Style sheet

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Transcript Style sheet

HTML
Concepts and Techniques
Fifth Edition
Chapter 8
Creating Style Sheets
Chapter Objectives
• Describe the three different types of Cascading
Style Sheets
• Add an embedded style sheet to a Web page
• Change the margin and link styles using an
embedded style sheet
• Create an external style sheet
Chapter 8: Creating Style Sheets
2
Chapter Objectives
• Change the body margins and background using
an external style sheet
• Change the link decoration and color using an
external style sheet
• Change the font family and size for all
paragraphs using an external style sheet
• Change table styles using an external style sheet
Chapter 8: Creating Style Sheets
3
Chapter Objectives
• Use the <link /> tag to insert a link to an external
style sheet
• Add an inline style sheet to a Web page
• Change the text style of a single paragraph using
an inline style sheet
Chapter 8: Creating Style Sheets
4
Using Style Sheets
• Style - a rule that defines the appearance of an element
on a Web page
• Style sheet – series of rules that defines the style for
Web page or entire Web site
– Alter appearance of Web pages by changing characteristics such
as font family, font size, margins, and link specifications
– Adhere to a common language with set standards and rules
• Cascading Style Sheets (CSS) – language allows Web
developer to write code statements that control the style
of elements on a Web page
Chapter 8: Creating Style Sheets
5
Using Style Sheets
• CSS is not HTML- separate language used to enhance
the display capabilities of HTML
– W3C – defines the specifications for CSS
– Used to add visual elements such as colors, borders,
margins, and font styles to your Web pages
• Makes content look more stylish
• Example: want all text paragraphs indented by five spaces:
– Use style sheet to handle the indenting, rather than coding each
paragraph
– CSS can establish a standard look for all Web pages in
a Web site.
• Using CSS, avoid tedious steps of adding repetitive code to
format the same types of information.
Chapter 8: Creating Style Sheets
6
Using Style Sheets
(3 types of style sheets)
1. Inline style sheet – add a style to an individual HTML
tag (heading or paragraph)
–
Changes specific tag, does not affect other tags in document
2. Embedded style sheet – add style sheet within the
<head> tags of the HTML document
–
defines the style for entire Web page
3. External style sheet (linked) – create a text file that
contains all the styles to be applied
–
–
–
Save file with extension .css
Add link to this external style sheet on any Web page in the Web
site
Most flexibility apply same formats to all pages in Web site
Chapter 8: Creating Style Sheets
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Style Sheet Precedence
• Each style sheet type has a different level of precedence
or priority in relationship to the others.
– Inline – takes precedence over any other style sheet
– Embedded – overrides an external style sheet
• Because style sheets have different levels of precedence,
all three types of style sheets can be used on a single
Web page
– May want some elements of a Web page to match other
Web pages in a site, but also want to vary the look of
certain sections of that web page
• Do this by using the three types of style sheets
Chapter 8: Creating Style Sheets
8
Style Sheet Precedence
Chapter 8: Creating Style Sheets
9
Style Statement Format
• Style statement - a rule that defines the style of an
element on a Web page
– Inline style sheet example:
• <h1 style = “font-family: Arial; font-color: navy”>
• 2 parts of style statement
1. Selector – identifies the page elements (h1)
2. Declaration – identifies how elements should appear
• Everything in quotation marks
• Includes at least one type of style or property
–
For each property, declaration includes a related value, which
specifies display parameters for that specific property.
Chapter 8: Creating Style Sheets
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Inline Style Sheets
1. Inline style sheet – add a style to an individual HTML
tag (heading or paragraph)
–
Changes specific tag, does not affect other tags in document
–
Inline style sheet example:
• <p style = “font-style: italic; font-size: 8pt”>
–
Override both embedded and external style sheets offering
a great amount of flexibility
• Inline style sheets useful when one section of a Web page
needs to have a style different from the rest of the Web page.
Chapter 8: Creating Style Sheets
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Embedded Style Sheets
1. Embedded style sheet – add style sheet within the
<head> tags of the HTML document
–
–
defines the style for entire Web page
End the embedded style sheet by adding an end </style> tag
<style type="text/css">
<!-p {text-indent: 20pt}
a {text-decoration: none;
font-family: Verdana, Garamond;
font-size: 12pt;
color: navy}
a:hover {background: navy;
color: white}
-->
</style>
Chapter 8: Creating Style Sheets
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Embedded Style Sheets
• Style statement using the a selector
– Changes all link states (normal, visited, active)
–
Can define a unique style for each link state by creating 3
separate style statements
•
•
•
–
a:link
a:visited
a:active
a:hover – selector used to define the style of a link when the
mouse pointer points to or hovers over a link.
Chapter 8: Creating Style Sheets
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External Style Sheets
1. External style sheet (linked) – most comprehensive
create a text file that contains all the styles to be applied
–
–
–
•
Save file with extension .css
Add link to this external style sheet on any Web page in the Web
site
Most flexibility apply same formats to all pages in Web site
2 Step Process
1. Create external style sheet
•
Enter all style statements in a text file using Notepad or another text
editor (.css extension) example: styles1.css
2. Link this style sheet onto desired Web pages
•
<link /> tag must be inserted within <head> tags of Web page
–
<link rel=“stylesheet” type=“text/css” href=“styles1.css” />
Chapter 8: Creating Style Sheets
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External Style Sheets (example)
a {text-decoration: none;
color: black}
p {font-family: Verdana, Garamond;
font-size: 11pt}
table {font-family: Verdana, Garamond;
font-size: 10pt;
border-color: #6d6f7b;
border-style: double}
th {background-color: #6d6f7b;
color: white;
text-align: left}
Chapter 8: Creating Style Sheets
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External Style Sheets
1. Format of external style sheet – similar to format of
embedded style sheet
–
external style sheet, does not need <style> tags to start and end
the style sheet
•
–
–
It includes just the style statements
Add link to this external style sheet on any Web page in the Web
site
Most flexibility apply same formats to all pages in Web site
Chapter 8: Creating Style Sheets
16
Adding an Embedded Style Sheet
File name
HTML code
before
modifications
Chapter 8: Creating Style Sheets
17
Text-decoration property settings
•
•
•
•
•
Blink – causes the text to blink on and off
Line-through – places a line through the middle of the
text
Overline – places a line above the text
Underline – places a line below the text
Note: can apply two different text styles to a link by
specifying two text-decoration values, separating the
choices with a space
–
Example: {text-decoration: underline overline}
Chapter 8: Creating Style Sheets
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Adding an Embedded Style Sheet
Start <style> tag
Indicates that
CSS used in
text file
Changes
paragraph style
Beginning
comment line
hides CSS from
browser, if needed
Changes
link style
Sets link
hover style
End comment
line
End <style> tag
Chapter 8: Creating Style Sheets
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Viewing index HTML File
Text set to
12-point
Verdana
menu.html
file
Text indented
20 points
Link hover with white
text on color code
#6d6f7b background
Chapter 8: Creating Style Sheets
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Printing an HTML File
and Web Page
• Print the Web page from the browser
• Click the menu.html - Notepad button on the
taskbar
• Click File on the menu bar and then click Print on
the File menu
• Click the Print button in the Print dialog box to
print the HTML code
Chapter 8: Creating Style Sheets
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Printing menu HTML File
Chapter 8: Creating Style Sheets
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Creating an External Style Sheet
• using Notepad Click File on the menu bar and then click
New
• Enter the CSS code as shown in Table 8–5 on page
HTML 360
• click File on the menu bar and then click Save As. Type
styles1.css in the File name text box. Click the Save
button in the Save As dialog box to save the file as
styles1.css
• Click the File menu, click Print on the File menu, and then
click the Print button in the Print dialog box
Chapter 8: Creating Style Sheets
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Creating an External Style Sheet
Paragraph
style
File saved as
style1.css
Style for all
link states
Table
header
style
Table style
Caption style
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Linking to an External Style Sheet
• Click Notepad button on the taskbar
• Click File on the menu bar, and then click Open on the File
menu
• Navigate to the proper folder. Click the Files of type box arrow,
and then click All Files to show all files in the folder. Click the
contact.html file
• Click the Open button in the Open dialog box
• Highlight the text, <!--Insert link statement here -->, in line 10
• Type <link rel=”stylesheet” type=”text/css”
href=”styles1.css” /> to enter the link to the external
style sheet
Chapter 8: Creating Style Sheets
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Linking to an External Style Sheet
Chapter 8: Creating Style Sheets
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Linking to an External Style Sheet
Link tag
placed
within
<head>
</head>
tags
Link to external
style sheet
Relation
indicates style
sheet is linked
Text indicates
text file uses
CSS code
Chapter 8: Creating Style Sheets
Reference
indicates name
and location of
linked style sheet
27
Working with Classes in Style Sheets
• In some Web sites, might need more control over
the style on a Web page.
– Example: rather than having all paragraphs appear
in the same style, want 1st one to be different.
• To gain more control – define specific elements of
an HTML file as a category, or class.
– Create specific style for each class
» Using classes in style sheets allows applying styles
selectively to HTML tags
» See HTML page 367 in book for examples
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Working with Classes in Style Sheets
• Defining and using Classes (2 Step Process)
1. Any elements that belong to the class are
marked by adding the tag: class=“classname”
•
To define a class that includes any beginning
paragraphs
–
Example: <p class=“beginning”>
2. After naming the classes, use the names in a
selector and define a specific style for the class
•
Example: within the <style> tags in an embedded
or external style sheet – style statement in format:
–
p.beginning {color: red;
font: 20pt}
Chapter 8: Creating Style Sheets
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Adding an Inline Style Sheet
• If necessary, click the welcome.html - Notepad
button on the taskbar so the file welcome.html is
displayed
• Click immediately to the right of the p in the <p>
tag on line 30. Press the SPACEBAR and then
type style=”fontstyle: italic; fontsize: 8pt” to insert the inline style sheet
Chapter 8: Creating Style Sheets
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Adding an Inline Style Sheet
Inline style
sheet added
font-style
property
font-size
property
font-style value
set to italic
font-size
value set
to 8-point
Chapter 8: Creating Style Sheets
31
Viewing and Printing
Framed Web Pages
New style for
links defined
by embedded
style sheet
Paragraph style
defined by external
style sheet that is
linked to pages
Chapter 8: Creating Style Sheets
Last paragraph
style defined by
inline style sheet
32
Chapter Summary
• Describe the three different types of Cascading
Style Sheets
• Add an embedded style sheet to a Web page
• Change the margin and link styles using an
embedded style sheet
• Create an external style sheet
Chapter 8: Creating Style Sheets
33
Chapter Summary
• Change the body margins and background using
an external style sheet
• Change the link decoration and color using an
external style sheet
• Change the font family and size for all
paragraphs using an external style sheet
• Change table styles using an external style sheet
Chapter 8: Creating Style Sheets
34
Chapter Summary
• Use the <link /> tag to insert a link to an external
style sheet
• Add an inline style sheet to a Web page
• Change the text style of a single paragraph using
an inline style sheet
Chapter 8: Creating Style Sheets
35
Homework # 13
• In the Lab 1 page HTML 378-379
• Using External and Internal Styles
• See INF 186 Computer Assignment 13 Web
page for details, hints, and requirements for the
assignment
Project 4: Creating Tables in a Web Site
36
HTML
Concepts and Techniques
Fifth Edition
Chapter 8 Complete
Creating Style Sheets