HTML5 COMMENTS & CSS CHAPTER 8
HTML comments are not displayed in the browser, but they can
help document your HTML source code.
HTML Comment Tags
You can add comments to your HTML source by using the
following syntax:
<!--
Write your comments here -->
With comments you can place notifications and reminders in
your HTML:
<!DOCTYPE html>
<html>
<body>
<!-- This is a comment -->
<p>This is a paragraph.</p>
<!-- Comments are not displayed in the browser -->
</body>
</html>
OUTPUT
This is a paragraph.
Comments are also great for debugging HTML, because you can
comment out HTML lines of code, one at a time, to search for errors:
<!DOCTYPE html>
<html>
<body>
<!-- Do not display this at the moment
<img border="0" src="pic_trulli.jpg"
alt="Trulli">
-->
</body>
HTML Styles – CSS
Styling HTML
with CSS
CSS stands for Cascading Style Sheets.
CSS describes how HTML
elements are to be displayed on screen, paper, or in other media.
CSS saves a lot of
work. It can control the layout of multiple web pages all at once.
CSS can be added to HTML
elements in 3 ways:
- Inline - by using the style attribute in HTML
elements
- Internal - by using a <style> element in the <head> section
- External - by using an external CSS file
The most common way to add
CSS, is to keep the styles in separate CSS files. However, here we will use
inline and internal styling, because this is easier to demonstrate, and easier
for you to try it yourself.
Tip: You can learn much more about CSS in our CSS Tutorial.
Inline CSS
An inline CSS is used to apply
a unique style to a single HTML element.
An inline CSS uses the style
attribute of an HTML element.
This example sets the text
color of the <h1> element to
blue:
<!DOCTYPE
html>
<html>
<body>
<h1
style="color:blue;">This is a Blue Heading</h1>
</body>
</html>
OUTPUT
This is a Blue Heading
Internal CSS
An internal CSS is used to
define a style for a single HTML page.
An internal CSS is defined in
the <head> section of an HTML page,
within a <style> element:
<!DOCTYPE
html>
<html>
<head>
<style>
body
{background-color: powderblue;}
h1 {color: blue;}
p {color: red;}
</style>
</head>
<body>
<h1>This is a
heading</h1>
<p>This is a
paragraph.</p>
</body>
</html>
OUTPUT
This is a heading
This is a paragraph.
External CSS
An external style sheet is used to define the style for many HTML pages.
With an external style sheet,
you can change the look of an entire web site, by changing one file!
To use an external style
sheet, add a link to it in the <head> section of the HTML page:
<!DOCTYPE
html>
<html>
<head>
<link rel="stylesheet"
href="styles.css">
</head>
<body>
<h1>This is a
heading</h1>
<p>This is a
paragraph.</p>
</body>
</html>
OUTPUT
This is a heading
This is a paragraph.
An external style sheet can be
written in any text editor. The file must not contain any HTML code, and must
be saved with a .css extension.
Here is how the
"styles.css" looks:
body {
background-color: powderblue;
}
h1 {
color: blue;
}
p {
color: red;
}
background-color: powderblue;
}
h1 {
color: blue;
}
p {
color: red;
}
CSS Fonts
The CSS color property defines the text color to be used.
The CSS font-family property defines the font to be used.
The CSS font-size property defines the text size to be used.
<!DOCTYPE
html>
<html>
<head>
<style>
h1 {
color: blue;
font-family: verdana;
font-size: 300%;
}
p {
color: red;
font-family: courier;
font-size: 160%;
}
</style>
</head>
<body>
<h1>This is a
heading</h1>
<p>This is a
paragraph.</p>
</body>
</html>
OUTPUT
This is a heading
This is a paragraph.
CSS Border
The CSS border property
defines a border around an HTML element:
<!DOCTYPE
html>
<html>
<head>
<style>
p {
border: 1px solid powderblue;
}
</style>
</head>
<body>
<h1>This is a
heading</h1>
<p>This is a
paragraph.</p>
<p>This is a
paragraph.</p>
<p>This is a
paragraph.</p>
</body>
</html>
This is a heading
This is a
paragraph.
This is a
paragraph.
This is a
paragraph.
CSS Padding
The CSS padding property
defines a padding (space) between the text and the border:
<!DOCTYPE
html>
<html>
<head>
<style>
p {
border: 1px solid powderblue;
padding: 30px;
}
</style>
</head>
<body>
<h1>This is a
heading</h1>
<p>This is a
paragraph.</p>
<p>This is a
paragraph.</p>
<p>This is a
paragraph.</p>
</body>
</html>
OUTPUT
This is a heading
This is a paragraph.
This is a paragraph.
This is a paragraph.
CSS Margin
The CSS margin property
defines a margin (space) outside the border:
<!DOCTYPE
html>
<html>
<head>
<style>
p {
border: 1px solid powderblue;
margin: 50px;
}
</style>
</head>
<body>
<h1>This is a
heading</h1>
<p>This is a
paragraph.</p>
<p>This is a
paragraph.</p>
<p>This is a
paragraph.</p>
</body>
</html>
OUTPUT
This is a heading
This is a
paragraph.
This is a
paragraph.
This is a
paragraph.
The id
Attribute
To define a specific style for
one special element, add an id attribute to the element:
<p id="p01">I am
different</p>
then define a style for the
element with the specific id:
<!DOCTYPE
html>
<html>
<head>
<style>
#p01 {
color: blue;}
</style>
</head>
<body>
<p>This is a
paragraph.</p>
<p>This is a
paragraph.</p>
<p
id="p01">I am different.</p>
</body>
</html>
OUTPUT
This is a
paragraph.
This is a
paragraph.
I am different.
Note: The id of an element should be unique within a page,
so the id selector is used to select one unique element!
The class
Attribute
To define a style for special
types of elements, add a class attribute to the element:
<p class="error">I am
different</p>
then define a style for the
elements with the specific class:
<!DOCTYPE html><html>
<head>
<style>
p.error {
color: red;
}
</style>
</head>
<body>
<p>This is a paragraph.</p>
<p>This is a paragraph.</p>
<p class="error">I am different.</p>
<p>This is a paragraph.</p>
<p class="error">I am different too.</p>
</body>
</html>
OUTPUT
This is a
paragraph.
This is a
paragraph.
I am different.
This is a
paragraph.
I am different too.
External
References
External style sheets can be referenced with a full URL or with a
path relative to the current web page.
This example uses a full URL to link to a style sheet:
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet"
href="https://www.w3schools.com/html/styles.css">
</head>
<body>
<h1>This is a heading</h1>
<p>This is a paragraph.</p>
</body>
</html>
OUTPUT
This is a heading
This is a paragraph.
This example links to a style sheet located in
the html folder on the current web site:
<link rel="stylesheet" href="/html/styles.css">
This example links to a style sheet located in
the same folder as the current page:
<link rel="stylesheet" href="styles.css">
