(function() {

    'use strict';

    var section = document.getElementsByTagName('section')[0];
    var sectionInitialColor = window.getComputedStyle(section, null).getPropertyValue('background-color');
    var timer;
    var interval;
    var currentTime = 0;
    var time = 10000;
    var elapsedTime = 0;
    var childh = section.getElementsByTagName('h2');
    var p;

    section.addEventListener('click', function(e) {
        section.style.backgroundColor = 'DarkViolet';
        currentTime = currentTime - elapsedTime + time;
        clearTimeout(timer);
        clearInterval(interval);
        elapsedTime = 0;
        timer = setTimeout(function() {
            if(section.style.backgroundColor === sectionInitialColor) {
                currentTime = 0;
            } else {
                currentTime -= time;
            }
            section.style.backgroundColor = sectionInitialColor;
        }, currentTime);
        interval = setInterval(function() {
            elapsedTime += 1000;
        }, 1000);
    });

    for(let i = 0; i < childh.length; i++) {
        childh[i].addEventListener('click', function(e) {
            p = document.createElement('p');
            p.textContent = childh[i].textContent;
            section.appendChild(p);
            e.stopPropagation();
        });
    }

})();