CSS is like the skin or clothes of a webpage. It styles the HTML elements to make them visually appealing.

Key Concepts:

1. Selectors:
   • CSS applies styles to HTML elements using selectors. A selector is a way to “select” the HTML elements you want to style.
     • Example: p { color: blue; }
     • Here, the selector is p, and it applies the style to all <p> elements on the page.
2. Properties and Values:
   • CSS comprises of properties (what you want to change) and values (how you want to change it). Example: h1 { color: red; font-size: 30px; }
     • color is the property and red is the value.
     • font-size is the property and 30px is the value.
3. The Box Model:
   • Every HTML element is treated as a box by the browser. The box model defines the size of these boxes. It consists of:
     • Content: The actual content inside the element (text, images, etc.)
     • Padding: Space between the content and the border.Border: The border around the padding and content.
     • Margin: Space outside the border between this element and others. Example:
       div { margin: 20px; padding: 10px; border: 1px solid black; }
   • Visualizing the Box Model:
     graph TD;
Margin --> Border;
Border --> Padding;
Padding --> Content;
4. Cascading:
   • CSS stands for Cascading Style Sheets because styles can “cascade” from one rule to another.
   • More specific rules override less specific ones. For example, a style applied directly to an element will override a style applied to the entire page.