.stm-header__row_color.pearl_is_sticky {
    transition: .3s ease;
}

.stm-header__row_color.pearl_going_sticky {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    transform: translateY(-100%);
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.05);
    transition: 0s ease;
}

.stm-header__row_color.pearl_sticked {
    transform: translateY(0);
    transition: .3s ease;
}