.navbar {
    position: fixed; top: 0; left: 0; right: 0; z-index: 100;
    padding: 0 24px; padding-top: max(0px, env(safe-area-inset-top)); height: 64px;
    display: flex; align-items: center; justify-content: space-between;
    background: rgba(255,255,255,0.88);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border-bottom: 1px solid rgba(0,0,0,0.06);
    transition: all 0.3s cubic-bezier(0.4,0,0.2,1);
}
.navbar.scrolled { box-shadow: 0 4px 20px rgba(0,0,0,0.06); }
.nav-brand a {
    font-size: 1.25rem; font-weight: 800; color: #4f6ef7;
    text-decoration: none; display: flex; align-items: center;
    gap: 10px; letter-spacing: -0.5px;
}
.nav-brand a:hover { color: #3a56d4; }
.nav-brand img { height: 34px; border-radius: 8px; }
.nav-links { display: flex; gap: 4px; align-items: center; }
.nav-links a {
    padding: 8px 16px; text-decoration: none; color: #5a6a7e;
    font-size: 14px; font-weight: 500; border-radius: 24px;
    transition: all 0.3s;
}
.nav-links a.active {
    background: #4f6ef7; color: white;
    box-shadow: 0 8px 24px rgba(79,110,247,0.2);
}
.nav-links a:hover { background: rgba(79,110,247,0.08); color: #4f6ef7; }
.nav-links a.active:hover { background: #3a56d4; }
.nav-right { display: flex; align-items: center; gap: 8px; }
.dark-toggle {
    width: 36px; height: 36px; border-radius: 50%; border: none;
    background: rgba(0,0,0,0.04); cursor: pointer; font-size: 16px;
    display: flex; align-items: center; justify-content: center;
    transition: all 0.3s;
}
.dark-toggle:hover { background: rgba(0,0,0,0.08); transform: rotate(20deg); }
.user-menu { position: relative; display: flex; align-items: center; gap: 12px; }
.user-menu-dropdown {
    display: none; position: absolute; right: 0; top: calc(100% + 8px);
    background: #fff; border-radius: 16px; box-shadow: 0 16px 48px rgba(0,0,0,0.08);
    min-width: 180px; overflow: hidden; z-index: 101;
    border: 1px solid rgba(0,0,0,0.06);
}
.user-menu-dropdown.active { display: block; animation: navDropIn 0.2s ease-out; }
@keyframes navDropIn { 0%{opacity:0;transform:translateY(-8px)} 100%{opacity:1;transform:translateY(0)} }
.user-menu-item {
    padding: 14px 18px; cursor: pointer; font-size: 14px;
    color: #1a2332; transition: all 0.3s;
    border-bottom: 1px solid rgba(0,0,0,0.06);
}
.user-menu-item:last-child { border-bottom: none; color: #e74c3c; }
.user-menu-item:hover { background: rgba(79,110,247,0.06); }
.message-icon { position: relative; font-size: 18px; cursor: pointer; color: #666; }
.message-badge {
    position: absolute; top: -5px; right: -5px;
    background: #ff4757; color: white; font-size: 10px;
    padding: 2px 6px; border-radius: 10px;
    min-width: 18px; text-align: center;
}

.hamburger {
    display: none; flex-direction: column; gap: 5px;
    cursor: pointer; padding: 4px; background: none; border: none; z-index: 200;
}
.hamburger span {
    display: block; width: 22px; height: 2px; background: #333;
    border-radius: 2px; transition: all 0.3s;
}
.hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

@media (max-width: 768px) {
    .hamburger { display: flex !important; }
    .nav-links {
        display: none !important; position: fixed; top: 64px; left: 0; right: 0;
        background: white; flex-direction: column; padding: 12px 0;
        box-shadow: 0 4px 12px rgba(0,0,0,0.1); z-index: 150; gap: 0;
    }
    .nav-links.mobile-open { display: flex !important; }
    .nav-links a {
        padding: 12px 20px; font-size: 15px; border-radius: 0;
        border-bottom: 1px solid #f0f0f0;
    }
    .nav-links a:hover, .nav-links a.active { background: #f5f5ff; }
    .user-menu { padding: 12px 20px; }
}

@media (max-width: 600px) {
    .nav-links a { padding: 5px 8px; font-size: 12px; }
}

body.dark-mode .navbar {
    background: rgba(20,28,40,0.88);
    border-bottom-color: rgba(255,255,255,0.06);
    box-shadow: 0 4px 20px rgba(0,0,0,0.2);
}
body.dark-mode .nav-brand a { color: #6b85f9; }
body.dark-mode .nav-links a { color: #94a3b8; }
body.dark-mode .nav-links a:hover { background: rgba(79,110,247,0.12); color: #6b85f9; }
body.dark-mode .nav-links a.active { background: #4f6ef7; color: #fff; }
body.dark-mode .hamburger span { background: #e2e8f0; }
body.dark-mode .nav-links { background: #1e293b; }
body.dark-mode .nav-links a { border-bottom-color: #334155; }
body.dark-mode .user-menu-dropdown {
    background: #1e293b; box-shadow: 0 4px 12px rgba(0,0,0,0.4);
}
body.dark-mode .user-menu-item {
    border-bottom-color: #334155; color: #e2e8f0;
}
body.dark-mode .user-menu-item:hover { background: #334155; }
body.dark-mode .dark-toggle { background: rgba(255,255,255,0.08); }
body.dark-mode .dark-toggle:hover { background: rgba(255,255,255,0.15); }