Get, set, and remove a CSS variable in JavaScript

css-vars.js

function getCSSVar(name, element = document.documentElement) {
    return getComputedStyle(element).getPropertyValue(`--${name}`);
}

function setCSSVar(name, value, element = document.documentElement) {
    element.style.setProperty(`--${name}`, value);
}

function removeCSSVar(name, element = document.documentElement) {
    element.style.removeProperty(`--${name}`);
}

great works!