https://css-tricks.com/ → 前端 教程、问答 社区
HTML：Hyper Text Markup Language
HyperText, is text which contains links to other texts, i.e. one document points to another document which points to a bunch of other documents.
Hypermedia: video, audio, etc, is just an extension of hypertext.
Markup, means to mark sth up, to annotate, to tell the browser or other machine what the content is and that’s what HTML does, by wrapping the content in some markup languages like tags.
HTML —> Structure, means what components does the HTML document has, for example, heading, paragraphs, footer, BUT does NOT tell you anything about how these components are visually laid out, NO color, NO font, NO size. —> Annotates content, Defines document structure.
CSS —> Style, color, style, font.
browsersync (npm install -g browser-sync)