I was a victim of the WordPress pharmacy hack, and I think I've fixed the problem for now. I had been very bad about updating WordPress, and I think that was the main problem (I've updated WP and all plug-ins, and am using the WP Security Scan plugin).
Anyway, in researching this, I see frequent recommendations to add/modify the .htaccess file to restrict access from the outside. I'm using Cyberduck and turning on 'view hidden files' and it doesn't appear I've had an .htaccess file up to now. I created a file, containing the recommended commands:
<Files wp-config.php>
Order Allow,Deny
Deny from all
</Files>
but when I upload it I lose all access to the site. I put the file in the main folder for my website. My website is http://www.synchrolux.com. Any recommendations?