Backport formatting from Julia course (2022-06-08)

See merge request !20

ref here: https://github.com/SebastianAigner/twemoji-amazing

Normally you'd do this with unicode in browser, but browser rendering of the
pictures is far from optimal and I don't see much improvement possible.
Maybe a good emoji font eventually appears that works in chrome.

avoid centering of text when the slides are zoomed out

See merge request !19

When pressing [esc], the text on the tiny slides appears centered, because of
a rule

```
.reveal .slides {
  text-align: center;
}
```

that is inherited from Reveal.js default theme. In turn, the slide thumbnails
look completely different from what's actually displayed. This is the minimal
css change that fixes it for me. Not necessarily ideal, but I probably lack the
high-level view to judge. :]

change position of placeholder

See merge request !18

add matomo hook

See merge request !17

Addding content box and profile box to css

See merge request !16

Vilem Ded authored Mar 09, 2020 and Laurent Heirendt committed Mar 09, 2020

This reverts commit b7b075cd.

Regular merge of develop

See merge request !15

fix https

See merge request !14

Regular merge of develop

See merge request !13

add math to template

See merge request !12

Regular merge of develop

See merge request !11

Change code style

See merge request !10

fix code overlap

See merge request !9

Regular merge of develop

See merge request !8

Minor changes

See merge request !7

Regular merge of develop

See merge request !6

Make presentation theme mobile ready

See merge request !5