Configure the theme on HTTPS (SSL certificate)
To use the theme on HTTPS instead of HTTP a SSL certificate need to be installed on your server. The best is to get in touch with your hosting company if you're not familiar with this.
After the SSL certificate is running on your server there are a few steps to take to make WordPress and the theme work correctly.
The first things is to change the Home URL and Site URL under Settings -> General. Please make sure before changing this your website is accessible through HTTPS, if this is not the case your website will not be working anymore and these settings need to be restored through ftp.
Please install and activate the Really Simple SSL plugin and active the SSL option via Settings -> SSL
The last step is to take a look at the front-end of your website and check if all images are loading correctly. If the logo doesn't display please remove it from the customizer option and add it back to save the image with the correct path.