It could be a symbol representing something specific in the story's context. Maybe it's related to a character's vision or a metaphor for seeing things differently.
Yes, there are several. Many comic book publishers have their own official websites or apps where you can read their comics online. Also, there are some dedicated comic reading platforms that offer a wide range of titles.
Sure. Nowadays, there are numerous online libraries and comic book apps where you can enjoy reading comics. Just make sure to choose legal and reliable sources.