.header--fixed {
    position: relative;
    top: 0;
    opacity: 1;
    z-index: 999;
    left: 50%;
    transform: translateX(-50%);
    transition: all .3s linear;
    width: 100%;
}
.header__hide {
    opacity: 0;
    position: fixed;
    transform: translate(-50%, -100%);
}
.is-show {
    position: fixed;
    top: 0px;
    opacity: 1;
    z-index: 999;
    transition: all .3s linear;
}

@media (max-width: 767px) {
    .header__hide {
        opacity: 1;
        position: relative;
    }
    .log {
        display: none;
    }
}