:root {
            --primary-color: #1e40af; /* Vibrant blue for brand consistency */
            --primary-dark: #1e3a8a; /* Dark blue for hover effects */
            --secondary-color: #000000; /* Black for text and headings */
            --text-color: #4b5563; /* Softer gray for secondary text */
            --white: #ffffff;
            --gray-light: #f9fafb; /* Light background for inputs */
            --error-color: #e11d48; /* Bold red for errors */
            --success-color: #15803d; /* Green for success messages */
            --border-radius: 12px; /* Softer, modern corners */
            --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
            --shadow: 0 12px 24px rgba(0, 0, 0, 0.15);
            --shadow-hover: 0 16px 28px rgba(0, 0, 0, 0.2);
        }

        body {
            font-family: 'Inter', 'Lato', sans-serif; /* Modern font with fallback */
            background: linear-gradient(145deg, rgba(0, 0, 0, 0.75) 0%, rgba(0, 0, 0, 0.55) 100%), url('https://themes.g5plus.net/darna/wp-content/uploads/revslider/home-1/slider-01.jpg');
            background-size: cover;
            background-position: center;
            background-attachment: fixed;
            min-height: 100vh;
            display: flex;
            justify-content: center;
            align-items: center;
            margin: 0;
            color: var(--text-color);
            line-height: 1.6;
        }

        .login-container, .register-container, .verification-container {
            background: var(--white);
            padding: 2.5rem;
            border-radius: var(--border-radius);
            box-shadow: var(--shadow);
            width: 100%;
            max-width: 460px; /* Optimized for login form */
            text-align: center;
            animation: fadeInUp 0.6s ease-out;
            backdrop-filter: blur(10px); /* Enhanced glassmorphism */
            border: 1px solid rgba(255, 255, 255, 0.1);
        }

        @keyframes fadeInUp {
            from { opacity: 0; transform: translateY(30px); }
            to { opacity: 1; transform: translateY(0); }
        }

        .login-container h2, .register-container h2, .verification-container h2 {
            color: var(--secondary-color);
            font-family: 'Oswald', sans-serif;
            font-size: 2.25rem;
            font-weight: 700;
            margin-bottom: 1.75rem;
            letter-spacing: 0.75px;
            text-transform: uppercase; /* Adds emphasis to headings */
        }

        .form-group {
            margin-bottom: 1.75rem;
            text-align: left;
            position: relative; /* For error positioning */
        }

        .form-group label {
            font-size: 0.95rem;
            font-weight: 600;
            color: var(--secondary-color);
            margin-bottom: 0.5rem;
            display: block;
            transition: color 0.2s ease;
        }

        .form-control {
            border: 1px solid #d1d5db;
            border-radius: var(--border-radius);
            padding: 0.85rem 1.25rem;
            font-size: 1rem;
            color: var(--secondary-color);
            background-color: var(--gray-light);
            transition: var(--transition);
            width: 100%;
            box-sizing: border-box;
        }

        .form-control:focus {
            border-color: var(--primary-color);
            box-shadow: 0 0 12px rgba(30, 64, 175, 0.4);
            background-color: var(--white);
            outline: none;
        }

        .form-control::placeholder {
            color: #9ca3af;
            opacity: 0.8;
        }

        .form-control[aria-invalid="true"] {
            border-color: var(--error-color);
            box-shadow: 0 0 8px rgba(225, 29, 72, 0.3);
        }

        .btn-primary {
            background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
            border: none;
            color: var(--white);
            padding: 0.9rem 1.5rem;
            border-radius: var(--border-radius);
            font-size: 1.1rem;
            font-weight: 600;
            width: 100%;
            cursor: pointer;
            transition: var(--transition);
            letter-spacing: 0.5px;
        }

        .btn-primary:hover {
            background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
            color: var(--white);
            transform: translateY(-3px);
            box-shadow: var(--shadow-hover);
        }

        .btn-primary:active {
            transform: translateY(0);
            box-shadow: var(--shadow);
        }

        .btn-primary:disabled {
            background: #d1d5db;
            color: #6b7280;
            cursor: not-allowed;
            transform: none;
            box-shadow: none;
        }

        .text-secondary {
            color: var(--text-color);
            font-size: 0.95rem;
            margin-top: 1.5rem;
            font-weight: 500;
        }

        .text-secondary a {
            color: var(--primary-color);
            text-decoration: none;
            font-weight: 600;
            transition: color 0.2s ease;
        }

        .text-secondary a:hover {
            color: var(--primary-dark);
            text-decoration: underline;
            transform: scale(1.02); /* Subtle hover effect */
        }

        .alert {
            font-size: 0.95rem;
            margin-bottom: 1.5rem;
            padding: 0.85rem 1rem;
            border-radius: var(--border-radius);
            text-align: left;
            border: 1px solid transparent;
            animation: fadeIn 0.4s ease-in;
        }

        .alert-success {
            background-color: #dcfce7;
            color: var(--success-color);
            border-color: var(--success-color);
        }

        .alert-error, .alert-info {
            background-color: #ffe4e6;
            color: var(--error-color);
            border-color: var(--error-color);
        }

        .error {
            color: var(--error-color);
            font-size: 0.85rem;
            margin-top: 0.5rem;
            text-align: left;
            font-weight: 500;
            display: block;
            animation: fadeIn 0.3s ease-in;
        }

        @keyframes fadeIn {
            from { opacity: 0; }
            to { opacity: 1; }
        }

        /* Accessibility improvements */
        .form-control:focus-visible {
            outline: 3px solid var(--primary-color);
            outline-offset: 3px;
        }

        .btn-primary:focus-visible {
            outline: 3px solid var(--primary-dark);
            outline-offset: 3px;
        }

        /* Navigation buttons for base.html */
        .btn-login, .btn-quote {
            background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
            color: var(--white);
            padding: 0.5rem 1rem;
            border-radius: var(--border-radius);
            text-decoration: none;
            font-weight: 600;
            transition: var(--transition);
        }

        .btn-login:hover, .btn-quote:hover {
            background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
            color: var(--white);
            transform: translateY(-2px);
            box-shadow: var(--shadow-hover);
        }

        .btn-search, .btn-cart {
            background: var(--gray-light);
            color: var(--secondary-color);
            padding: 0.5rem;
            border: none;
            border-radius: var(--border-radius);
            transition: var(--transition);
        }

        .btn-search:hover, .btn-cart:hover {
            background: var(--primary-color);
            color: var(--white);
            transform: scale(1.1);
        }

        /* Verification container animation */
        .verification-container {
            animation: slideIn 0.5s ease-out;
        }

        @keyframes slideIn {
            from { opacity: 0; transform: translateX(20px); }
            to { opacity: 1; transform: translateX(0); }
        }

        /* Password strength indicator */
        .password-strength {
            margin-top: 5px;
            font-size: 0.875rem;
        }

        .strength-weak { color: #dc3545; }
        .strength-fair { color: #fd7e14; }
        .strength-good { color: #ffc107; }
        .strength-strong { color: #198754; }

        /* Logo styling */
        .logo {
            margin-bottom: 1.5rem;
        }

        .logo img {
            max-height: 60px;
        }

        /* Social login buttons */
        .social-login {
            margin-top: 1.5rem;
            display: flex;
            gap: 10px;
        }

        .social-btn {
            flex: 1;
            padding: 0.75rem;
            border: 1px solid #d1d5db;
            border-radius: var(--border-radius);
            background: var(--white);
            color: var(--secondary-color);
            font-weight: 500;
            transition: var(--transition);
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
        }

        .social-btn:hover {
            background: var(--gray-light);
            transform: translateY(-2px);
        }

        .social-btn.google {
            color: #db4437;
        }

        .social-btn.facebook {
            color: #4267B2;
        }

        /* Divider */
        .divider {
            display: flex;
            align-items: center;
            margin: 1.5rem 0;
            color: var(--text-color);
        }

        .divider::before,
        .divider::after {
            content: "";
            flex: 1;
            border-bottom: 1px solid #d1d5db;
        }

        .divider span {
            padding: 0 1rem;
            font-size: 0.9rem;
        }

        /* Remember me checkbox */
        .remember-me {
            display: flex;
            align-items: center;
            gap: 8px;
            margin-bottom: 1rem;
        }

        .remember-me input[type="checkbox"] {
            accent-color: var(--primary-color);
        }

        /* Responsive adjustments */
        @media (max-width: 576px) {
            .login-container, .register-container, .verification-container {
                padding: 1.75rem;
                max-width: 95%;
                margin: 1rem;
            }

            .login-container h2, .register-container h2, .verification-container h2 {
                font-size: 1.8rem;
                margin-bottom: 1.25rem;
            }

            .form-control {
                font-size: 0.95rem;
                padding: 0.75rem 1rem;
            }

            .btn-primary {
                font-size: 1rem;
                padding: 0.8rem 1.25rem;
            }

            .alert, .error, .text-secondary {
                font-size: 0.9rem;
            }

            .text-secondary {
                margin-top: 1rem;
            }

            .social-login {
                flex-direction: column;
            }
        }