Indeed, the example in the wiki is outdated. The priorities of CSS classes, default CSS styles and JSXGraph are a little bit delicate.Please, have a look at the API docs: https://jsxgraph.org/docs/symbols/Text.html#cssDefaultStyle.
If you want to overwrite font-family, you have to set cssDefaultStyle
to the empty string:
JXG.Options.text.cssDefaultStyle = '';
JXG.Options.text.highlightCssDefaultStyle = '';
const board = JXG.JSXGraph.initBoard('jxgbox', {
boundingbox: [-1,15,15,-1],
showcopyright: false,
axis: true,
// ...
});
var txt = board.create('text', [3,4,
" <span id='par'>(</span> Hello world <span id='par'>)</span>"
], {
cssClass:'myFont',
highlightCssClass: 'myFont',
strokeColor: 'red',
highlightStrokeColor: 'blue',
fontSize:20
});
See it live at https://jsfiddle.net/2jq8srpv/3/
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