   align-items: center;
            height: 100vh;
        }

        .container {
            background-color: #ffffff;
            border-radius: 8px;
            box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
            padding: 2rem;
            width: 640px;
            transition: width 0.3s ease;
        }

        .container.expanded {
            width: 800px;
        }

        h1 {
            color: #3498db;
            text-align: center;
        }

        .input-group {
            margin-bottom