The maintainers of Vue.js have recently published their official style guide.

This is the official style guide for Vue-specific code. If you use Vue in a project, it’s a great reference to avoid errors, bikeshedding, and anti-patterns. However, we don’t believe that any style guide is ideal for all teams or projects, so mindful deviations are encouraged based on past experience, the surrounding tech stack, and personal values. For the most part, we also avoid suggestions about JavaScript or HTML in general. We don’t mind whether you use semicolons or trailing commas. We don’t mind whether your HTML uses single-quotes or double-quotes for attribute values. Some exceptions will exist however, where we’ve found that a particular pattern is helpful in the context of Vue.

https://vuejs.org/v2/style-guide/

Want to see some more style guides? At Spatie we have a guidelines site containing styleguides for Laravel and JavaScript.

This site contains a set of guidelines we use to bring our projects to a good end. We decided to document our workflow because consistency is one of the most valuable traits of maintainable software. The contents of this site exist for ourselves—more importantly, our future selves—and for giving future collegues a reference to our way of doing things and their quirks. The guidelines cover workflow, code style, and other little things we consider worth documenting.

https://guidelines.spatie.be