.secure-mailto-overlay {position: fixed;top: 0;left: 0;width: 100%;height: 100%;background: rgba(0, 0, 0, 0.5);z-index: 99999;display: flex;justify-content: center;align-items: center;opacity: 0;visibility: hidden;transition: opacity 0.3s ease;}.secure-mailto-overlay.is-visible {opacity: 1;visibility: visible;}.secure-mailto-modal {background: #fff;padding: 2rem;border-radius: 8px;box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);width: 90%;max-width: 400px;text-align: center;position: relative;}.secure-mailto-modal h3 {margin-top: 0;margin-bottom: 1rem;font-size: 1.5rem;color: #333;}.secure-mailto-close {position: absolute;top: 10px;right: 15px;font-size: 24px;cursor: pointer;color: #999;}.secure-mailto-close:hover {color: #333;}.secure-mailto-challenge-content {margin-bottom: 1.5rem;}.secure-mailto-input {width: 100%;padding: 10px;margin: 10px 0;border: 1px solid #ddd;border-radius: 4px;font-size: 16px;}.secure-mailto-btn {background: #0073aa;color: #fff;border: none;padding: 10px 20px;border-radius: 4px;cursor: pointer;font-size: 16px;transition: background 0.3s;}.secure-mailto-btn:hover {background: #005177;}.secure-mailto-error {color: #dc3232;margin-top: 10px;font-size: 14px;display: none;}