SimplePlusNord-BeamerTheme

A light Beamer theme in the Nord colours, made for research talks.

Slides are light, with the title in a dark band. The title slide and the outline slides are dark. Every colour is one of the 16 Nord colours.

What is here

beamer.tex          the deck, start here (beamer.pdf is its compiled version)
meta/               info.tex (title, author, date) and reference.bib
slides/             one file per section, then the references and the thank-you slide
slides/img/         the pictures, and their credits
theme/              the theme: you never edit it
preview/            the images above

beamer.tex loads the theme, reads meta/info.tex and has one \input per file of slides/. The pictures are on the graphics path, so a slide just writes \includegraphics{graph.png}. In theme/ the four files are the usual Beamer ones: colours (with the Nord palette), fonts, inner theme (boxes, outline, code) and the main file with the options.

To learn the theme, read beamer.pdf next to slides/: each slide shows one thing and the code behind it.

Start a deck

Copy the folder, replace the files in slides/ with your own sections (keep the \input lines of beamer.tex in step), fill in meta/, and compile from this folder, since every path is relative to it:

lualatex beamer.tex
bibtex beamer
lualatex beamer.tex
lualatex beamer.tex

Use the theme in a deck you already have

Copy theme/ next to your .tex file and point LaTeX at it on the first line:

\makeatletter\def\input@path{{theme/}}\makeatother
\documentclass[aspectratio=1610]{beamer}
\usetheme{SimplePlusNord}

\title{Title}
\author{Name Surname}

\begin{document}
\begin{frame}
    \titlepage
\end{frame}

\begin{frame}{A slide}
    Some text.
\end{frame}
\end{document}

It is drawn for 16:10, so keep aspectratio=1610. Write \end{frame} alone on its line (see "Fragile frames" below). It works with pdfLaTeX, XeLaTeX and LuaLaTeX, tried on TeX Live 2023, and needs tcolorbox, listings, colortbl and booktabs, which TeX Live has. It uses \AddToHook, so very old LaTeX releases will not do.

Outline slides

Two options add an outline of the sections, one column each, on a dark slide:

• \usetheme[overview]{SimplePlusNord}: one right after the title slide.
• \usetheme[sectionslides]{SimplePlusNord}: one before every section, with the section that starts lit and the others faded.

A slide shows up in the outline only if a \subsection{Title} comes before it, because Beamer cannot read frame titles. To keep a slide out, write \subsection*{Title} or no \subsection at all (it then belongs to the entry before). \section* does the same for a whole section.

For the references, write \extrasection{References} instead of \section. It goes last in the outline, in blue, as a line under the columns, and no section slide opens it. The theme learns about it on the second run, so compile twice.

What you can write

• Boxes: infobox, alertbox and examplebox, each taking a title: \begin{infobox}{Title} ... \end{infobox}. Theorems, definitions and lemmas are boxes too, and a proof goes inside the box of its theorem. With a star (theorem*, definition*, and so on) the box is gone and the text is set as in an article.
• Tables: \headrule draws the line under the header, \hline the thin ones between rows.
• Sources: \source{Author (2021)} prints the source at the bottom left; several calls on a slide join into one line.
• Fading: \fade{text} lightens everything inside, your own colours included.
• Pictures: a PNG with a transparent background goes in with \includegraphics; an opaque photo with rounded corners with \roundedgraphics{file}.
• Dark slides: \darkslide, right after \begin{frame}, makes a slide dark and hides its title, since the body already says it.
• Outline by hand: \sectionlist is the sections as a bulleted list, good on a dark slide after the title. \sectioncolumns and \sectioncolumns[current] give the columns, plain or with the running section lit. \tocnumbers numbers the entries.
• Code: codeonly shows LaTeX code, codeblock{Python} any other language of listings (also C, C++, Julia, Pseudocode), numbered and with the language name faint at the top right. \code{mean(xs)} sets code inside a sentence, in the typewriter font scaled to the size of the text; \code[Python]{return sum(xs)} colours it too.
• Pseudocode: pseudocode uses the font of the deck, with bold keywords, <- as an arrow and $...$ for formulas. codeblock{Pseudocode} is the typewriter version.
• Fragile frames: every frame is read as fragile, so a code box works anywhere and you never write [fragile]. The price is that \end{frame} must stand alone on its line, and a bit more compile time. The option nofragile turns it off. Code inside the argument of \only or \uncover cannot work, as with any verbatim text: use \begin{onlyenv}<2> ... \end{onlyenv}.

Contrast

Body text is dark on light (10.8:1). Two things are weaker, about 3.5:1: the titles of the alert and example boxes, and the current page number. No other Nord colour carries light text any better. If you present in a bright room, try it there first.

Not checked yet: the look on a projector. \pause, \only, frame options such as [t] or [noframenumbering], and \appendix were tried in a small deck and work. The slides of the appendix count in the total of the page counter.

Credits

• It started from SimplePlus by Pin-Yen Huang. Most of the code has been rewritten since; thanks for the starting point. The name is different on purpose, so that TeX never loads the original by mistake.
• The palette is Nord, under the MIT licence.
• The two pictures are credited in slides/img/CREDITS.md.

Released under the Unlicense, see LICENSE.