Basically 'course' folder contains all the files of course created in Lectora.
In www/index.html file, there is button. On click of this, the page redirects to course/index.html (window.location.href = 'course/index.html')
First page (index.html in www folder) displays properly. No horizontal scroll. When I click on button, a horizontal scrollbar comes. This is observed in Samsung Tablet 4.(Android Version 4.4.2). However, it is running proprely in nexus 7 (Android 6.0).