.site-header,
header {
    width: 100%;
    transition: all 0.3s ease;
}

.smb-sticky {
    position: fixed;
    top: 0;
    left: 0;
    z-index: 9999;
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}