:root {
            --primary: #3498db;
            --secondary: #2c3e50;
            --accent: #e74c3c;
            --light: #ecf0f1;
            --dark: #2c3e50;
            --success: #2ecc71;
            --warning: #f39c12;
            --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
            --transition: all 0.3s ease;
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }

        body {
            background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            color: #333;
            line-height: 1.6;
        }

        .container {
            width: 90%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 15px;
        }

        .btn {
            display: inline-block;
            padding: 12px 24px;
            background: var(--primary);
            color: white;
            border: none;
            border-radius: 4px;
            cursor: pointer;
            text-decoration: none;
            font-weight: 600;
            transition: var(--transition);
            text-align: center;
        }

        .btn:hover {
            background: #2980b9;
            transform: translateY(-2px);
        }

        .btn-secondary {
            background: var(--secondary);
        }

        .btn-secondary:hover {
            background: #1a252f;
        }

        .btn-accent {
            background: var(--accent);
        }

        .btn-accent:hover {
            background: #c0392b;
        }

        .btn-full {
            width: 100%;
        }

        .btn-outline {
            background: transparent;
            border: 2px solid var(--primary);
            color: var(--primary);
        }

        .btn-outline:hover {
            background: var(--primary);
            color: white;
        }

        header {
            background: white;
            box-shadow: var(--shadow);
            position: sticky;
            top: 0;
            z-index: 1000;
        }

        .navbar {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 15px 0;
        }

        .logo {
            display: flex;
            align-items: center;
            font-size: 1.8rem;
            font-weight: 700;
            color: var(--primary);
            text-decoration: none;
        }

        .logo i {
            margin-right: 10px;
            font-size: 2rem;
        }

        .back-link {
            color: var(--primary);
            text-decoration: none;
            font-weight: 600;
            display: flex;
            align-items: center;
            gap: 5px;
        }

        .back-link:hover {
            text-decoration: underline;
        }

        .main-content {
            flex: 1;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 40px 0;
        }

        .login-container {
            background: white;
            border-radius: 10px;
            box-shadow: var(--shadow);
            width: 100%;
            max-width: 500px;
            overflow: hidden;
        }

        .login-header {
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            color: white;
            padding: 30px;
            text-align: center;
        }

        .login-header h1 {
            font-size: 2rem;
            margin-bottom: 10px;
        }

        .login-header p {
            opacity: 0.9;
        }

        .login-tabs {
            display: flex;
            border-bottom: 1px solid #eee;
        }

        .tab-button {
            flex: 1;
            padding: 15px;
            background: none;
            border: none;
            font-size: 1rem;
            font-weight: 600;
            cursor: pointer;
            transition: var(--transition);
            color: #666;
        }

        .tab-button.active {
            color: var(--primary);
            border-bottom: 3px solid var(--primary);
        }

        .login-form {
            padding: 30px;
            display: none;
        }

        .login-form.active {
            display: block;
        }

        .form-group {
            margin-bottom: 20px;
        }

        .form-group label {
            display: block;
            margin-bottom: 8px;
            font-weight: 600;
            color: var(--secondary);
        }

        .form-control {
            width: 100%;
            padding: 12px 15px;
            border: 1px solid #ddd;
            border-radius: 4px;
            font-size: 1rem;
            transition: var(--transition);
        }

        .form-control:focus {
            border-color: var(--primary);
            outline: none;
            box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
        }

        .password-toggle {
            position: relative;
        }

        .password-toggle .form-control {
            padding-right: 40px;
        }

        .toggle-password {
            position: absolute;
            right: 10px;
            top: 50%;
            transform: translateY(-50%);
            background: none;
            border: none;
            color: #666;
            cursor: pointer;
        }

        .form-footer {
            margin-top: 30px;
            text-align: center;
        }

        .form-footer p {
            margin-top: 20px;
            color: #666;
        }

        .form-footer a {
            color: var(--primary);
            text-decoration: none;
            font-weight: 600;
        }

        .form-footer a:hover {
            text-decoration: underline;
        }

        .forgot-password {
            text-align: right;
            margin-top: 10px;
        }

        .forgot-password a {
            color: #666;
            text-decoration: none;
            font-size: 0.9rem;
        }

        .forgot-password a:hover {
            color: var(--primary);
            text-decoration: underline;
        }

        footer {
            background: var(--secondary);
            color: white;
            padding: 30px 0 20px;
            margin-top: auto;
        }

        .footer-content {
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: 20px;
        }

        .footer-links {
            display: flex;
            gap: 20px;
        }

        .footer-links a {
            color: #bdc3c7;
            text-decoration: none;
            transition: var(--transition);
        }

        .footer-links a:hover {
            color: white;
        }

        .copyright {
            text-align: center;
            padding-top: 20px;
            margin-top: 20px;
            border-top: 1px solid #34495e;
            color: #bdc3c7;
            font-size: 0.9rem;
            width: 100%;
        }

        .alert {
            padding: 15px;
            border-radius: 4px;
            margin-bottom: 20px;
        }

        .alert-error {
            background: #f8d7da;
            color: #721c24;
            border: 1px solid #f5c6cb;
        }

        @media (max-width: 576px) {
            .login-header h1 {
                font-size: 1.7rem;
            }
            
            .login-form {
                padding: 20px;
            }
            
            .footer-content {
                flex-direction: column;
                text-align: center;
            }
        }