/* Thanh điều hướng chính */
.main-navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: #2c3e50; /* Màu xanh đen chuyên nghiệp */
    padding: 10px 25px;
    color: white;
    position: sticky;
    top: 0;
    z-index: 9999;
    box-shadow: 0 2px 10px rgba(0,0,0,0.3);
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.nav-links {
    display: flex;
    gap: 15px;
}

.nav-links a {
    color: #ecf0f1;
    text-decoration: none;
    font-weight: bold;
    padding: 10px 15px;
    border-radius: 6px;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-links a:hover {
    background-color: #34495e;
    color: #3498db;
    transform: translateY(-2px);
}

.nav-links a.active {
    background-color: #3498db;
    color: white;
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
}

.nav-user {
    display: flex;
    align-items: center;
    gap: 20px;
}

.nav-user span {
    font-weight: 500;
    color: #bdc3c7;
}

.logout-btn {
    background-color: #e74c3c;
    color: white;
    border: none;
    padding: 8px 16px;
    border-radius: 6px;
    cursor: pointer;
    font-weight: bold;
    transition: background 0.3s;
}

.logout-btn:hover {
    background-color: #c0392b;
}

/* Responsive cho điện thoại */
@media (max-width: 768px) {
    .main-navbar {
        flex-direction: column;
        gap: 10px;
        padding: 15px;
    }
    .nav-links {
        width: 100%;
        justify-content: center;
    }
}