What is the difference between HTML and CSS

HTML = Content; That is, we put only content in our page from HTML, here content means: text, heading, paragraph, image, video, audio, bullet lists etc. Apart from this, the structure of the web page is also made from HTML.

CSS = Design; Now we tell in CSS what will be the color, background, size, border, position etc. of that content. That is, CSS decides how the content will appear in the browser.
Suppose we are writing an article in the website which will have a heading i.e. title and there will be paragraphs, in this case only HTML tells the browser which is the heading and which is the paragraph, while CSS will tell that the color of those headings and paragraphs. And what will be the size.