/* Base Styles */
        :root {
            --primary: #6366f1;
            --primary-light: #818cf8;
            --primary-dark: #4f46e5;
            --accent: #f59e0b;
            --success: #10b981;
            --danger: #ef4444;
            --text-primary: #f3f4f6;
            --text-secondary: #9ca3af;
            --bg-primary: #0f172a;
            --bg-secondary: #1e293b;
            --bg-card: #1e293b;
            --border-color: #334155;
            --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.2);
            --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -1px rgba(0, 0, 0, 0.1);
            --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.3), 0 4px 6px -2px rgba(0, 0, 0, 0.2);
            --radius-sm: 6px;
            --radius-md: 10px;
            --radius-lg: 16px;
            --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
        }

        [data-theme="light"] {
            --primary: #6366f1;
            --primary-light: #818cf8;
            --primary-dark: #4f46e5;
            --accent: #f59e0b;
            --success: #10b981;
            --danger: #ef4444;
            --text-primary: #1f2937;
            --text-secondary: #4b5563;
            --bg-primary: #f9fafb;
            --bg-secondary: #ffffff;
            --bg-card: #ffffff;
            --border-color: #e5e7eb;
            --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
            --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
            --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.05), 0 4px 6px -2px rgba(0, 0, 0, 0.03);
        }

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

        html {
            font-size: 16px;
            scroll-behavior: smooth;
        }

        body {
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
            color: var(--text-primary);
            background-color: var(--bg-primary);
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            background-image: radial-gradient(circle at 10% 20%, rgba(99, 102, 241, 0.1) 0%, transparent 20%), radial-gradient(circle at 90% 80%, rgba(245, 158, 11, 0.1) 0%, transparent 20%);
        }

        /* Registration Container */
        .registration-container {
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            min-height: 100vh;
            width: 100%;
            padding: 2rem;
        }

        .registration-card {
            background-color: var(--bg-card);
            border-radius: var(--radius-lg);
            border: 1px solid var(--border-color);
            box-shadow: var(--shadow-lg);
            width: 100%;
            max-width: 500px;
            padding: 2.5rem;
            transition: var(--transition);
            position: relative;
            overflow: hidden;
        }

        .registration-card::before {
            content: "";
            position: absolute;
            top: -50%;
            right: -50%;
            width: 200px;
            height: 200px;
            background: radial-gradient(circle, rgba(99, 102, 241, 0.2) 0%, rgba(99, 102, 241, 0) 70%);
            border-radius: 50%;
            z-index: 1;
        }

        .registration-header {
            text-align: center;
            margin-bottom: 2rem;
            position: relative;
            z-index: 2;
        }

        .logo-container {
            display: flex;
            justify-content: center;
            margin-bottom: 1.5rem;
        }

        .registration-logo {
            width: 70px;
            height: 70px;
            background: linear-gradient(135deg, var(--primary), var(--primary-dark));
            border-radius: 20px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: white;
            font-size: 1.8rem;
            font-weight: 700;
            box-shadow: 0 4px 10px rgba(99, 102, 241, 0.3);
        }

        .registration-title {
            font-size: 1.8rem;
            font-weight: 700;
            margin-bottom: 0.5rem;
            background: linear-gradient(to right, var(--primary), var(--accent));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }

        .registration-subtitle {
            color: var(--text-secondary);
            font-size: 1.1rem;
            margin-bottom: 2rem;
        }

        .registration-form {
            position: relative;
            z-index: 2;
        }

        .form-group {
            margin-bottom: 1.5rem;
            position: relative;
        }

        .form-label {
            display: block;
            margin-bottom: 0.5rem;
            font-weight: 500;
            color: var(--text-primary);
            font-size: 0.95rem;
        }

        .input-with-icon {
            position: relative;
        }

        .form-icon {
            position: absolute;
            left: 1rem;
            top: 50%;
            transform: translateY(-50%);
            color: var(--text-secondary);
            font-size: 1.1rem;
            z-index: 2;
        }

        .form-control {
            width: 100%;
            padding: 0.9rem 1rem 0.9rem 3rem;
            background-color: var(--bg-secondary);
            border: 1px solid var(--border-color);
            border-radius: var(--radius-md);
            color: var(--text-primary);
            font-family: 'Inter', sans-serif;
            font-size: 1rem;
            transition: var(--transition);
        }

        .form-control:focus {
            outline: none;
            border-color: var(--primary-light);
            box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
        }

        .password-strength {
            height: 6px;
            background-color: var(--bg-secondary);
            border-radius: 3px;
            margin-top: 0.5rem;
            overflow: hidden;
        }

        .strength-meter {
            height: 100%;
            width: 0;
            background-color: var(--danger);
            transition: var(--transition);
        }

        .password-rules {
            margin-top: 0.5rem;
            font-size: 0.85rem;
            color: var(--text-secondary);
        }

        .password-rules ul {
            padding-left: 1.2rem;
            margin-top: 0.3rem;
        }

        .password-rules li {
            margin-bottom: 0.2rem;
        }

        .password-rules .valid {
            color: var(--success);
        }

        .form-footer {
            display: flex;
            align-items: center;
            justify-content: space-between;
            margin-top: 1rem;
            font-size: 0.95rem;
        }

        .remember-me {
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }

        .remember-me input {
            accent-color: var(--primary);
        }

        .forgot-password {
            color: var(--primary-light);
            text-decoration: none;
            transition: var(--transition);
        }

        .forgot-password:hover {
            text-decoration: underline;
        }

        .submit-btn {
            display: block;
            width: 100%;
            padding: 1rem;
            background: linear-gradient(135deg, var(--primary), var(--primary-dark));
            color: white;
            border: none;
            border-radius: var(--radius-md);
            font-weight: 600;
            font-size: 1.1rem;
            cursor: pointer;
            transition: var(--transition);
            margin: 1.5rem 0;
            position: relative;
            overflow: hidden;
        }

        .submit-btn:hover {
            opacity: 0.9;
            transform: translateY(-2px);
            box-shadow: 0 4px 10px rgba(99, 102, 241, 0.4);
        }

        .submit-btn:active {
            transform: translateY(0);
        }

        .divider {
            display: flex;
            align-items: center;
            text-align: center;
            margin: 1.5rem 0;
            color: var(--text-secondary);
            font-size: 0.9rem;
        }

        .divider::before,
        .divider::after {
            content: '';
            flex: 1;
            border-bottom: 1px solid var(--border-color);
        }

        .divider::before {
            margin-right: 1rem;
        }

        .divider::after {
            margin-left: 1rem;
        }

        .social-login {
            display: flex;
            flex-direction: column;
            gap: 1rem;
            margin-bottom: 1.5rem;
        }

        .social-btn {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 0.8rem;
            padding: 0.9rem;
            border-radius: var(--radius-md);
            border: 1px solid var(--border-color);
            background-color: var(--bg-secondary);
            color: var(--text-primary);
            font-weight: 500;
            cursor: pointer;
            transition: var(--transition);
        }

        .social-btn:hover {
            background-color: rgba(255, 255, 255, 0.05);
        }

        .social-btn.google {
            color: #4285F4;
        }

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

        .social-btn.twitter {
            color: #1DA1F2;
        }

        .login-link {
            text-align: center;
            margin-top: 1.5rem;
            color: var(--text-secondary);
            font-size: 1rem;
        }

        .login-link a {
            color: var(--primary-light);
            text-decoration: none;
            font-weight: 600;
            margin-left: 0.5rem;
            transition: var(--transition);
        }

        .login-link a:hover {
            text-decoration: underline;
        }

        /* Theme Toggle */
        .theme-toggle {
            position: fixed;
            top: 1.5rem;
            right: 1.5rem;
            width: 50px;
            height: 50px;
            border-radius: 50%;
            background-color: var(--bg-card);
            color: var(--text-primary);
            border: 1px solid var(--border-color);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.4rem;
            cursor: pointer;
            z-index: 30;
            transition: var(--transition);
            box-shadow: var(--shadow-sm);
        }

        .theme-toggle:hover {
            transform: rotate(15deg);
            background-color: var(--bg-secondary);
        }

        /* Responsive Design */
        @media (max-width: 768px) {
            .registration-card {
                padding: 1.8rem;
            }
            
            .registration-title {
                font-size: 1.6rem;
            }
            
            .registration-subtitle {
                font-size: 1rem;
            }
            
            .form-footer {
                flex-direction: column;
                align-items: flex-start;
                gap: 1rem;
            }
        }

        @media (max-width: 480px) {
            .registration-card {
                padding: 1.5rem;
            }
            
            .registration-title {
                font-size: 1.4rem;
            }
            
            .registration-logo {
                width: 60px;
                height: 60px;
                font-size: 1.5rem;
            }
        }

        /* Animations */
        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(20px); }
            to { opacity: 1; transform: translateY(0); }
        }

        .fade-in {
            animation: fadeIn 0.6s ease-out forwards;
        }

        .strength-weak { background-color: var(--danger); }
        .strength-medium { background-color: var(--accent); }
        .strength-strong { background-color: var(--success); }