body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; display: flex; justify-content: center; align-items: center; min-height: 100vh; background-color: #f0f2f5; margin: 0; }
        .container { background: #fff; padding: 2rem; border-radius: 10px; box-shadow: 0 4px 12px rgba(0,0,0,0.1); width: 100%; max-width: 400px; }
        h1, h2 { text-align: center; color: #1c1e21; }
        .input-group, .radio-group { margin-bottom: 1rem; }
        label { display: block; margin-bottom: 0.5rem; color: #606770; }
        input[type="radio"] { margin-right: 0.5rem; }
        input[type="text"], input[type="email"], input[type="tel"], input[type="password"] { width: 100%; padding: 0.75rem; border-radius: 6px; border: 1px solid #ddd; box-sizing: border-box; font-size: 1rem; }
        button { width: 100%; padding: 0.75rem; border: none; border-radius: 6px; background-color: #1877f2; color: #fff; font-size: 1rem; font-weight: bold; cursor: pointer; transition: background-color 0.2s; }
        button:hover { background-color: #166fe5; }
        button.secondary { background-color: #e4e6eb; color: #1c1e21; margin-top: 0.5rem; }
        button.secondary:hover { background-color: #d8dbdf; }
        #status { text-align: center; margin-top: 1rem; font-weight: bold; }
        .hidden { display: none; }