reveal.js is an open source HTML presentation framework. the most important keys are the dot, B, F and esc. control your presentation also by your smartphone (needs the app remote Mouse both in Desktop/Laptop and mobile device).
By default the slides are stepped between using a horizontal sliding transition. It's also possible to nest multiple slides within a single top-level slide to create a vertical stack. See the arrows right down.
Content can disappear...
...or become red
...and appear again
add the code: center:false, below Reveal.initialize({ (see the source) if you want the elements begins top left.
Change styles with CSS. For example: with CSS masking you create a mask layer to place over an element to partially or fully hide portions of the element. Some browsers only have partial support for CSS masking. You will need to use the -webkit- prefix in addition to the standard property in that browsers. → reload this page if the video doesn't play anymore.
Do you remember the most important keys dot, B, F and esc?
FINE