Protesilaos Stavrou

Standard themes for GNU Emacs

Like the default theme but more consistent.

This manual, written by Protesilaos Stavrou, describes the Emacs package called standard-themes, and provides every other piece of information pertinent to it.

The documentation furnished herein corresponds to stable version 2.1.0, released on 2024-08-11. Any reference to a newer feature which does not yet form part of the latest tagged commit, is explicitly marked as such.

Current development target is 2.2.0-dev.

If you are viewing the README.org version of this file, please note that the GNU ELPA machinery automatically generates an Info manual out of it.

1. COPYING

Copyright (C) 2022-2023 Free Software Foundation, Inc.

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 the Front-Cover Texts being “A GNU Manual,” and with the Back-Cover Texts as in (a) below. A copy of the license is included in the section entitled “GNU Free Documentation License.”

(a) The FSF’s Back-Cover Text is: “You have the freedom to copy and modify this GNU manual.”

2. About the Standard themes

The standard-themes are a collection of light and dark themes for GNU Emacs. The standard-light and standard-dark emulate the out-of-the-box looks of Emacs (which technically do NOT constitute a theme) while bringing to them thematic consistency, customizability, and extensibility. Other themes are stylistic variations of those.

Why call them “standard”? Obviously because: Standard Themes Are Not Derivatives but the Affectionately Reimagined Default … themes.

3. Installation

3.1. GNU ELPA package

The package is available as standard-themes. Simply do: 

M-x package-refresh-contents
M-x package-install

And search for it.

GNU ELPA provides the latest stable release. Those who prefer to follow the development process in order to report bugs or suggest changes, can use the version of the package from the GNU-devel ELPA archive. Read: https://protesilaos.com/codelog/2022-05-13-emacs-elpa-devel/.

3.2. Manual installation

Assuming your Emacs files are found in ~/.emacs.d/, execute the following commands in a shell prompt: 

cd ~/.emacs.d

# Create a directory for manually-installed packages
mkdir manual-packages

# Go to the new directory
cd manual-packages

# Clone this repo, naming it "standard-themes"
git clone https://github.com/protesilaos/standard-themes standard-themes

Finally, in your init.el (or equivalent) evaluate this: 

;; Make Elisp files in that directory available to the user.
(add-to-list 'load-path "~/.emacs.d/manual-packages/standard-themes")

Everything is in place to set up the package.

4. Sample configuration

;; Make customisations that affect Emacs faces BEFORE loading a theme
;; (any change needs a theme re-load to take effect).
(require 'standard-themes)

;; Read the doc string of each of those user options.  These are some
;; sample values.
(setq standard-themes-bold-constructs t
      standard-themes-italic-constructs t
      standard-themes-disable-other-themes t
      standard-themes-mixed-fonts t
      standard-themes-variable-pitch-ui t
      standard-themes-prompts '(extrabold italic)
      standard-themes-to-toggle '(standard-light standard-dark)
      standard-themes-to-rotate '(standard-light standard-light-tinted standard-dark standard-dark-tinted)

      ;; more complex alist to set weight, height, and optional
      ;; `variable-pitch' per heading level (t is for any level not
      ;; specified):
      standard-themes-headings
      '((0 . (variable-pitch light 1.9))
        (1 . (variable-pitch light 1.8))
        (2 . (variable-pitch light 1.7))
        (3 . (variable-pitch semilight 1.6))
        (4 . (variable-pitch semilight 1.5))
        (5 . (variable-pitch 1.4))
        (6 . (variable-pitch 1.3))
        (7 . (variable-pitch 1.2))
        (agenda-date . (1.3))
        (agenda-structure . (variable-pitch light 1.8))
        (t . (variable-pitch 1.1))))

;; All the Standard themes are listed in `standard-themes-items'.
(standard-themes-load-theme 'standard-light)

(define-key global-map (kbd "<f5>") #'standard-themes-toggle)
(define-key global-map (kbd "M-<f5>") #'standard-themes-rotate)

5. Customization options

The standard-themes provide user options which tweak secondary aspects of the theme. All customizations need to be evaluated before loading a theme. Any change after the theme has been loaded requires a re-load (Loading a theme).

5.1. Option to disable other themes

The user option standard-themes-disable-other-themes controls whether to disable other themes when loading a Standard theme (Loading a theme).

When the value is non-nil, the command standard-themes-toggle as well as the functions standard-themes-load-dark and standard-themes-load-light, will disable all other themes while loading the given Standard theme. This is done to ensure that Emacs does not blend two or more themes: such blends lead to awkward results that undermine the work of the designer.

When the value is nil, the aforementioned command and functions will only disable the other Standard theme.

This option is provided because Emacs themes are not necessarily limited to colors/faces: they can consist of an arbitrary set of customizations. Users who use such customization bundles must set this variable to a nil value.

5.2. Option for themes to toggle

[ Part of 2.2.0-dev. ]

The user option standard-themes-to-toggle is a list of Standard themes to switch between when using the command standard-themes-toggle.

The list must include two items. If there are more, they are ignored.

5.3. Option for themes to rotate

[ Part of 2.2.0-dev. ]

The user option standard-themes-to-rotate is a list of Standard themes to switch between when using the command standard-themes-rotate.

5.4. Option to enable mixed fonts

The user option standard-themes-mixed-fonts controls whether strictly spacing-sensitive constructs inherit from fixed-pitch (a monospaced font family) to ensure proper alignment at all times.

By default (a nil value for this user option) no face inherits from fixed-pitch: they all use the default font family, regardless of whether it is monospaced or not.

When standard-themes-mixed-fonts is set to a non-nil value, faces such as for Org tables, inline code, code blocks, and the like, are rendered in a monospaced font (the inherit the fixed-pitch face). The user can thus set their default font family to a proportionately spaced font without worrying about breaking the alignment of relevant elements (or if they simply prefer the aesthetics of mixed mono and proportionately spaced font families).

A temporary switch to a proportionately spaced font (known in Emacs as variable-pitch) can be enabled in the current buffer with the activation of the built-in variable-pitch-mode. Mixed fonts work well in this case.

To get consistent typography, the user may need to edit the font family of the fixed-pitch and variable-pitch faces. The fontaine package on GNU ELPA (by Protesilaos) can be helpful in this regard.

5.5. Option to control the UI typeface

The user option standard-themes-variable-pitch-ui controls whether the elements of the User Interface (UI) use a proportionately spaced font.

By default (a nil value), all UI elements use the default font family. When this user option is set to a non-nil value, all UI elements will inherit the face variable-pitch, thus rendering them in a proportionately spaced font.

In this context, the UI elements are:

  • header-line
  • mode-line (active and inactive)
  • tab-bar-mode
  • tab-line-mode

To get consistent typography, the user may need to edit the font family of the fixed-pitch and variable-pitch faces. The fontaine package on GNU ELPA (by Protesilaos) can be helpful in this regard.

5.6. Option to enable more bold constructs

The user option standard-themes-bold-constructs determines whether select faces will inherit the bold face. When the value is non-nil, a bold weight is applied to code constructs. This affects keywords, builtins, and a few other elements.

Configure bold and italic faces.

5.7. Option to enable more italic constructs

The user option standard-themes-italic-constructs determines whether select faces will inherit the italic face. When the value is non-nil, an italic style is applied to code constructs. This affects comments, doc strings, and a few other minor elements.

Configure bold and italic faces.

5.8. Option for command prompts

The user option standard-themes-prompts controls the style of all prompts, such as those of the minibuffer and REPLs.

Possible values are expressed as a list of properties (default is nil or an empty list). The list can include any of the following symbols:

  • italic
  • A font weight, which must be supported by the underlying typeface:
    • thin
    • ultralight
    • extralight
    • light
    • semilight
    • regular
    • medium
    • semibold
    • bold
    • heavy
    • extrabold
    • ultrabold

The default (a nil value or an empty list) means to only use a foreground color without any typographic additions.

The italic property adds a slant to the font’s forms (italic or oblique forms, depending on the typeface).

The symbol of a font weight attribute such as light, semibold, et cetera, adds the given weight to links. Valid symbols are defined in the variable standard-themes-weights. The absence of a weight means that the one of the underlying text will be used.

Combinations of any of those properties are expressed as a list, like in these examples: 

(bold italic)
(italic semibold)

The order in which the properties are set is not significant.

In user configuration files the form may look like this: 

(setq standard-themes-prompts '(extrabold italic))

The foreground and background colors of prompts can be modified by applying palette overrides (Palette overrides).

5.9. Option for headings

The user option standard-themes-headings provides support for individual heading styles for regular heading levels 0 through 8, as well as the Org agenda headings.

This is an alist that accepts a (KEY . LIST-OF-VALUES) combination. The KEY is either a number, representing the heading’s level (0 through 8) or t, which pertains to the fallback style. The named keys agenda-date and agenda-structure apply to the Org agenda.

Level 0 is a special heading: it is used for what counts as a document title or equivalent, such as the #+title construct we find in Org files. Levels 1-8 are regular headings.

The LIST-OF-VALUES covers symbols that refer to properties, as described below. Here is a complete sample with various stylistic combinations, followed by a presentation of all available properties: 

(setq standard-themes-headings
      '((1 . (variable-pitch 1.5))
        (2 . (1.3))
        (agenda-date . (1.3))
        (agenda-structure . (variable-pitch light 1.8))
        (t . (1.1))))

Properties:

  • A font weight, which must be supported by the underlying typeface:
    • thin
    • ultralight
    • extralight
    • light
    • semilight
    • regular
    • medium
    • semibold
    • bold (default)
    • heavy
    • extrabold
    • ultrabold
  • A floating point as a height multiple of the default or a cons cell in the form of (height . FLOAT).

By default (a nil value for this variable), all headings have a bold typographic weight and use a desaturated text color.

A variable-pitch property changes the font family of the heading to that of the variable-pitch face (normally a proportionately spaced typeface).

The symbol of a weight attribute adjusts the font of the heading accordingly, such as light, semibold, etc. Valid symbols are defined in the variable standard-themes-weights. The absence of a weight means that bold will be used by virtue of inheriting the bold face.

A number, expressed as a floating point (e.g. 1.5), adjusts the height of the heading to that many times the base font size. The default height is the same as 1.0, though it need not be explicitly stated. Instead of a floating point, an acceptable value can be in the form of a cons cell like (height . FLOAT) or (height FLOAT), where FLOAT is the given number.

Combinations of any of those properties are expressed as a list, like in these examples: 

(semibold)
(variable-pitch semibold 1.3)
(variable-pitch semibold (height 1.3)) ; same as above
(variable-pitch semibold (height . 1.3)) ; same as above

The order in which the properties are set is not significant.

In user configuration files the form may look like this: 

(setq standard-themes-headings
      '((1 . (variable-pitch 1.5))
        (2 . (1.3))
        (agenda-date . (1.3))
        (agenda-structure . (variable-pitch light 1.8))
        (t . (1.1))))

When defining the styles per heading level, it is possible to pass a non-nil value (t) instead of a list of properties. This will retain the original aesthetic for that level. For example: 

(setq standard-themes-headings
      '((1 . t)           ; keep the default style
        (2 . (semibold 1.2))
        (t . (rainbow)))) ; style for all other headings

(setq standard-themes-headings
      '((1 . (variable-pitch 1.5))
        (2 . (semibold))
        (t . t))) ; default style for all other levels

Note that the text color of headings, of their background, and overline can all be set via the overrides. It is possible to have any color combination for any heading level (something that could not be done in older versions of the themes).

The foreground, background, and overline colors of headings can be modified by applying palette overrides (Palette overrides).

5.10. Palette overrides

The Standard themes define their own color palette as well as semantic color mappings. The former is the set of color values such as what shade of blue to use. The latter refers to associations between a color value and a syntactic construct, such as a variable for variables in programming modes or heading-1 for level 1 headings in Org and others.

The definition is stored in the variable NAME-palette, where NAME is the symbol of the theme, such as standard-light. Overrides for those associations are specified in the variable NAME-palette-overrides.

The variable standard-themes-common-palette-overrides is available for shared values. It is advised to only use this for mappings that do not specify a color value directly. This way, the text remains legible by getting the theme-specific color value it needs.

All associations take the form of (KEY VALUE) pairs. For example, the standard-light-palette contains (blue-warmer "#3a5fcd"). Semantic color mappings are the same, though the VALUE is one of the named colors of the theme. For instance, standard-light-palette maps the aforementioned like (link blue-warmer).

The easiest way to learn about a theme’s definition is to use the command describe-variable (bound to C-h v by default) and then search for the NAME-palette. The resulting Help buffer will look like this: 

standard-light-palette is a variable defined in ‘standard-light-theme.el’.

Its value is shown below.

The ‘standard-light’ palette.

  This variable may be risky if used as a file-local variable.

Value:
((bg-main "#ffffff")
 (fg-main "#000000")
 (bg-dim "#ededed")

[... Shortened for the purposes of this manual.]

The user can study this information to identify the overrides they wish to make. Then they can specify them and re-load the theme for changes to take effect. Sample of how to override a color value and a semantic mapping: 

(setq standard-light-palette-overrides
      '((blue-warmer "#5230ff") ; original value is #3a5fcd
        (variable blue-warmer))) ; original value is yellow-cooler

The overrides can contain as many associations as the user needs.

Changes to color values are reflected in the preview of the theme’s palette (Preview theme colors). They are shown at the top of the buffer. In the above example, the first instance of blue-warmer is the override and the second is the original one.

Contact me if you need further help with this.

6. Loading a theme

Emacs can load and maintain enabled multiple themes at once. This typically leads to awkward styling and weird combinations. The theme looks broken and the designer’s intent is misunderstood. Before loading either of the standard-themes, the user is encouraged to disable all others (Disable other themes): 

(mapc #'disable-theme custom-enabled-themes)

Then load the theme of choice. For example: 

(load-theme 'standard-light :no-confirm)

The :no-confirm is optional. It simply skips the step where Emacs asks the user whether they are sure about loading the theme.

Consider adding code like the above to the user configuration file, such as init.el.

As the Standard themes are extensible, another way to load the theme of choice is to use either standard-themes-load-dark or standard-themes-load-light. These functions take care to (i) disable other themes, (ii) load the specified Standard theme, and (iii) run the standard-themes-post-load-hook which is useful for do-it-yourself customizations (The general approach to DIY changes). These two functions are also called by the command standard-themes-toggle.

7. Preview theme colors

The command standard-themes-preview-colors uses minibuffer completion to select an item from the Standard themes and then produces a buffer with previews of its color palette entries. The buffer has a naming scheme which reflects the given choice, like standard-light-preview-colors for the standard-light theme.

The command standard-themes-preview-colors-current skips the minibuffer selection process and just produces a preview for the current Standard theme.

When called with a prefix argument (C-u with the default key bindings), these commands will show a preview of the palette’s semantic color mappings instead of the named colors.

Aliases for those commands are standard-themes-list-colors and standard-themes-list-colors-current.

Overrides to color values are reflected in the buffers produced by the aforementioned commands (Palette overrides).

Each row shows a foreground and background coloration using the underlying value it references. For example a line with #b3303a (a shade of red) will show red text followed by a stripe with that same color as a backdrop.

The name of the buffer describes the given Standard theme and what the contents are, such as *standard-light-list-colors* for named colors and =*standard-light-list-mappings* for the semantic color mappings.

8. Use colors from the active Standard theme

Advanced users may want to call color variables from the palette of the active Standard theme. The macro standard-themes-with-colors supplies those to any form called inside of it. For example: 

(standard-themes-with-colors
  (list bg-main fg-main bg-mode-line))
;; => ("#ffffff" "#000000" "#b3b3b3")

The above return value is for standard-light when that is the active Standard theme. Switching to standard-dark and evaluating this code anew will give us the relevant results for that theme: 

(standard-themes-with-colors
  (list bg-main fg-main bg-mode-line cursor))
;; => ("#000000" "#ffffff" "#505050")

Do-It-Yourself customizations.

The palette of each Standard theme is considered stable. No removals shall be made. Though please note that some tweaks to individual hues or color mapping are still possible. At any rate, we will not outright break any code that uses standard-themes-with-colors.

9. Do-It-Yourself customizations

This section shows how the user can tweak the Standard themes to their liking, often by employing the standard-themes-with-colors macro (Use colors from the active Standard theme).

9.1. Get a single color from the palette

The general approach to advanced DIY changes.

The fuction standard-themes-get-color-value can be called from Lisp to return the value of a color from the active Standard theme palette. It takea a COLOR argument and an optional OVERRIDES.

COLOR is a symbol that represents a named color entry in the palette.

Preview theme colors.

If the value is the name of another color entry in the palette (so a mapping), this function recurs until it finds the underlying color value.

With an optional OVERRIDES argument as a non-nil value, it accounts for palette overrides. Else it reads only the default palette.

Palette overrides.

With optional THEME as a symbol among standard-themes-collection, use the palette of that item. Else use the current Standard theme.

If COLOR is not present in the palette, this function returns the unspecified symbol, which is safe when used as a face attribute’s value.

An example with standard-light to show how this function behaves with/without overrides and when recursive mappings are introduced. 

;; Here we show the recursion of palette mappings.  In general, it is
;; better for the user to specify named colors to avoid possible
;; confusion with their configuration, though those still work as
;; expected.
(setq standard-themes-common-palette-overrides
      '((cursor red)
        (prompt cursor)
        (variable prompt)))

;; Ignore the overrides and get the original value.
(standard-themes-get-color-value 'variable)
;; => "#a0522d"

;; Read from the overrides and deal with any recursion to find the
;; underlying value.
(standard-themes-get-color-value 'variable :overrides)
;; => "#b3303a"

9.2. The general approach to advanced DIY changes

When the user wants to customize Emacs faces there are two considerations they need to make if they care about robustness:

  1. Do not hardcode color values, but instead use the relevant variables from the Standard themes.
  2. Make the changes persist through theme changes between the Standard themes.

For point 1 we provide the standard-themes-with-colors macro, while for point 2 we have the standard-themes-post-load-hook. The hook runs at the end of the command standard-themes-toggle.

Use colors from the active Standard theme.

A theme-agnostic hook for theme loading.

We need to wrap our code in the standard-themes-with-colors and declare it as a function which we then add to the hook. Here we show the general approach of putting those pieces together.

To customize faces in a way that mirrors the Standard themes’ source code, we use the built-in custom-set-faces. The value it accepts has the same syntax as that found in standard-themes.el, specifically the standard-themes-faces constant. It thus is easy to copy lines from there and tweak them. Let’s pick a couple of font-lock faces (used in all programming modes, among others): 

(defun my-standard-themes-custom-faces ()
  "My customizations on top of the Standard themes.
This function is added to the `standard-themes-post-load-hook'."
  (standard-themes-with-colors
    (custom-set-faces
     ;; These are the default specifications
     `(font-lock-comment-face ((,c :inherit standard-themes-italic :foreground ,comment)))
     `(font-lock-variable-name-face ((,c :foreground ,variable))))))

;; Using the hook lets our changes persist when we use the commands
;; `standard-themes-toggle', `standard-themes-load-dark',
;; `standard-themes-load-light'.
(add-hook 'standard-themes-post-load-hook #'my-standard-themes-custom-faces)

Each of the Standard themes has its own color palette and corresponding mapping of values to constructs. So the color of the comment variable will differ between the themes. For the purpose of our demonstration, we make variables look like comments and comments like variables: 

(defun my-standard-themes-custom-faces ()
  "My customizations on top of the Standard themes.
This function is added to the `standard-themes-post-load-hook'."
  (standard-themes-with-colors
    (custom-set-faces
     `(font-lock-comment-face ((,c :foreground ,variable)))
     `(font-lock-variable-name-face ((,c :inherit standard-themes-italic :foreground ,comment))))))

;; Using the hook lets our changes persist when we use the commands
;; `standard-themes-toggle', `standard-themes-load-dark',
;; `standard-themes-load-light'.
(add-hook 'standard-themes-post-load-hook #'my-standard-themes-custom-faces)

All changes take effect when a theme is loaded again. As such, it is better to use either standard-themes-load-dark or standard-themes-load-light at startup so that the function added to the hook gets applied properly upon first load. Like this: 

(defun my-standard-themes-custom-faces ()
  "My customizations on top of the Standard themes.
This function is added to the `standard-themes-post-load-hook'."
  (standard-themes-with-colors
    (custom-set-faces
     `(font-lock-comment-face ((,c :foreground ,variable)))
     `(font-lock-variable-name-face ((,c :inherit standard-themes-italic :foreground ,comment))))))

;; Using the hook lets our changes persist when we use the commands
;; `standard-themes-toggle', `standard-themes-load-dark',
;; `standard-themes-load-light'.
(add-hook 'standard-themes-post-load-hook #'my-standard-themes-custom-faces)

;; Load the theme and run `standard-themes-post-load-hook'
(standard-themes-load-light) ; OR (standard-themes-load-dark)

Please contact us if you have specific questions about this mechanism. We are willing to help and shall provide comprehensive documentation where necessary.

9.3. A theme-agnostic hook for theme loading

The themes are designed with the intent to be useful to Emacs users of varying skill levels, from beginners to experts. This means that we try to make things easier by not expecting anyone reading this document to be proficient in Emacs Lisp or programming in general.

Such a case is with the use of the standard-themes-post-load-hook, which is called after the evaluation of any of the commands we provide for loading a theme (Loading a theme). We recommend using that hook for advanced customizations, because (1) we know for sure that it is available once the themes are loaded, and (2) anyone consulting this manual, especially the sections on enabling and loading the themes, will be in a good position to benefit from that hook.

Advanced users who have a need to switch between the Standard themes and other items (e.g. the modus-themes and ef-themes) will find that such a hook does not meet their requirements: it only works with the Standard themes and only with the functions they provide.

A theme-agnostic setup can be configured thus: 

(defvar after-enable-theme-hook nil
   "Normal hook run after enabling a theme.")

(defun run-after-enable-theme-hook (&rest _args)
   "Run `after-enable-theme-hook'."
   (run-hooks 'after-enable-theme-hook))

(advice-add 'enable-theme :after #'run-after-enable-theme-hook)

This creates the after-enable-theme-hook and makes it run after each call to enable-theme, which means that it will work for all themes and also has the benefit that it does not depend on functions such as standard-themes-select and the others mentioned in this manual. The function enable-theme is called internally by load-theme, so the hook works everywhere.

The downside of the theme-agnostic hook is that any functions added to it will likely not be able to benefit from macro calls that read the active theme, such as standard-themes-with-colors (the Modus and Ef themes have an equivalent macro). Not all Emacs themes have the same capabilities.

In this document, we always mention standard-themes-post-load-hook though the user can replace it with after-enable-theme-hook should they need to (provided they understand the implications).

9.4. Add support for hl-todo

The hl-todo package provides the user option hl-todo-keyword-faces: it specifies an association list of (KEYWORD . COLOR-VALUE) pairs. There are no faces, which the theme could style seamlessly. As such, it rests on the user to specify appropriate color values. This can be done either by hardcoding colors, which is inefficient, or by using the macro standard-themes-with-colors (The general approach to DIY changes). Here we show the latter method. 

(defun my-standard-themes-hl-todo-faces ()
  "Configure `hl-todo-keyword-faces' with Standard themes colors.
The exact color values are taken from the active Standard theme."
  (standard-themes-with-colors
    (setq hl-todo-keyword-faces
          `(("HOLD" . ,yellow)
            ("TODO" . ,red)
            ("NEXT" . ,blue)
            ("THEM" . ,magenta)
            ("PROG" . ,cyan-warmer)
            ("OKAY" . ,green-warmer)
            ("DONT" . ,yellow-warmer)
            ("FAIL" . ,red-warmer)
            ("BUG" . ,red-warmer)
            ("DONE" . ,green)
            ("NOTE" . ,blue-warmer)
            ("KLUDGE" . ,cyan)
            ("HACK" . ,cyan)
            ("TEMP" . ,red)
            ("FIXME" . ,red-warmer)
            ("XXX+" . ,red-warmer)
            ("REVIEW" . ,red)
            ("DEPRECATED" . ,yellow)))))

(add-hook 'standard-themes-post-load-hook #'my-standard-themes-hl-todo-faces)

To find the names of the color variables, the user can rely on the commands for previewing the palette (Preview theme colors).

9.5. Configure bold and italic faces

The Standard themes do not hardcode a :weight or :slant attribute in the faces they cover. Instead, they configure the generic faces called bold and italic to use the appropriate styles and then instruct all relevant faces that require emphasis to inherit from them.

This practically means that users can change the particularities of what it means for a construct to be bold/italic, by tweaking the bold and italic faces. Cases where that can be useful include:

  • The default typeface does not have a variant with slanted glyphs (e.g. Fira Mono/Code as of this writing on 2022-11-30), so the user wants to add another family for the italics, such as Hack.
  • The typeface of choice provides a multitude of weights and the user prefers the light one by default. To prevent the bold weight from being too heavy compared to the light one, they opt to make bold use a semibold weight.
  • The typeface distinguishes between oblique and italic forms by providing different font variants (the former are just slanted versions of the upright forms, while the latter have distinguishing features as well). In this case, the user wants to specify the font that applies to the italic face.

To achieve those effects, one must first be sure that the fonts they use have support for those features.

In this example, we set the default font family to Fira Code, while we choose to render italics in the Hack typeface (obviously one needs to pick fonts that work in tandem): 

(set-face-attribute 'default nil :family "Fira Code" :height 110)
(set-face-attribute 'italic nil :family "Hack")

And here we play with different weights, using Source Code Pro: 

(set-face-attribute 'default nil :family "Source Code Pro" :height 110 :weight 'light)
(set-face-attribute 'bold nil :weight 'semibold)

To reset the font family, one can use this: 

(set-face-attribute 'italic nil :family 'unspecified)

Consider the fontaine package on GNU ELPA (by Protesilaos) which provides the means to configure font families via faces.

9.6. Tweak org-modern timestamps

The org-modern package uses faces and text properties to make Org buffers more aesthetically pleasing. It affects tables, timestamps, lists, headings, and more.

In previous versions of the Standard themes, we mistakenly affected one of its faces: the org-modern-label. It changed the intended looks and prevented the user option org-modern-label-border from having its desired effect. As such, we no longer override that face.

Users who were used to the previous design and who generally do not configure the user options of org-modern may thus notice a change in how clocktables (or generally tables with timestamps) are aligned. The simplest solution is to instruct the mode to not prettify timestamps, by setting the user option org-modern-timestamp to nil. For example, by adding this to the init file: 

(setq org-modern-timestamp nil)

Alignment in tables will also depend on the use of proportionately spaced fonts. Enable the relevant option to work with those without any further trouble (Enable mixed fonts).

For any further issues, you are welcome to ask for help.

9.7. Tweak goto-address-mode faces

The built-in goto-address-mode uses heuristics to identify URLs and email addresses in the current buffer. It then applies a face to them to change their style. Some packages, such as notmuch, use this minor-mode automatically.

The faces are not declared with defface, meaning that it is better that the theme does not modify them. The user is thus encouraged to consider including this in their setup: 

(setq goto-address-url-face 'link
      goto-address-url-mouse-face 'highlight
      goto-address-mail-face 'link
      goto-address-mail-mouse-face 'highlight)

My personal preference is to set goto-address-mail-face to nil, because it otherwise adds too much visual noise to the buffer (email addresses stand out more, due to the use of the uncommon @ caharacter but also because they are often enclosed in angled brackets).

10. Faces defined by the Standard themes

The themes define some faces to make it possible to achieve consistency between various groups of faces. For example, all “marks for selection” use the standard-themes-mark-select face. If, say, the user wants to edit this face to include an underline, the change will apply to lots of packages, like Dired, Trashed, Ibuffer.

Do-It-Yourself customizations.

All the faces defined by the themes:

  • standard-themes-bold
  • standard-themes-fixed-pitch
  • standard-themes-fringe-error
  • standard-themes-fringe-info
  • standard-themes-fringe-warning
  • standard-themes-heading-0
  • standard-themes-heading-1
  • standard-themes-heading-2
  • standard-themes-heading-3
  • standard-themes-heading-4
  • standard-themes-heading-5
  • standard-themes-heading-6
  • standard-themes-heading-7
  • standard-themes-heading-8
  • standard-themes-intense-blue
  • standard-themes-intense-cyan
  • standard-themes-intense-green
  • standard-themes-intense-magenta
  • standard-themes-intense-red
  • standard-themes-intense-yellow
  • standard-themes-italic
  • standard-themes-key-binding
  • standard-themes-mark-delete
  • standard-themes-mark-other
  • standard-themes-mark-select
  • standard-themes-nuanced-blue
  • standard-themes-nuanced-cyan
  • standard-themes-nuanced-green
  • standard-themes-nuanced-magenta
  • standard-themes-nuanced-red
  • standard-themes-nuanced-yellow
  • standard-themes-prompt
  • standard-themes-subtle-blue
  • standard-themes-subtle-cyan
  • standard-themes-subtle-green
  • standard-themes-subtle-magenta
  • standard-themes-subtle-red
  • standard-themes-subtle-yellow
  • standard-themes-ui-variable-pitch
  • standard-themes-underline-error
  • standard-themes-underline-info
  • standard-themes-underline-warning

11. Supported packages or face groups

The standard-themes will only ever support a curated list of packages based on my judgement (Packages that are hard to support). Nevertheless, the list of explicitly or implicitly supported packages already covers everything most users need.

11.1. Explicitly supported packages or face groups

  • all basic faces
  • all-the-icons
  • all-the-icons-dired
  • all-the-icons-ibuffer
  • ansi-color
  • auctex
  • auto-dim-other-buffers
  • breadcrumb
  • bongo
  • bookmark
  • calendar and diary
  • cider
  • centaur-tabs
  • change-log and log-view (part of VC)
  • chart
  • clojure-mode
  • company
  • compilation
  • completions
  • consult
  • corfu
  • corfu-candidate-overlay
  • custom (M-x customize)
  • denote
  • dictionary
  • diff-hl
  • diff-mode
  • dired
  • dired-subtree
  • diredfl
  • dirvish
  • display-fill-column-indicator-mode
  • doom-modeline
  • ediff
  • eglot
  • eldoc
  • elfeed
  • embark
  • epa
  • erc
  • ert
  • eshell
  • eww
  • flycheck
  • flymake
  • flyspell
  • font-lock
  • git-commit
  • git-rebase
  • gnus
  • hi-lock (M-x highlight-regexp)
  • ibuffer
  • image-dired
  • info
  • isearch, occur, query-replace
  • jit-spell
  • keycast
  • lin [ Part of 2.2.0-dev. ]
  • line numbers (display-line-numbers-mode and global variant)
  • magit
  • man
  • marginalia
  • markdown-mode
  • messages
  • mode-line
  • mu4e
  • nerd-icons
  • nerd-icons-completion
  • nerd-icons-dired
  • nerd-icons-ibuffer
  • neotree
  • notmuch
  • olivetti
  • orderless
  • org
  • org-habit
  • org-modern
  • outline-mode
  • outline-minor-faces
  • package (M-x list-packages)
  • perspective
  • powerline
  • pulsar [ Part of 2.2.0-dev. ]
  • pulse
  • rainbow-delimiters
  • rcirc
  • recursion-indicator
  • regexp-builder (re-builder)
  • ruler-mode
  • shell-script-mode (sh-mode)
  • show-paren-mode
  • shr
  • smerge
  • tab-bar-mode
  • tab-line-mode
  • tempel
  • term
  • textsec
  • transient
  • trashed
  • tree-sitter
  • tty-menu
  • vc (vc-dir.el, vc-hooks.el)
  • vertico
  • vundo
  • wgrep
  • which-function-mode
  • which-key
  • whitespace-mode
  • widget
  • writegood-mode
  • woman
  • ztree

11.2. Implicitly supported packages or face groups

Those are known to work with the Standard themes either because their colors are appropriate or because they inherit from basic faces which the themes already cover:

  • apropos
  • dim-autoload
  • hl-todo
  • icomplete
  • ido
  • multiple-cursors
  • paren-face
  • which-key
  • xref

Note that “implicitly supported” does not mean that they always fit in perfectly. If there are refinements we need to made, then we need to intervene (Explicitly supported packages or face groups).

11.3. Packages that are hard to support

These are difficult to support due to their (i) incompatibility with the design of the standard-themes, (ii) complexity or multiple points of entry, (iii) external dependencies, (iv) existence of better alternatives in my opinion, or (v) inconsiderate use of color out-of-the-box and implicit unwillingness to be good Emacs citizens:

avy
its UI is prone to visual breakage and is hard to style correctly.
calibredb
has an external dependency that I don’t use.
ctrlf
use the built-in isearch or the consult-line command of consult.
dired+
it is complex and makes inconsiderate use of color.
ein (Emacs IPython Notebook)
external dependency that I don’t use.
ement.el
has an external dependency that I don’t use.
helm
it is complex and makes inconsiderate use of color. Prefer the vertico, consult, and embark packages.
info+
it is complex and makes inconsiderate use of color.
ivy/counsel/swiper
use the vertico, consult, and embark packages which are designed to be compatible with standard Emacs mechanisms and are modular.
lsp-mode
has external dependencies that I don’t use.
solaire
in principle, it is incompatible with practically every theme that is not designed around it. Emacs does not distinguish between “UI” and “syntax” buffers.
sx
has an external dependency that I don’t use.
telega
has an external dependency that I don’t use (I don’t even have a smartphone).
treemacs
it has too many dependencies and does too many things.
web-mode
I don’t use all those Web technologies and cannot test this properly without support from an expert. It also defines lots of faces that hardcode color values for no good reason.

The above list is non-exhaustive though you get the idea.

12. Acknowledgements

This project is meant to be a collective effort. Every bit of help matters.

Author/maintainer
Protesilaos Stavrou.
Contributions to code
Clemens Radermacher.
Ideas and/or user feedback
Filippo Argiolas, Fritz Grabo, Manuel Uberti, Tassilo Horn, Zack Weinberg.

13. GNU Free Documentation License


                GNU Free Documentation License
                 Version 1.3, 3 November 2008


 Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
     
 Everyone is permitted to copy and distribute verbatim copies
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You may not copy, modify, sublicense, or distribute the Document
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10. FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions of the
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https://www.gnu.org/licenses/.

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The operator of an MMC Site may republish an MMC contained in the site
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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;
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    A copy of the license is included in the section entitled "GNU
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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.