function becomingBigger() {
    if(switchOfAnimation) {
        footer.firstElementChild.style.cssText = "-webkit-transform:scale(1.5);\
                                                  -moz-transform:scale(1.5);\
                                                  -ms-transform:scale(1.5);\
                                                  -o-transform:scale(1.5);\
                                                  transform:scale(1.5);";
        setTimeout(becomingSmaller, 21000);
    } else return;
}

function becomingSmaller() {
    if(switchOfAnimation) {
        footer.firstElementChild.style.cssText = "-webkit-transform:scale(1);\
                                                  -moz-transform:scale(1);\
                                                  -ms-transform:scale(1);\
                                                  -o-transform:scale(1);\
                                                  transform:scale(1);";
        setTimeout(becomingBigger, 21000);
    } else return;
}

//Анимируем header & main part of article & footer of article
function animation() {

    //Header
    if(!headerFlag && Math.abs(header.getBoundingClientRect().top / window.innerHeight) < 0.2) {
        header.firstElementChild.nextElementSibling.firstElementChild.lastElementChild.style.cssText = "-webkit-transform: translateX(101%);\
                                                                                                        -moz-transform: translateX(101%);\
                                                                                                        -ms-transform: translateX(101%);\
                                                                                                        -o-transform: translateX(101%);\
                                                                                                        transform: translateX(101%);";
        header.firstElementChild.nextElementSibling.firstElementChild.firstElementChild.style.opacity = "1";
        header.firstElementChild.nextElementSibling.lastElementChild.style.cssText = "opacity: 1;\
                                                                                      -webkit-transform: translateY(0);\
                                                                                      -moz-transform: translateY(0);\
                                                                                      -ms-transform: translateY(0);\
                                                                                      -o-transform: translateY(0);\
                                                                                      transform: translateY(0);";
        headerFlag = true;
    }

    //Main part of article
    if(!aboutUsFlag) {
        aboutUsFlag = true;
    }

    //Footer of article
    if(!footerFlag && footer.getBoundingClientRect().top / window.innerHeight < 0.6 && footer.getBoundingClientRect().top >= 0) {
        footer.firstElementChild.nextElementSibling.lastElementChild.style.cssText = "-webkit-transform: translateX(101%);\
                                                                                      -moz-transform: translateX(101%);\
                                                                                      -ms-transform: translateX(101%);\
                                                                                      -o-transform: translateX(101%);\
                                                                                      transform: translateX(101%);";
        footer.firstElementChild.nextElementSibling.firstElementChild.style.opacity = "1";
        footer.lastElementChild.style.cssText = "opacity: 1;\
                                                 -webkit-transform: translateY(0);\
                                                 -moz-transform: translateY(0);\
                                                 -ms-transform: translateY(0);\
                                                 -o-transform: translateY(0);\
                                                 transform: translateY(0);";
        footerFlag = true;
    }

    if(!switchOfAnimation && footer.getBoundingClientRect().top / window.innerHeight < 0.6 && footer.getBoundingClientRect().top >= 0) {
        switchOfAnimation = true;
        becomingBigger();
    } else if((switchOfAnimation && footer.getBoundingClientRect().top / window.innerHeight > 0.6) || footer.getBoundingClientRect().top < 0) {
        switchOfAnimation = false;
        footer.firstElementChild.style.cssText = "-webkit-transform:scale(1);\
                                                  -moz-transform:scale(1);\
                                                  -ms-transform:scale(1);\
                                                  -o-transform:scale(1);\
                                                  transform:scale(1);";
    }
}