@media (min-width: 768px) {
    h2
    {
        font-size: 32px;
        line-height: 32px;
    }
    #logo-header {
        width: 48px;
    }
    .header-about .element
    {
        display: block;
        height: 100%;
    }
    .header-about h3
    {
        width: 100%;
    }
    .btn.btn-default
    {
        font-size: 18px;
    }
    .contacts-block
    {
        font-size: 18px;
    }
    .contacts-block .btn
    {
        width: 220px;
    }
    footer {
        font-size: 18px;
    }
    #logo-footer
    {
        max-width: 64px;
    }
    nav a.nav-link:after
    {
        margin: 0 auto;
    }
    nav a.nav-link:hover:after,
    nav .navbar-nav .nav-link.active:after
    {
        width: 80%;
    }
}
@media (min-width: 992px) {
    h2
    {
        font-size: 48px;
        line-height: 48px;
    }
    #logo-header {
        width: 64px;
    }
    nav .nav-link
    {
        font-size: 20px;
        line-height: 20px;
        margin-left: 4em;
    }
    .header-about .element
    {
        border: none;
    }
    .btn.btn-default
    {
        font-size: 21px;
    }
    .btn.btn-secondary
    {
        font-size: 30px;
    }
    .contacts-block
    {
        font-size: 21px;
    }
    footer {
        font-size: 18px;
    }
    #logo-footer
    {
        max-width: 81px;
    }
}
@media (min-width: 1200px) {
    h2
    {
        font-size: 70px;
        line-height: 70px;
    }
    .container, .container-lg, .container-md, .container-sm, .container-xl {
        max-width: 1560px;
    }
    #logo-header {
        width: 84px;
    }
    .header-about h3
    {
        font-size: 82px;
        font-weight: 600;
        line-height: 82px;
    }
    .header-about p
    {
        font-size: 24px;
        line-height: 24px;
    }
    .btn.btn-default
    {
        font-size: 30px;
    }
    .contacts-block
    {
        font-size: 30px;
    }
    .contacts-block .btn
    {
        width: 368px;
        font-size: 30px;
    }
    .contacts-block img
    {
        width: 70px;
    }
    footer {
        font-size: 30px;
    }
    #logo-footer
    {
        max-width: 154px;
    }
    .contacts-block iframe
    {
        border-radius: 20px;
    }
}
@media (min-width: 1400px) {
    .header-about h3
    {
        font-size: 110px;
        font-weight: 600;
        line-height: 110px;
    }
    .header-about p
    {
        font-size: 30px;
        line-height: 30px;
    }
}