header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 18px 80px;
    background: rgba(5,10,30,0.9);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 50;
    backdrop-filter: blur(12px);
}

header img {
    height: 48px;
}

/* Desktop Nav */
.nav-menu {
    display: flex;
}

.nav-menu a {
    margin-left: 32px;
    text-decoration: none;
    color: var(--text-muted);
    font-weight: 500;
    transition: 0.3s;
}

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

/* Hamburger Button */
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 6px;
    cursor: pointer;
}

.menu-toggle span {
    width: 26px;
    height: 2px;
    background: var(--blue-light);
    border-radius: 2px;
    transition: 0.3s;
}

/* Mobile Menu Panel */
.mobile-nav {
    position: fixed;
    top: 70px;
    right: 20px;
    background: linear-gradient(180deg, #0b1f4b, #07122f);
    border: 1px solid rgba(26,163,255,0.4);
    border-radius: 10px;
    padding: 15px 25px;
    display: none;
    flex-direction: column;
    gap: 15px;
    z-index: 40;
    box-shadow: 0 0 25px rgba(26,163,255,0.3);
}

.mobile-nav a {
    text-decoration: none;
    color: var(--text-light);
    font-weight: 500;
}

/* ===== Responsive ===== */
@media(max-width: 900px) {
    .nav-menu {
        display: none;
    }
    .menu-toggle {
        display: flex;
    }
}

/* Active menu state */
.nav-menu a.active,
.mobile-nav a.active {
    color: var(--blue-light);
    position: relative;
}

.nav-menu a.active::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: -6px;
    width: 100%;
    height: 2px;
    background: var(--blue-light);
    border-radius: 2px;
    box-shadow: 0 0 8px rgba(26,163,255,0.8);
}