Part 1 - Where the magic happens§

Introduction to CSS§

• Open the file discoveringCSS.html in your browser and in your text editor.
• OK. Apparently, there is nothing new here.
• Now, search for the text default.css in the code, and replace it with style1.css.
• Save your edit and refresh your browser. Nice, isn't it?
• Now, you can try to change style1.css in style2.css.

What have we done to change the style of the page?§

We have used this special HTML element: link.

<link rel="stylesheet" href="style1.css">

The link element enables us to "include" other files in our web page.

Here, we have included a Stylesheet writen in CSS that gives instructions to change the look of the page.

What is CSS?§

• CSS means Cascading StyleSheets.
• It is a special language to describe formating rules for web pages.
• For clarity, CSS rules are written in a separate file and are inculded in the HTML document via the link element.

Let's see how CSS works!§

• Open the file style1.css and observe the code.
• As you can see, the code is quite different from HTML code.
• However, you may recognise some HTML elements names.

What is a CSS rule?§

A CSS rule includes is composed of two main elements: a selector, and a set of properties.

• The selector (em in the example below) indicates on which elements the rule will be applied.
• The properties (between brackets) enable to define the expected appearance of the selected element.

em{
   color: green;
   font-size: 20px;
}

For example, this CSS rule means that all the em elements of your web page will be displayed in green and the size of the text will be 20px.

Want to see more examples?§

If you want to have a look at what can be done with CSS, pay a visit to CSS Zen Garden website

On this website, you can see the same web page with many different styles. It is impressive!