CSS (Cascading Style Sheets) is a fundamental technology used in web development to control the appearance of HTML elements on a webpage. It allows developers to separate content from design by defining styles, such as colors, fonts, layouts, and spacing, in a separate file or within a <style> tag in an HTML document.
Key concepts in CSS include:
Selectors: These target HTML elements to apply styles. Common selectors include element selectors (e.g.,
pfor paragraphs), class selectors (e.g.,.classname), and ID selectors (e.g.,#idname).Properties and Values: CSS uses properties (like
color,font-size,margin) to define the aspects of the element to be styled, and values to specify the particular style (e.g.,color: blue;).Box Model: Every HTML element is considered as a box with four components—content, padding, border, and margin. Understanding the box model is crucial for controlling layout and spacing.
Responsive Design: CSS enables responsive web design through media queries, which allow styles to change based on the screen size or device characteristics, ensuring a consistent user experience across different devices.
Cascading and Specificity: CSS rules can cascade, meaning multiple styles can apply to an element. Specificity determines which rules take precedence, allowing for fine control over how styles are applied.
With these basics, developers can create visually appealing, responsive, and well-structured websites.
