Cards - A really simple deck of cards

Instructions: make a HTML file containing
- a <div id="canvas"> and styles for it
- a <div id="cards"> containing the cards as individual elements
- styles for the cards.
- include this script

This will display all cards or the selected card, fitted into the
#canvas. Click/touch a card to select it or to return to the
selection.

Cards are scaled to fit the screen size by adjusting the font
size. Therefore, styles for cards should be relative to the font
size (=specified in em); pixel dimensions will not work. Cards
will be placed within a container that has class "card-container".
In addition, the container will have "card-selection" or
"card-current", depending on whether all cards or just the current
card are shown.

(c) 2017 Stefan Reuther <streu@gmx.de>