system de variable dans css code example
Example: javascript use css custom properties
Values in JavaScript
To use the values of custom properties in JavaScript, it is just like standard properties.
// get variable from inline style
element.style.getPropertyValue("--my-var");
// get variable from wherever
getComputedStyle(element).getPropertyValue("--my-var");
// set variable on inline style
element.style.setProperty("--my-var", jsVar + 4);