This is a template for slides using the Shower JavaScript framework with a W3C style. For usage instructions, see at the end.

To start the slide show, turn on JavaScript and click on a slide. Return to the index by pressing the Esc key.

The W3C slide style

… for the Shower framework

Bert Bos


An example of a numbered list:

  1. Potatoes
  2. Onions and olives

An example of an unordered list:

Some elements

Words can be given a strong emphasis, which makes them appear in bold

The normal emphasis has a highlighter effect.

Code looks like this: if (a) return b;

This is an example of a note, in a smaller font

Incremental display

An image on the side

[Picture of a stylized tree with colorful, square leaves]

It seems the famous ‘lorem ipsum’ is based on a text by Cicero, but with the lines mixed up. On a Cicero by the text, it seems the ‘ipsum lorem’ is famous based with lines but mixed up.

An image on the side

[Picture of a stylized tree with colorful, square

And again, with class ‘slide side right’.

It seems the famous ‘lorem ipsum’ is based on a text by Cicero, but with the lines mixed up. On a Cicero by the text, it seems the ‘ipsum lorem’ is famous based with lines but mixed up.

In columns

Children of an element with a class of ‘columns’ are distributed over two columns

This is the second child, which goes into the right column

And this is the third one. Left column again.


place t l
place t
place t r
Here is something for the left side, with class place l
class place puts an element centered in a 3×3 grid
place r
place b l
place b
combine place with top (or t), right (or r), bottom (or b) and left (or l)

Numbered lines of code

Lines in a PRE can be numbered
  * Give the PRE a class of "numbered"
  * Works for up to 20 lines
                       (depending on font size)

Image overlay: cover

A bridge over the Rhone in Lyon

Careful, some images make the text hard to read!

Image overlay: fit

A bridge over the Rhone in Lyon

Careful, some images make the text hard to read!

Shout and grow!


Takahashi method!

Shout & Grow:


Grow: Don't use this too often!

Slide transitions

The style sheet predefines several transitions: fade-in, slide-in, move-left, etc.

A transition can be set globally, applying to all slides; and locally, applying only to the transition between this slide and the next.

Thank you!


Setting up your slides

This is a template for slides using the Shower framework (version 2.1.0) with a W3C style. The Shower JavaScript code manages the slide progression, while the style sheet provides the W3C look and some useful predefined layout styles.

If you write slides with this style, you can either put them online or download a zip with everything needed to present offline, as explained below.

Note: The same slides and the same style can also be used with the b6+ framework. Look in the HTML source for how to change the script.

Developing slides online

If you develop your slides online (or in CVS), then make a directory under or (or whatever the current year is). The former will be public, the latter requires setting an ACL. Copy shower2.html (this file) from into your directory and edit the content, or just use it as an example.

Developing slides offline

If you develop your slides offline (or plan to present them without a network), then download this zip file. Unpacking it creates the following directories and files:

Make a directory for your own slides under slides. (A good name is MMDD-Theme, where MM is the month in which you give the talk, DD the date and Theme the topic, e.g., ‘Legal’, ‘W3C’ or ‘SVG’.) You can copy the shower2.html file there as a starting point, or just use it as an example. If you make any images, put them in that directory as well.

If you are able to upload your slides, put your directory with all that it contains under or (replace 2019 by the current year). There is no need to upload the Tools directory. It is is already there.

Writing slides


Each slide is a div element* with a class of slide:

<div class="slide">
  ... slide content here...

Inside the slides, use normal HTML elements (p, ul, em, etc.).

*) Note for advanced users: Although not shown in this template, it is in fact possible to use other elements than div. One common choice is section.

Slide numbers

If a slide should not show the slide number, add the class clear:

<div class="slide clear">
  ... slide content here...

Title slides (cover slides)

For cover slides (the title slide or separator slides between parts of a presentation), add a class cover. You can combine cover and clear. E.g.:

<div class="slide cover clear">
  <h1>My presentations<h1>
  <address>Peter W. Slidemaker</address>

Illustrations on the left or right

Slides with narrower text and an illustration on the left can be made by adding the class side to the slide. Inside the slide there should be exactly one element that also has a class of side (an image or some other element):

<div class="slide side">
  <img src="..." alt="..." class="side">
  ... slide content here...

The side element will occupy the left 1/3 of the slide and the rest of the content the right 2/3.

To put the image on the right instead, add class right (which may be abbreviated to r):

<div class="slide side r">
  <img src="..." alt="..." class="side">
  ... slide content here...

Automatic slide shows

Slides can be made to advance automatically after a given time, by setting a data-timing attribute on them with a value of MM:SS (minutes and seconds). E.g.,

<div class="slide" data-timing="1:03">

This slide will remain on screen no longer than 1 minute and 3 seconds, after which the next slide will be shown.

Progress bar

If you want a progress bar during the slide presentation, add an empty div with a class of progress. It can be put before the first slide or after the last, but there should be at most one such element in the file:

<div class="progress"></div>

The progress bar will show as a thin red line along the top of the slides. Its length increases from zero on the first slide to 100% on the last.

Incremental display

To progressively reveal elements on a slide, put a class of next on all elements that should not be visible right away. They will become visible one by one as you press the space bar or an arrow key. E.g.:

  <li>This item is visible when the slide appears</li>
  <li class="next">This item is not immediately visible</li>
  <li class="next">This is the third item to appear</li>
<p class="next">This is the last element to appear</p>

Note: Incremental display only works with online slides. When presenting slides from your local disk, elements with class=next will not show. (This is due to the way Shower remembers state, which triggers a security exception.) If you need incremental display, you might be able to use b6+ instead.

Two columns

To put elements side by side in two columns, make an element (a div, ul or any other element) with class columns. The first child of that element will be put in the left column, the second child in the right column. If there are more children, the third will be in the left column again, the fourth in the right, etc.

<ul class="columns">
  <li>First goes on the left</li>
  <li>Second goes on the right</li>

Small text

Less important text can be shown in a smaller font by giving it a class of note:

<p class="note">Note that this is harder to read</p>

Automatic line numbering

Pre-formatted text (in a pre) can be given line numbers by adding the class numbered:

<pre class="numbered">

No more than 20 lines will be numbered. (In the normal font size, a slide fits 13 lines.)

3×3 Grid

It is possible to treat the slide as a 3×3 grid and put elements in the four corners, in the middle of each edge, or in the center of the slide. This is done by giving the elements a class of place. On its own, place puts the element in the center. By adding classes top, right, bottom and left the element can be placed in one of the eight other positions.

<div class="place">Put this in the center</div>
<div class="place bottom">Put this bottom center</div>
<div class="place top right">In the top right corner</div>

The direction classes can also be abbreviated to t, r, b and l.

Image overlays (background images)

To put an image behind the text of a slide, use an img with a class of cover:

<img class="cover" src="..." alt="...">

The image will be stretched to fill the whole of the text area. If the image doesn't fit exactly (wrong aspect ratio), the image will be cropped.

With a class of fit instead of cover, the image will be scaled but without cropping. Instead there may be white bands on the sides or above/below the image, if it doesn't fit exactly.

<img class="fit" src="..." alt="...">

This works both for normal slides and title slides (slides with a class of cover). The logo on the right is not obscured by the image.

Slide transitions

By default, each slide just replaces the previous one, but there are several predefined slide transitions. You can set a transition on the body element to apply it to all slides:

<body class="shower fade-in">

Or you can set it on individual slides, to apply only to the transition between that slide and the next. (I.e., it doesn't determine how the slide appears, but how it disappears.)

<div class="slide wipe-left">

You can set both a global transition and local ones. The global transition applies to slides that do not have an explicit transition set locally.

The new slide appears faint at first and gets more opaque until it completely obscures the previous slide.
The new slide moves in from the left, while the previous slide moves back to the left.
The new slides move in from the right while the old slide moves out to the left.
The old slide moves up and the new slide moves in from the bottom.
A 3D effect: the bottom of the old slide is lifted up and the slide is turned over to reveal the new slide on its back side.
Another 3D effect, but in this case the right side of the slide is lifted up and the slide is flipped over to the left, revealing the new slide on the back side.
A small circle appears in the middle of the old slide that reveals the new slide. The circle grows until it covers the whole slide.
The new slide moves in from the right, until it covers the old slide.
A zigzag pattern moves in from the right. To the left is the old slide, to the right the new one.
A zigzag pattern moves in from the left. To the left is the new slide, to the right the old one.
The new slide moves in from the top left and covers the old slide.


To present the slides, load them into a browser that supports JavaScript and CSS and then click on the first slide.

Navigate though the slides by pressing the space bar, the arrow keys or Page-up/Page-Down. The Home and End keys jump to the first, resp. last slide.

To exit the presentation, press the Esc key.

The complete list of key strokes is in the Shower documentation.

Created 4 March 2019 by Bert Bos. Last modified $Date: 2020/09/11 20:09:31 $ by $Author: bbos $.