CSS Introduction, Types & Selectors

1. What is CSS?

CSS (Cascading Style Sheets) is used to style HTML elements, control layout, colors, fonts, and more. It separates content (HTML) from presentation (design).

2. Types of CSS

A. Inline CSS

This is inline CSS

B. Internal CSS

This text is styled using internal CSS (blue color for all <p> elements).

C. External CSS

External CSS is written in a separate .css file and linked with <link>. (Not shown here, but works like internal CSS.)

🎨 Color System

color → red text

background-color → lightblue background

border-color → green border

opacity → semi-transparent purple

Name → blue

HEX → #ff0000 red

RGB → rgb(0,128,0) green

RGBA → rgba(255,0,0,0.5) semi-transparent red

HSL → hsl(200,100%,40%) teal blue

HSLA → hsla(300,100%,40%,0.6) semi-transparent purple