defineExpose and <style vars> in Vue 3 for component interaction and theming

As Vue.js applications grow in complexity, managing component interactions and dynamic styling becomes increasingly challenging. The defineExpose feature and <style vars> syntax in Vue 3 offer solutions by enhancing component interaction and allowing dynamic theming, respectively. defineExpose allows developers to control which properties and methods are accessible externally, thereby simplifying code maintenance and improving component encapsulation. Meanwhile, <style vars> facilitates dynamic theming by enabling developers to switch themes through CSS variables linked to reactive properties, ensuring seamless updates in component styling. When used together, these features make Vue components more flexible, allowing for dynamic state management and appearance customization from parent components. This approach is particularly beneficial for applications that require global theme management and user-initiated style modifications while maintaining component-specific states.