The safest way to get themes is directly through your OJS administration dashboard: Log in as an . Navigate to Settings > Website > Plugins . Go to the Plugin Gallery tab.
Filter by "Themes" to install official options like Manuscript , Classic , or Immersion with a single click. 2. PKP's Official GitHub Repositories
Locate the theme in your "Installed Plugins" list, check the enable box, and then select it from your Appearance settings tab.
Many developers host professional OJS 3 themes on GitHub for free. Some popular options include: