I think reading the following thread will be helpful to you. It explains which button types there are in B4W with links to examples:https://www.blend4web.com/en/forums/topic/5009/?page=1#post-22903
However, if you want to use HTML buttons and want them to run your Logic Node actions, the simplest way would be to let the HTML buttons run Entry Points. That means whenever the user clicks a button, an Entry Point Logic Node in your Logic Tree is called. This is still quite simple and only requires a minimal amount of coding for each button, namely the following onClick portion:
<button type="button" onclick="b4w.require('logic_nodes').run_entrypoint('my_scene_name','my_logic_node_name')">Click Me!</button>
If you put this button in your HTML, clicking the button will run the specified Entry Point Logic Node. You only need to fill in the names:
- "my_logic_node_name" is the name of your Entry Point node - you can rename nodes in the property panel (KEY N) in Blender. Don't forget to check the option RUN FROM SCRIPT in that node because otherwise it will be run right from the start of the scene, which is not what you want!
- "my_scene_name" is the name of your scene - it's usually simply "Scene" (can be renamed in the menu bar in Blender).