:root {
            --sidebar-width: 280px;
            --sidebar-collapsed-width: 60px;
            --primary-color: #2c3e50;
            --secondary-color: #34495e;
            --accent-color: #3498db;
            --text-light: #ecf0f1;
            --hover-color: #3498db;
            --shadow: 0 2px 10px rgba(0,0,0,0.1);
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            background-color: #f8f9fa;
            overflow-x: hidden;
        }

        /* Sidebar Styles */
        .sidebar {
            position: fixed;
            top: 0;
            left: 0;
            height: 100vh;
            width: var(--sidebar-width);
            background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
            transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
            z-index: 1000;
            box-shadow: var(--shadow);
            transform: translateX(-100%);
            display: flex;
            flex-direction: column;
        }

        .sidebar.show {
            transform: translateX(0);
        }

        .sidebar.collapsed {
            width: var(--sidebar-collapsed-width);
        }

        .sidebar-header {
            padding: 15px;
            border-bottom: 1px solid rgba(255,255,255,0.1);
            display: flex;
            align-items: center;
            justify-content: space-between;
            min-height: 65px;
        }

        .sidebar-header .brand {
            display: flex;
            align-items: center;
            min-width: 0;
            flex: 1;
        }

        .sidebar-header h3 {
            color: var(--text-light);
            font-size: 1.4rem;
            font-weight: 600;
            margin: 0;
            white-space: nowrap;
            transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }

        .sidebar.collapsed .sidebar-header h3 {
            opacity: 0;
            transform: translateX(-20px);
        }

        .sidebar-header .logo {
            color: var(--accent-color);
            font-size: 1.6rem;
            margin-right: 10px;
            flex-shrink: 0;
        }

        .collapse-btn {
            background: none;
            border: none;
            color: var(--text-light);
            font-size: 1rem;
            cursor: pointer;
            padding: 8px;
            border-radius: 4px;
            transition: all 0.3s ease;
            width: 32px;
            height: 32px;
            display: flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
        }

        .collapse-btn:hover {
            background-color: rgba(255,255,255,0.1);
        }

        .collapse-btn i {
            transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }

        .sidebar.collapsed .collapse-btn i {
            transform: rotate(180deg);
        }

        /* Navigation Styles */
        .nav-menu {
            flex: 1;
            padding: 15px 0;
            overflow-y: auto;
            overflow-x: hidden;
        }

        .nav-menu::-webkit-scrollbar {
            width: 4px;
        }

        .nav-menu::-webkit-scrollbar-track {
            background: rgba(255,255,255,0.1);
        }

        .nav-menu::-webkit-scrollbar-thumb {
            background: rgba(255,255,255,0.3);
            border-radius: 2px;
        }

        .nav-item {
            margin-bottom: 3px;
        }

        .nav-link {
            display: flex;
            align-items: center;
            padding: 12px 20px;
            color: var(--text-light);
            text-decoration: none;
            transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
            position: relative;
            border-radius: 0 25px 25px 0;
            margin-right: 15px;
            white-space: nowrap;
            min-height: 44px;
        }

        .nav-link:hover {
            background-color: rgba(255,255,255,0.1);
            color: var(--text-light);
            transform: translateX(5px);
        }

        .nav-link.active {
            background-color: var(--accent-color);
            color: white;
            box-shadow: 0 2px 8px rgba(52, 152, 219, 0.3);
        }

        .nav-link i {
            font-size: 1.1rem;
            margin-right: 12px;
            width: 18px;
            text-align: center;
            flex-shrink: 0;
            transition: all 0.3s ease;
        }

        .nav-link span {
            font-size: 0.95rem;
            font-weight: 500;
            transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
            overflow: hidden;
        }

        .sidebar.collapsed .nav-link {
            margin-right: 0;
            border-radius: 0;
            justify-content: center;
            padding: 12px 0;
        }

        .sidebar.collapsed .nav-link span {
            opacity: 0;
            width: 0;
            margin: 0;
        }

        .sidebar.collapsed .nav-link i {
            margin-right: 0;
        }

        /* Dropdown Styles - Setas Simples */
        .dropdown-toggle {
            position: relative;
        }

        .dropdown-toggle .dropdown-arrow {
            margin-left: auto;
            font-size: 0.8rem;
            transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }

        .dropdown-toggle[aria-expanded="true"] .dropdown-arrow {
            transform: rotate(180deg);
        }

        .sidebar.collapsed .dropdown-arrow {
            display: none;
        }

        .submenu {
            background-color: rgba(0,0,0,0.2);
            margin-top: 3px;
            border-radius: 8px;
            overflow: hidden;
            transition: all 0.3s ease;
        }

        .submenu .nav-link {
            padding: 10px 20px 10px 45px;
            font-size: 0.85rem;
            border-radius: 0;
            margin-right: 0;
            min-height: 40px;
        }

        .submenu .nav-link:hover {
            background-color: rgba(255,255,255,0.1);
            transform: translateX(3px);
        }

        .submenu .nav-link i {
            font-size: 0.9rem;
            width: 16px;
        }

        /* Mobile Toggle Button */
        .mobile-toggle {
            position: fixed;
            top: 20px;
            left: 20px;
            z-index: 1001;
            background: var(--primary-color);
            color: white;
            border: none;
            padding: 12px 15px;
            border-radius: 8px;
            box-shadow: var(--shadow);
            transition: all 0.3s ease;
        }

        .mobile-toggle:hover {
            background: var(--secondary-color);
            transform: scale(1.05);
        }

        .mobile-toggle.active {
            background: var(--accent-color);
        }

        /* Logout Button */
        .logout-section {
            padding: 15px;
            border-top: 1px solid rgba(255,255,255,0.1);
        }

        .logout-btn .nav-link {
            color: #e74c3c;
            border: 1px solid rgba(231, 76, 60, 0.3);
            margin-right: 15px;
            border-radius: 8px;
            background-color: rgba(231, 76, 60, 0.1);
        }

        .logout-btn .nav-link:hover {
            background-color: rgba(231, 76, 60, 0.2);
            color: #e74c3c;
            transform: translateX(0);
        }

        .sidebar.collapsed .logout-btn .nav-link {
            margin-right: 0;
            border-radius: 8px;
            justify-content: center;
            padding: 12px 0;
        }

        /* Tooltip para modo colapsado */
        .sidebar.collapsed .nav-link {
            position: relative;
        }

        .sidebar.collapsed .nav-link::after {
            content: attr(data-tooltip);
            position: absolute;
            left: 100%;
            top: 50%;
            transform: translateY(-50%);
            background: rgba(0,0,0,0.8);
            color: white;
            padding: 6px 12px;
            border-radius: 4px;
            font-size: 0.8rem;
            white-space: nowrap;
            opacity: 0;
            visibility: hidden;
            transition: all 0.3s ease;
            margin-left: 10px;
            z-index: 1000;
        }

        .sidebar.collapsed .nav-link:hover::after {
            opacity: 1;
            visibility: visible;
        }

        /* Responsive Design */
        @media (max-width: 768px) {
            .sidebar {
                width: var(--sidebar-width);
            }

            .sidebar.collapsed {
                width: var(--sidebar-width);
            }
        }

        @media (min-width: 769px) {
            .sidebar {
                transform: translateX(0);
            }

            .mobile-toggle {
                display: none;
            }
        }

        /* Overlay para mobile */
        .overlay {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-color: rgba(0,0,0,0.5);
            z-index: 999;
            opacity: 0;
            visibility: hidden;
            transition: all 0.3s ease;
        }

        .overlay.show {
            opacity: 1;
            visibility: visible;
        }

        /* Animations */
        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(10px); }
            to { opacity: 1; transform: translateY(0); }
        }

        .nav-item {
            animation: fadeIn 0.5s ease forwards;
        }

        .nav-item:nth-child(1) { animation-delay: 0.1s; }
        .nav-item:nth-child(2) { animation-delay: 0.2s; }
        .nav-item:nth-child(3) { animation-delay: 0.3s; }
        .nav-item:nth-child(4) { animation-delay: 0.4s; }