furthermore, consider reading the ``Notes for aspiring Emacs theme
developers'', published on 2020-08-28 by me (Protesilaos Stavrou):
@uref{https://protesilaos.com/codelog/2020-08-28-notes-emacs-theme-devs/}.

@printindex cp

@printindex cp

@node Face coverage
@chapter Face coverage

Modus Operandi and Modus Vivendi try to provide as close to full face
coverage as possible.  This is necessary to ensure a consistently
accessible reading experience across all possible interfaces.

@menu
* Supported packages::           Full list of covered face groups
* Covered indirectly::
* Will NOT be supported::
@end menu

@node Supported packages
@section Full support for packages or face groups

This list will always be updated to reflect the current state of the
project.  The idea is to offer an overview of the known status of all
affected face groups.  The items with an appended asterisk @samp{*} tend to
have lots of extensions, so the ``full support'' may not be 100% true…

@itemize
@item
ace-window
@item
ag
@item
alert
@item
all-the-icons
@item
annotate
@item
anzu
@item
apropos
@item
apt-sources-list
@item
artbollocks-mode
@item
auctex and @TeX{}
@item
auto-dim-other-buffers
@item
avy
@item
awesome-tray
@item
binder
@item
bm
@item
bongo
@item
boon
@item
breakpoint (provided by the built-in @samp{gdb-mi.el} library)
@item
buffer-expose
@item
calendar and diary
@item
calfw
@item
centaur-tabs
@item
change-log and log-view (such as @samp{vc-print-log} and @samp{vc-print-root-log})
@item
cider
@item
circe
@item
color-rg
@item
column-enforce-mode
@item
company-mode*
@item
company-posframe
@item
compilation-mode
@item
completions
@item
counsel*
@item
counsel-css
@item
counsel-notmuch
@item
counsel-org-capture-string
@item
cov
@item
cperl-mode
@item
csv-mode
@item
ctrlf
@item
custom (@kbd{M-x customize})
@item
dap-mode
@item
dashboard (emacs-dashboard)
@item
deadgrep
@item
debbugs
@item
define-word
@item
deft
@item
dictionary
@item
diff-hl
@item
diff-mode
@item
dim-autoload
@item
dir-treeview
@item
dired
@item
dired-async
@item
dired-git
@item
dired-git-info
@item
dired-narrow
@item
dired-subtree
@item
diredfl
@item
disk-usage
@item
doom-modeline
@item
dynamic-ruler
@item
easy-jekyll
@item
easy-kill
@item
ebdb
@item
ediff
@item
eglot
@item
el-search
@item
eldoc-box
@item
elfeed
@item
elfeed-score
@item
emms
@item
enhanced-ruby-mode
@item
epa
@item
equake
@item
erc
@item
eros
@item
ert
@item
eshell
@item
eshell-fringe-status
@item
eshell-git-prompt
@item
eshell-prompt-extras (epe)
@item
eshell-syntax-highlighting
@item
evil* (evil-mode)
@item
evil-goggles
@item
evil-visual-mark-mode
@item
eww
@item
eyebrowse
@item
fancy-dabbrev
@item
flycheck
@item
flycheck-color-mode-line
@item
flycheck-indicator
@item
flycheck-posframe
@item
flymake
@item
flyspell
@item
flyspell-correct
@item
flx
@item
freeze-it
@item
frog-menu
@item
focus
@item
fold-this
@item
font-lock (generic syntax highlighting)
@item
forge
@item
fountain (fountain-mode)
@item
geiser
@item
git-commit
@item
git-gutter (and variants)
@item
git-lens
@item
git-rebase
@item
git-timemachine
@item
git-walktree
@item
gnus
@item
golden-ratio-scroll-screen
@item
helm*
@item
helm-ls-git
@item
helm-switch-shell
@item
helm-xref
@item
helpful
@item
highlight-blocks
@item
highlight-defined
@item
highlight-escape-sequences (@samp{hes-mode})
@item
highlight-indentation
@item
highlight-numbers
@item
highlight-symbol
@item
highlight-tail
@item
highlight-thing
@item
hl-defined
@item
hl-fill-column
@item
hl-line-mode
@item
hl-todo
@item
hydra
@item
hyperlist
@item
ibuffer
@item
icomplete
@item
icomplete-vertical
@item
ido-mode
@item
iedit
@item
iflipb
@item
imenu-list
@item
indium
@item
info
@item
info-colors
@item
interaction-log
@item
ioccur
@item
isearch, occur, etc.
@item
ivy*
@item
ivy-posframe
@item
jira (org-jira)
@item
journalctl-mode
@item
js2-mode
@item
julia
@item
jupyter
@item
kaocha-runner
@item
keycast
@item
line numbers (@samp{display-line-numbers-mode} and global variant)
@item
lsp-mode
@item
lsp-ui
@item
magit
@item
magit-imerge
@item
man
@item
markdown-mode
@item
markup-faces (@samp{adoc-mode})
@item
mentor
@item
messages
@item
minibuffer-line
@item
minimap
@item
modeline
@item
mood-line
@item
moody
@item
mpdel
@item
mu4e
@item
mu4e-conversation
@item
multiple-cursors
@item
neotree
@item
no-emoji
@item
notmuch
@item
num3-mode
@item
nxml-mode
@item
objed
@item
orderless
@item
org*
@item
org-journal
@item
org-noter
@item
org-pomodoro
@item
org-recur
@item
org-roam
@item
org-superstar
@item
org-table-sticky-header
@item
org-treescope
@item
origami
@item
outline-mode
@item
outline-minor-faces
@item
package (@kbd{M-x list-packages})
@item
page-break-lines
@item
paradox
@item
paren-face
@item
parrot
@item
pass
@item
persp-mode
@item
perspective
@item
phi-grep
@item
phi-search
@item
pkgbuild-mode
@item
pomidor
@item
powerline
@item
powerline-evil
@item
proced
@item
prodigy
@item
racket-mode
@item
rainbow-blocks
@item
rainbow-identifiers
@item
rainbow-delimiters
@item
rcirc
@item
regexp-builder (also known as @samp{re-builder})
@item
rg (rg.el)
@item
ripgrep
@item
rmail
@item
ruler-mode
@item
sallet
@item
selectrum
@item
semantic
@item
sesman
@item
shell-script-mode
@item
show-paren-mode
@item
side-notes
@item
skewer-mode
@item
smart-mode-line
@item
smartparens
@item
smerge
@item
spaceline
@item
speedbar
@item
spell-fu
@item
stripes
@item
suggest
@item
switch-window
@item
swiper
@item
swoop
@item
sx
@item
symbol-overlay
@item
syslog-mode
@item
table (built-in table.el)
@item
telephone-line
@item
term
@item
tomatinho
@item
transient (pop-up windows such as Magit's)
@item
trashed
@item
treemacs
@item
tty-menu
@item
tuareg
@item
typescript
@item
undo-tree
@item
vc (built-in mode line status for version control)
@item
vc-annotate (@kbd{C-x v g})
@item
vdiff
@item
vimish-fold
@item
visible-mark
@item
visual-regexp
@item
volatile-highlights
@item
vterm
@item
wcheck-mode
@item
web-mode
@item
wgrep
@item
which-function-mode
@item
which-key
@item
whitespace-mode
@item
window-divider-mode
@item
winum
@item
writegood-mode
@item
woman
@item
xah-elisp-mode
@item
xref
@item
xterm-color (and ansi-colors)
@item
yaml-mode
@item
yasnippet
@item
ztree
@end itemize

Plus many other miscellaneous faces that are provided by the upstream
GNU Emacs distribution.

@node Covered indirectly
@section Covered indirectly

These do not require any extra styles because they are configured to
inherit from some basic faces.  Please confirm.

@itemize
@item
edit-indirect
@item
evil-owl
@item
perl-mode
@item
php-mode
@item
rjsx-mode
@item
swift-mode
@end itemize

@node Will NOT be supported
@section Will NOT be supported

I have thus far identified a single package that does fit into the
overarching objective of this project: @uref{https://github.com/hlissner/emacs-solaire-mode, solaire}.  It basically tries to
cast a less intense background on the main file-visiting buffers, so
that secondary elements like sidebars can have the default (pure
white/black) background.

I will only cover this package if it ever supports the inverse effect:
less intense colors (but still accessible) for ancillary interfaces
and the intended styles for the content you are actually working on.

@node Notes for individual packages
@chapter Notes for individual packages

This section covers information that may be of interest to users of
individual packages.

@menu
* Note on company-mode overlay pop-up::
* Note for ERC escaped color sequences::
* Note for powerline or spaceline::
* Note on shr colors::
* Note for Helm grep::
* Note on vc-annotate-background-mode::
@end menu

@node Note on company-mode overlay pop-up
@section Note on company-mode overlay pop-up

By default, the @samp{company-mode} pop-up that lists completion candidates is
drawn using an overlay.  This creates alignment issues every time it is
placed above a piece of text that has a different height than the
default.

The solution recommended by the project's maintainer is to use an
alternative front-end for drawing the pop-up which uses child frames
instead of overlays.@footnote{@uref{https://github.com/company-mode/company-mode/issues/1010}}@footnote{@uref{https://github.com/tumashu/company-posframe/}}

@node Note for ERC escaped color sequences
@section Note for ERC escaped color sequences

The built-in IRC client @samp{erc} has the ability to colorise any text using
escape sequences that start with @samp{^C} (inserted with @samp{C-q C-c}) and are
followed by a number for the foreground and background.@footnote{This page
explains the basics, though it is not specific to Emacs:
@uref{https://www.mirc.com/colors.html}} Possible numbers are 0-15, with the
first entry being the foreground and the second the background,
separated by a comma.  Like this @samp{^C1,6}.  The minimum setup is this:

@lisp
(add-to-list 'erc-modules 'irccontrols)
(setq erc-interpret-controls-p t
      erc-interpret-mirc-color t)
@end lisp

As this allows users to make arbitrary combinations, it is impossible to
guarantee a consistently high contrast ratio.  All we can we do is
provide guidance on the combinations that satisfy the accessibility
standard of the themes:

@table @asis
@item Modus Operandi
Use foreground color 1 for all backgrounds from
2-15.  Like so: @samp{C-q C-c1,N} where @samp{N} is the background.

@item Modus Vivendi
Use foreground color 0 for all backgrounds from
2-13.  Use foreground @samp{1} for backgrounds 14, 15.
@end table

Colors 0 and 1 are white and black respectively.  So combine them
together, if you must.

@node Note for powerline or spaceline
@section Note for powerline or spaceline

Both Powerline and Spaceline package users will likely need to use the
command @samp{powerline-reset} whenever they make changes to their themes
and/or modeline setup.

@node Note on shr colors
@section Note on shr colors

Emacs' HTML rendering mechanism (@samp{shr}) may need explicit configuration to
respect the theme's colors instead of whatever specifications the
webpage provides.  Consult @kbd{C-h v shr-use-colors}.

@node Note for Helm grep
@section Note for Helm grep

There is one face from the Helm package that is meant to highlight the
matches of a grep or grep-like command (@samp{ag} or @samp{ripgrep}).  It is
@samp{helm-grep-match}.  However, this face can only apply when the user does
not pass @samp{--color=always} as a command-line option for their command.

Here is the docstring for that face, which is defined in the
@samp{helm-grep.el} library (view a library with @samp{M-x find-library}).

@quotation
Face used to highlight grep matches.  Have no effect when grep backend
use ``--color=''

@end quotation

The user must either remove @samp{--color} from the flags passed to the grep
function, or explicitly use @samp{--color=never} (or equivalent).  Helm
provides user-facing customization options for controlling the grep
function's parameters, such as @samp{helm-grep-default-command} and
@samp{helm-grep-git-grep-command}.

When @samp{--color=always} is in effect, the grep output will use red text in
bold letter forms to present the matching part in the list of
candidates.  That style still meets the contrast ratio target of >= 7:1
(accessibility standard WCAG AAA), because it draws the reference to
ANSI color number 1 (red) from the already-supported array of
@samp{ansi-color-names-vector}.

@node Note on vc-annotate-background-mode
@section Note on vc-annotate-background-mode

Due to the unique way @samp{vc-annotate} (@kbd{C-x v g}) applies colors, support for
its background mode (@samp{vc-annotate-background-mode}) is disabled at the
theme level.

Normally, such a drastic measure should not belong in a theme: assuming
the user's preferences is bad practice.  However, it has been deemed
necessary in the interest of preserving color contrast accessibility
while still supporting a useful built-in tool.

If there actually is a way to avoid such a course of action, without
prejudice to the accessibility standard of this project, then please
report as much or send patches (see @ref{Contributing}).

@node Contributing
@chapter Contributing

This section documents the canonical sources of the themes and the ways
in which you can contribute to their ongoing development.

@menu
* Sources of the themes::
* Issues you can help with::
* Merge requests::               Legal considerations for code patches
@end menu

@node Sources of the themes
@section Sources of the themes

The @samp{modus-operandi} and @samp{modus-vivendi} themes are built into Emacs.
Currently they are in the project's @samp{master} branch, which is tracking the
next development release target.

The source code of the themes is @uref{https://gitlab.com/protesilaos/modus-themes/, available on Gitlab}, for the time
being.  A @uref{https://github.com/protesilaos/modus-themes/, mirror on Github} is also on offer.

An HTML version of this manual is available as an extension to the
@uref{https://protesilaos.com/modus-themes/, author's personal website} (does not rely on any non-free code).

@node Issues you can help with
@section Issues you can help with

A few tasks you can help with:

@itemize
@item
Suggest refinements to packages that are covered.
@item
Report packages not covered thus far.
@item
Report bugs, inconsistencies, shortcomings.
@item
Help expand the documentation of covered-but-not-styled packages.
@item
Suggest refinements to the color palette.
@item
Help expand this document or any other piece of documentation.
@item
Merge requests for code refinements.
@end itemize

@xref{Merge requests, , Patches require copyright assignment to the FSF}.

It would be great if your feedback also includes some screenshots, GIFs,
or short videos, as well as further instructions to reproduce a given
setup.  Though this is not a requirement.

Whatever you do, bear in mind the overarching objective of the Modus
themes: to keep a contrast ratio that is greater or equal to 7:1 between
background and foreground colors.  If a compromise is ever necessary
between aesthetics and accessibility, it shall always be made in the
interest of the latter.

@node Merge requests
@section Patches require copyright assignment to the FSF

Code contributions are most welcome.  For any major edit (more than 15
lines, or so, in aggregate per person), you need to make a copyright
assignment to the Free Software Foundation.  This is necessary because
the themes are part of the upstream Emacs distribution: the FSF must at
all times be in a position to enforce the GNU General Public License.

Copyright assignment is a simple process.  Check the request form below
(please adapt it accordingly).  You must write an email to the address
mentioned in the form and then wait for the FSF to send you a legal
agreement.  Sign the document and file it back to them.  This could all
happen via email and take about a week.  You are encouraged to go
through this process.  You only need to do it once.  It will allow you
to make contributions to Emacs in general.

@example
Please email the following information to assign@@gnu.org, and we
will send you the assignment form for your past and future changes.

Please use your full legal name (in ASCII characters) as the subject
line of the message.
----------------------------------------------------------------------
REQUEST: SEND FORM FOR PAST AND FUTURE CHANGES

[What is the name of the program or package you're contributing to?]

GNU Emacs

[Did you copy any files or text written by someone else in these changes?
Even if that material is free software, we need to know about it.]

Copied a few snippets from the same files I edited.  Their author,
Protesilaos Stavrou, has already assigned copyright to the Free Software
Foundation.

[Do you have an employer who might have a basis to claim to own
your changes?  Do you attend a school which might make such a claim?]


[For the copyright registration, what country are you a citizen of?]


[What year were you born?]


[Please write your email address here.]


[Please write your postal address here.]





[Which files have you changed so far, and which new files have you written
so far?]

Changed a couple of themes that are part of the Emacs source code:

./etc/themes/modus-operandi-theme.el
./etc/themes/modus-vivendi-theme.el
@end example

@node Acknowledgements
@chapter Acknowledgements

The Modus themes are a collective effort.  Every contribution counts.

@table @asis
@item Author/maintainer
Protesilaos Stavrou.

@item Code contributions
Anders Johansson, Basil L@. Contovounesios,
Markus Beppler, Matthew Stevenson.

@item Ideas and user feedback
Aaron Jensen, Adam Spiers, Alex Griffin,
Alex Peitsinis, Alexey Shmalko, Anders Johansson, André Alexandre
Gomes, Arif Rezai, Basil L@. Contovounesios, Damien Cassou, Dario
Gjorgjevski, David Edmondson, Davor Rotim, Divan Santana, Gerry
Agbobada, Gianluca Recchia, Iris Garcia, Len Trigg, Manuel Uberti,
Mark Burton, Markus Beppler, Michael Goldenberg, Murilo Pereira,
Nicolas De Jaeghere, Pierre Téchoueyres, Roman Rudakov, Ryan Phillips,
Shreyas Ragavan, Tassilo Horn, Thibaut Verron, Trey Merkley, Uri
Sharf, Utkarsh Singh, Vincent Foley.  As well as users: Ben,
Fourchaux, Fredrik, Moesasji, Nick, TheBlob42, dinko, doolio, jixiuf,
okamsn, tycho garen.

@item Packaging
Dhavan Vaidya (Debian), Stefan Kangas (core Emacs),
Stefan Monnier (GNU Elpa).

@item Inspiration for certain features
Fabrice Niessen (leuven-theme),
Bozhidar Batsov (zenburn-theme).
@end table

@node Meta
@chapter Meta

If you are curious about the principles that govern the development of
this project read the essay @uref{https://protesilaos.com/codelog/2020-03-17-design-modus-themes-emacs/, On the design of the Modus themes}
(2020-03-17).

Here are some more publications for those interested in the kind of work
that goes into this project (sometimes the commits also include details
of this sort):

@itemize
@item
@uref{https://protesilaos.com/codelog/2020-05-10-modus-operandi-palette-review/, Modus Operandi theme subtle palette review} (2020-05-10)
@item
@uref{https://protesilaos.com/codelog/2020-06-13-modus-vivendi-palette-review/, Modus Vivendi theme subtle palette review} (2020-06-13)
@item
@uref{https://protesilaos.com/codelog/2020-07-04-modus-themes-faint-colours/, Modus themes: new ``faint syntax'' option} (2020-07-04)
@item
@uref{https://protesilaos.com/codelog/2020-07-08-modus-themes-nuanced-colours/, Modus themes: major review of ``nuanced'' colours} (2020-07-08)
@item
@uref{https://protesilaos.com/codelog/2020-09-14-modus-themes-review-blues/, Modus themes: review of blue colours} (2020-09-14)
@end itemize

And here are the canonical sources for this project's documentation:

@table @asis
@item Manual
@uref{https://protesilaos.com/modus-themes}
@item Change Log
@uref{https://protesilaos.com/modus-themes-changelog}
@item Screenshots
@uref{https://protesilaos.com/modus-themes-pictures}
@end table

@node External projects (ports)
@chapter External projects (ports)

The present section documents projects that extend the scope of the
Modus themes.  The following list will be updated whenever relevant
information is brought to my attention.  If you already have or intend
to produce such a port, feel welcome @uref{https://protesilaos.com/contact, to contact me}.

@table @asis
@item Modus exporter
This is @uref{https://github.com/polaris64/modus-exporter, an Elisp library written by Simon Pugnet}.
Licensed under the terms of the GNU General Public License.  It is
meant to capture the color values of the active Modus theme (Operandi
or Vivendi) and output it as a valid theme for some other application.
@end table

@node GNU Free Documentation License
@appendix GNU Free Documentation License

@example
                GNU Free Documentation License
                 Version 1.3, 3 November 2008


 Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
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 Everyone is permitted to copy and distribute verbatim copies
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This License is a kind of "copyleft", which means that derivative
works of the document must themselves be free in the same sense.  It
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We have designed this License in order to use it for manuals for free
software, because free software needs free documentation: a free
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nothing but endorsements of your Modified Version by various
parties--for example, statements of peer review or that the text has
been approved by an organization as the authoritative definition of a
standard.

You may add a passage of up to five words as a Front-Cover Text, and a
passage of up to 25 words as a Back-Cover Text, to the end of the list
of Cover Texts in the Modified Version.  Only one passage of
Front-Cover Text and one of Back-Cover Text may be added by (or
through arrangements made by) any one entity.  If the Document already
includes a cover text for the same cover, previously added by you or
by arrangement made by the same entity you are acting on behalf of,
you may not add another; but you may replace the old one, on explicit
permission from the previous publisher that added the old one.

The author(s) and publisher(s) of the Document do not by this License
give permission to use their names for publicity for or to assert or
imply endorsement of any Modified Version.


5. COMBINING DOCUMENTS

You may combine the Document with other documents released under this
License, under the terms defined in section 4 above for modified
versions, provided that you include in the combination all of the
Invariant Sections of all of the original documents, unmodified, and
list them all as Invariant Sections of your combined work in its
license notice, and that you preserve all their Warranty Disclaimers.

The combined work need only contain one copy of this License, and
multiple identical Invariant Sections may be replaced with a single
copy.  If there are multiple Invariant Sections with the same name but
different contents, make the title of each such section unique by
adding at the end of it, in parentheses, the name of the original
author or publisher of that section if known, or else a unique number.
Make the same adjustment to the section titles in the list of
Invariant Sections in the license notice of the combined work.

In the combination, you must combine any sections Entitled "History"
in the various original documents, forming one section Entitled
"History"; likewise combine any sections Entitled "Acknowledgements",
and any sections Entitled "Dedications".  You must delete all sections
Entitled "Endorsements".


6. COLLECTIONS OF DOCUMENTS

You may make a collection consisting of the Document and other
documents released under this License, and replace the individual
copies of this License in the various documents with a single copy
that is included in the collection, provided that you follow the rules
of this License for verbatim copying of each of the documents in all
other respects.

You may extract a single document from such a collection, and
distribute it individually under this License, provided you insert a
copy of this License into the extracted document, and follow this
License in all other respects regarding verbatim copying of that
document.


7. AGGREGATION WITH INDEPENDENT WORKS

A compilation of the Document or its derivatives with other separate
and independent documents or works, in or on a volume of a storage or
distribution medium, is called an "aggregate" if the copyright
resulting from the compilation is not used to limit the legal rights
of the compilation's users beyond what the individual works permit.
When the Document is included in an aggregate, this License does not
apply to the other works in the aggregate which are not themselves
derivative works of the Document.

If the Cover Text requirement of section 3 is applicable to these
copies of the Document, then if the Document is less than one half of
the entire aggregate, the Document's Cover Texts may be placed on
covers that bracket the Document within the aggregate, or the
electronic equivalent of covers if the Document is in electronic form.
Otherwise they must appear on printed covers that bracket the whole
aggregate.


8. TRANSLATION

Translation is considered a kind of modification, so you may
distribute translations of the Document under the terms of section 4.
Replacing Invariant Sections with translations requires special
permission from their copyright holders, but you may include
translations of some or all Invariant Sections in addition to the
original versions of these Invariant Sections.  You may include a
translation of this License, and all the license notices in the
Document, and any Warranty Disclaimers, provided that you also include
the original English version of this License and the original versions
of those notices and disclaimers.  In case of a disagreement between
the translation and the original version of this License or a notice
or disclaimer, the original version will prevail.

If a section in the Document is Entitled "Acknowledgements",
"Dedications", or "History", the requirement (section 4) to Preserve
its Title (section 1) will typically require changing the actual
title.


9. TERMINATION

You may not copy, modify, sublicense, or distribute the Document
except as expressly provided under this License.  Any attempt
otherwise to copy, modify, sublicense, or distribute it is void, and
will automatically terminate your rights under this License.

However, if you cease all violation of this License, then your license
from a particular copyright holder is reinstated (a) provisionally,
unless and until the copyright holder explicitly and finally
terminates your license, and (b) permanently, if the copyright holder
fails to notify you of the violation by some reasonable means prior to
60 days after the cessation.

Moreover, your license from a particular copyright holder is
reinstated permanently if the copyright holder notifies you of the
violation by some reasonable means, this is the first time you have
received notice of violation of this License (for any work) from that
copyright holder, and you cure the violation prior to 30 days after
your receipt of the notice.

Termination of your rights under this section does not terminate the
licenses of parties who have received copies or rights from you under
this License.  If your rights have been terminated and not permanently
reinstated, receipt of a copy of some or all of the same material does
not give you any rights to use it.


10. FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions of the
GNU Free Documentation License from time to time.  Such new versions
will be similar in spirit to the present version, but may differ in
detail to address new problems or concerns.  See
https://www.gnu.org/licenses/.

Each version of the License is given a distinguishing version number.
If the Document specifies that a particular numbered version of this
License "or any later version" applies to it, you have the option of
following the terms and conditions either of that specified version or
of any later version that has been published (not as a draft) by the
Free Software Foundation.  If the Document does not specify a version
number of this License, you may choose any version ever published (not
as a draft) by the Free Software Foundation.  If the Document
specifies that a proxy can decide which future versions of this
License can be used, that proxy's public statement of acceptance of a
version permanently authorizes you to choose that version for the
Document.

11. RELICENSING

"Massive Multiauthor Collaboration Site" (or "MMC Site") means any
World Wide Web server that publishes copyrightable works and also
provides prominent facilities for anybody to edit those works.  A
public wiki that anybody can edit is an example of such a server.  A
"Massive Multiauthor Collaboration" (or "MMC") contained in the site
means any set of copyrightable works thus published on the MMC site.

"CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0
license published by Creative Commons Corporation, a not-for-profit
corporation with a principal place of business in San Francisco,
California, as well as future copyleft versions of that license
published by that same organization.

"Incorporate" means to publish or republish a Document, in whole or in
part, as part of another Document.

An MMC is "eligible for relicensing" if it is licensed under this
License, and if all works that were first published under this License
somewhere other than this MMC, and subsequently incorporated in whole or
in part into the MMC, (1) had no cover texts or invariant sections, and
(2) were thus incorporated prior to November 1, 2008.

The operator of an MMC Site may republish an MMC contained in the site
under CC-BY-SA on the same site at any time before August 1, 2009,
provided the MMC is eligible for relicensing.


ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and
license notices just after the title page:

    Copyright (c)  YEAR  YOUR NAME.
    Permission is granted to copy, distribute and/or modify this document
    under the terms of the GNU Free Documentation License, Version 1.3
    or any later version published by the Free Software Foundation;
    with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
    A copy of the license is included in the section entitled "GNU
    Free Documentation License".

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts,
replace the "with...Texts." line with this:

    with the Invariant Sections being LIST THEIR TITLES, with the
    Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.

If you have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
situation.

If your document contains nontrivial examples of program code, we
recommend releasing these examples in parallel under your choice of
free software license, such as the GNU General Public License,
to permit their use in free software.
@end example

@bye