Somehow, I don't see the mention of the Vega visualization grammar [1] as a potential charting library. I think it is incredibly well-done, and is generally intuitive in its API. I've mostly used it through the Python bindings called Altair [2]. The good part is that that general grammar carries over to the browser as a full JSON spec that can be used directly in any language that supports JSON and has a Vega binding (which is pretty much all popular languages).
Having said that, I had to unfortunately abandon it because the ad-hoc control with Matplotlib [3] in Python is just infectious. Visual manipulations are far less easy to do in Vega. Being in JSON is also a restrictive though, because it is less interpretable by unstructured bots, where charts.css probably excels by design.
I think I just stopped my train of thought and hit reply.
I meant to point out that Charts.css relies on having <table> elements in the HTML. Vega relies purely on JSON. This may or may not be of concern. For instance, if you care about bots crawling the website for semantic information, then perhaps the Charts.css way of operating on top of <table>s is preferred. A minor point though.
oh wow, i really should look into vega now.. i too know little about web technologies and benig handed task to create beautiful graphs in very short period of time... :sigh
Having said that, I had to unfortunately abandon it because the ad-hoc control with Matplotlib [3] in Python is just infectious. Visual manipulations are far less easy to do in Vega. Being in JSON is also a restrictive though, because it is less interpretable by unstructured bots, where charts.css probably excels by design.
[1]: https://vega.github.io [2]: https://altair-viz.github.io [3]: https://matplotlib.org