.burger {
    display: none;
}

.call-btn {
    display: none;
}

@media all and (max-width: 768px) {

    .call-btn {
        display: flex;
        justify-content: center;
        align-items: center;
        position: fixed;
        left: 20px;
        bottom: 20px;
        width: 56px;
        height: 56px;
        border-radius: 50%;
        border: 1px solid rgba(0, 0, 0, .2);
        background: #fff;
        box-shadow: 0 0 16px 4px rgba(255, 255, 255, .8);
        z-index: 25;
    }

    .call-btn img {
        width: 26px;
        height: 26px;
    }

    header {
        position: sticky;
        top: 0;
        width: 100%;
        height: 64px;
        line-height: 64px;
        background: white;
        z-index: 15;
        display: flex;
        align-items: center;
    }

    .burger {
        display: flex;
        flex-direction: column;
        justify-content: center;
        gap: 5px;
        width: 32px;
        height: 32px;
        padding: 0;
        background: none;
        border: none;
        cursor: pointer;
        z-index: 20;
    }

    .burger span {
        display: block;
        width: 100%;
        height: 2px;
        background: black;
        transition: transform .25s ease, opacity .25s ease;
    }

    .burger.active span:nth-child(1) {
        transform: translateY(7px) rotate(45deg);
    }

    .burger.active span:nth-child(2) {
        opacity: 0;
    }

    .burger.active span:nth-child(3) {
        transform: translateY(-7px) rotate(-45deg);
    }

    .header__nav {
        position: fixed;
        top: 64px;
        left: 0;
        width: 100%;
        flex-direction: column;
        align-items: center;
        gap: 18px;
        background: white;
        padding: 24px 0;
        box-shadow: 0 6px 4px -4px rgba(0, 0, 0, .2);
        opacity: 0;
        transform: translateY(-10px);
        pointer-events: none;
        transition: opacity .25s ease, transform .25s ease;
        z-index: 15;
    }

    .header__nav.active {
        opacity: 1;
        transform: translateY(0);
        pointer-events: auto;
    }

    .header__nav-item {
        font-size: 16px;
    }
}

@media all and (max-width: 440px) {

    .header__logo img {
        max-height: 40px;
    }
}