export function hasClass(node, className) { if (node.classList) { return node.classList.contains(className); } const originClass = node.className; return ` ${originClass} `.indexOf(` ${className} `) > -1; } export function addClass(node, className) { if (node.classList) { node.classList.add(className); } else { if (!hasClass(node, className)) { node.className = `${node.className} ${className}`; } } } export function removeClass(node, className) { if (node.classList) { node.classList.remove(className); } else { if (hasClass(node, className)) { const originClass = node.className; node.className = ` ${originClass} `.replace(` ${className} `, ' '); } } }