By default, styles written in .vue components will take effect globally, so it is easy to cause style conflicts between multiple components.
The root causes of style conflicts between components are:
① In a single-page application, the DOM structure of all components is presented based on the unique index.html page
② The styles in each component will affect the DOM elements in the entire index.html page
Style conflict resolution:
principle:
use:
When not added, more precisely, it is not its own son in the parent component, and the property is not automatically added
Instance object of V ue component
