.header {
    width: 100%;

    position: fixed;
    top: 0;
    left: 0;

    display: flex;
    justify-content: space-between;
    align-items: center;

    padding: 1.8rem 6rem;
    box-sizing: border-box;

    background-color: transparent;

    transition: var(--tr-quick);
    z-index: 1000;
}

.header.hidden {
    transform: translateY(-100%);
}
.header.blended {
    mix-blend-mode: difference;
}

.header__nav a, .header__nav span {
    font-weight: 400;
    color: var(--clr-white);
}

.header__menu, .header__menu-item, .header__submenu, .header__submenu-item {
    margin: 0;
    padding: 0;
}

.header__menu {
    display: flex;
    margin: 0 -2.3rem;
}

.header__menu-item, .header__submenu-item {
    list-style: none;
}

.header__menu-item {
    position: relative;

    padding: 0 2.3rem;

    font-size: 1.5rem;
    line-height: 2.1rem;
    font-weight: 500;
    text-transform: uppercase;
}

.header__submenu {
    max-height: 0;
    overflow: hidden;

    position: absolute;
    bottom: 0;
    transform: translateY(90%);

    padding-top: .8rem;

    opacity: 0;
    z-index: -1;
    transition: var(--tr-quick);
}

.header__menu-item:hover > .header__submenu {
    max-height: none;
    overflow: unset;

    display: block;

    opacity: 1;
    z-index: 10;

    transform: translateY(100%);
}

.header__submenu-item {
    margin-top: .4rem;

    font-size: 1.3rem;
    line-height: 2.1rem;
    font-weight: 400;
    text-transform: uppercase;
    white-space: nowrap;
}

.header__nav--desktop {
    display: block;
}
.header__nav--mobile {
    display: none;
}

.burger-btn {
    width: 2.4rem;
    height: 1.7rem;

    display: none;
    flex-direction: column;
    justify-content: space-between;

    position: absolute;
    left: 1.6rem;
    top: 50%;
    transform: translateY(-50%);
}

.burger-btn__item {
    width: 100%;
    height: 1px;
    display: block;
    background: var(--clr-black);

    border-radius: 4px;

    transition: var(--tr-quick);
}

.header.open-menu .burger-btn__item:nth-child(1) {
    transform: translateY(0.75rem) rotateZ(45deg);
}
.header.open-menu .burger-btn__item:nth-child(3) {
    transform: translateY(-0.8rem) rotateZ(-45deg);
}
.header.open-menu .burger-btn__item:nth-child(2) {
    opacity: 0;
}

.hidden-menu {
    width: 100%;
    max-height: 0;
    overflow: hidden;

    position: absolute;
    top: 8rem;
    left: 0;

    display: none;
    transform: translateY(-1%);

    background: var(--clr-white);
    color: var(--clr-black);
    transition: var(--tr-quick);
}

.hidden-menu__item {
    width: 100%;
    height: 4.8rem;

    display: flex;
    justify-content: space-between;
    align-items: center;

    padding: 1rem 3.1rem;
    box-sizing: border-box;

    border-top: 1px solid #CBCAD1;
    font-size: var(--fz-text);
    font-weight: 500;
    color: var(--clr-black);
}

.hidden-menu__caret {
    transition: var(--tr-quick);
}

.hidden-menu__group {}

.hidden-menu__item--group-btn.open .hidden-menu__caret {
    transform: rotate(180deg);
}

.hidden-menu__item--group-btn.open + .hidden-menu__group-list{
    max-height: unset;
    overflow: unset;
    padding: 1.9rem 0;
    border-color: #CBCAD1;
}

.hidden-menu__group-list {
    max-height: 0;
    overflow: hidden;
    border-top: 1px solid transparent;
    transition: var(--tr-quick);
}

.hidden-menu__group-list a {
    display: block;
    padding: 1.1rem 4.7rem;
    color: var(--clr-black);
}

.hidden-menu__item--black {
    background: var(--clr-black);
    color: var(--clr-white);
}

.header.open-menu .hidden-menu {
    max-height: unset;
    overflow: unset;
    transform: translateY(0);
}

@media screen and (max-width: 960px) {
    .header {
        height: 8rem;
        background: var(--clr-white);
    }
    .header.blended {
        mix-blend-mode: normal;
    }
    .header__logo {
        position: absolute;
        top: 50%;
        left: 50%;
        transform: translate(-50%, -50%);
        mix-blend-mode: difference;
    }
    .header__logo svg {
        width: 8rem;
        height: 8rem;
    }
    .header__nav {
        display: none;
    }
    .hidden-menu {
        display: block;
    }
    .burger-btn {
        display: flex;

        width: 2.4rem;
        height: 1.7rem;
    }
}

@media screen and (max-width: 450px) {
    .header {
        height: 4.2rem;
    }
    .header__logo svg {
        width: 5.4rem;
        height: 3.37rem;
    }
    .burger-btn {
        width: 1.6rem;
        height: 1.1rem;
    }
    .header.open-menu .burger-btn__item:nth-child(1) {
        transform: translateY(0.5rem) rotateZ(45deg);
    }
    .header.open-menu .burger-btn__item:nth-child(3) {
        transform: translateY(-0.5rem) rotateZ(-45deg);
    }
    .hidden-menu {
        top: 4.2rem;
    }
}

.callback {
    min-height: 72rem;
    height: 100%;

    display: flex;
    flex-direction: column;
    justify-content: center;
}

.callback__title {
    font-family: var(--ff-Acta);
    font-size: 9rem;
    line-height: 1;
}
.callback__title span {
    display: block;
    color: var(--clr-blue);
}
.callback__subtitle {
    display: block;
    margin-top: 4.2rem;
}
.callback__form {
    margin-top: 4.4rem;
}

.callback__form .row {
    --row-margin: -1.2rem;
    --col-padding: 1.2rem;

    align-items: flex-end;
}
.callback__form .btn-black {
    width: 100%;
    margin-top: 2rem;
}

@media screen and (max-width: 960px) {
    .callback {
        padding: 4.8rem 0;
    }
    .callback__subtitle {
        text-align: left;
        padding-bottom: 6rem;
    }
}

@media screen and (max-width: 510px) {
    .callback__title {
        font-size: 16vw;
    }
}

.footer {
    position: relative;

    padding: 10rem 0;

    background: var(--clr-black);
    color: var(--clr-white);
    font-size: 1.5rem;
}
.footer__section-title {
    margin-bottom: 2.4rem;
    font-weight: 700;
}
.footer__links-group {}
.footer__link{
    display: block;
    color: inherit;
    line-height: 2.1rem;
    transition: var(--tr-quick);
}
.footer a:hover {
    opacity: .5;
}
.footer__social-group {
    max-width: 27rem;
    width: 100%;

    display: flex;
    align-items: center;
    justify-content: flex-start;

    margin: 2.8rem -1rem 0;
}
.footer__social {
    padding: 0 1rem;
    transition: var(--tr-quick);
}
.footer__creds {
    display: block;
    margin-top: 6.7rem;
    font-size: 1.2rem;
    color: #717275;
}