javascript set css property variable code example
Example 1: javascript get css variable
let docStyle = getComputedStyle(document.documentElement);
//get variable
let myVarVal docStyle.getPropertyValue('--my-variable-name');
//set variable
docStyle.setProperty('--my-variable-name', '#fff');
Example 2: how to change css variable in javascript
document.documentElement.style.cssText = "--main-background-color: red";