getStyleValue

Untitled-1

/**
 * 
 * @param el Element
 * @param CSS property in hyphen case 
 * @param pseudo pseudo selector (optional)
 */
function getStyleValue(el, property, pseudo) {
    // convert hyphen-case to camelCase
    const elStyle = el.style[property.replace(/(\-[a-z])/g, $1 =>  $1.toUpperCase().replace('-',''))];
    return ((elStyle !== '' && !pseudo) 
        ? elStyle
        : window.getComputedStyle(el, pseudo).getPropertyValue(property));
}