I need to apply CSS codes to buttons, divs, paragraphs, etc. making responsive curved sides that shrinks and expands automatically according to the content and doesn't get blurred.
I'd prefer a style to apply on as many elements as possible with minimum changes (like color and padding).
Using backgroud-image property or SVG isn't preferred.

Try something like this.
This is a close implementation of what you are trying to achieve
https://jsfiddle.net/rahulSlash/qva79at5/
The html code is as follows
And CSS goes: