proper way to update widget style (such as font-size) ?

Hello, I’ve noticed that since version 5.0 it is not possible to set style parameters such as ‘font-size’ with the following syntax

from ipywidgets import widgets
w=widgets.Text("example",font_size=75)
display(w)

neither this way:

from ipywidgets import widgets
w=widgets.Text("example")
w.font_size=75
display(w)

What is the proper way? I’ve found anything in the doc 😦

[sjdv1982]

@meyermj, @patrickhoebeke : I had the same problem. After studying what CSS is and how it works, I managed a hack:

import ipywidgets
w = ipywidgets.Text("test", description="Title")
w.add_class("mytext")
w

%%html
<style>
.mytext > .widget-label {
    font-style: italic;
    color: blue;
    font-size: 30px;
}
.mytext > input[type="text"] {
    font-size: 20px;
    color: red;
}
</style>

Note that %%html is simply a wrapper around IPython.display.display_html. So it would be possible to create some kind of Pythonic (kernel-side) front-end that generates and displays the CSS. At the very least, one could use something less awkward than pure CSS (it appears that there are dialects with improved syntax, like SASS, which are pre-processed/compiled into CSS).

But, in addition, one could inform a smart (kernel-side) front-end about the internal DOM structure of the ipywidget.To my taste, this is a more flexible way to allow styling than the current method of exposing arbitrary attributes to the model-view-comm framework. But I am not really qualified to judge, since I know nothing about (browser-side) front-end development.

[djleach-belcan]

It does not seem possible to modify the font size or color of a Label or Text widget. How should this be accomplished?