CSS guide for a fast, high-performance site

Have you ever wondered what tool web designers use to shape the aesthetics of websites? Today we introduce you to CSS, the language that governs the style, accessibility and functionality of web pages, ensuring a smooth and engaging user experience.

CSS stands for Cascading Style Sheets. It is the style language that allows web designers to define the layout and graphic appearance of a site, separating the HTML content from its visual performance.

Without CSS, an HTML page would appear as a simple block of text, with no formatting and cluttered images.

This language allows a uniform style to be applied to the graphic elements of the site, ensuring consistency and facilitating design management.

One of the main features of CSS is the possibility of using an external style sheet, which makes it possible to:

• Disconnect HTML content from formatting, improving site management and maintenance.
• Flexibly and precisely customise every aesthetic aspect, working on both text and block elements.
• Make the site responsive, adapting it to any device and resolution.

Like any language, CSS follows rules that are interpreted by browsers to apply styles to page elements.

Here are the key concepts to know in order to master it:

• Cascading: style rules are applied in order of priority, like a ‘waterfall’.
• Selectors: identify the HTML elements to which style rules are to be applied.
• Properties: these are the characteristics that can be modified (colour, margin, border, etc.).
• Values: specify the settings for each property (size, hue, spacing, etc.).
• Declarations: assign a value to a property.
• Blocks of Declarations: set of declarations enclosed in curly brackets.
• Style Rules: combine selectors and declaration blocks.
• Comments: notes in the code to describe the operation of an element, not visible to users.
• Style Sheets: collection of CSS rules applied to one or more web pages.

In addition to these concepts, it is essential to know the 3 ways of integrating CSS into a web page:

• Inline styles: applied directly to HTML elements. They have the highest priority, but make the code less readable and difficult to maintain.
• Internal style sheets: defined within a specific HTML page, useful for targeted customisation.
• External style sheets: separate and linked CSS files, ideal for ensuring visual consistency throughout the site and simplifying code management.

The use of CSS offers numerous advantages:

• Clearer and more organised code, making it easier to manage the site.
• Consistent design on all pages.
• Simplified maintenance, reducing updating work.
• Improved accessibility and usability, thanks to adaptable layouts.
• Better performance, with lighter pages and reduced loading times.
• Attractive visual effects for a more engaging user experience.

A well-designed site is intuitive and encourages interaction with users. With CSS, you can make navigation smooth and pleasant, improving audience engagement and satisfaction.