header {
    background-color: #fff;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.nav-menu {
    display: flex;
}

.nav-menu li {
    margin-left: 2rem;
}

.nav-menu a {
    color: var(--color-dark);
    font-weight: 600;
}

.nav-menu a:hover {
    color: var(--color-primary);
}