text: /**
   * Check if an element has a class
   * @param {HTMLElement} elm
   * @param {string} cls
   * @returns {boolean}
   */
  export function hasClass(ele, cls) {
    return !!ele.className.match(new RegExp("(\\s|^)" + cls + "(\\s|$)"));
  }
  
  /**
   * Add class to element
   * @param {HTMLElement} elm
   * @param {string} cls
   */
  export function addClass(ele, cls) {
    if (!hasClass(ele, cls)) ele.className += " " + cls;
  }
  
  /**
   * Remove class from element
   * @param {HTMLElement} elm
   * @param {string} cls
   */
  export function removeClass(ele, cls) {
    if (hasClass(ele, cls)) {
      const reg = new RegExp("(\\s|^)" + cls + "(\\s|$)");
      ele.className = ele.className.replace(reg, " ");
    }
  }
  