Update introduction.md

Using 'and' between declarative and component-based implies (grammatically speaking) a direct connection between the concepts, as if they are in some sense one. This is not the case. Also, the bit about complexity is over-wrought and clunky. I simplified it.

src/guide/introduction.md

@@ -25,7 +25,7 @@ footer: false
 
 ## What is Vue? {#what-is-vue}
 
-Vue (pronounced /vjuː/, like **view**) is a JavaScript framework for building user interfaces. It builds on top of standard HTML, CSS, and JavaScript and provides a declarative and component-based programming model that helps you efficiently develop user interfaces, be they simple or complex.
+Vue (pronounced /vjuː/, like **view**) is a JavaScript framework for building user interfaces. It builds on top of standard HTML, CSS, and JavaScript and provides a declarative, component-based programming model that helps you efficiently develop user interfaces of any complexity.
 
 Here is a minimal example: