1. Unit 1: Web Fundamentals
Lesson 7: Introduction to CSS
August 21, 2013

2. Lesson 7: Introduction to CSS
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Introduction
to HTML
Learning to
Use HTML
HTML and
Email
History and
Future of the
Web
HTML and
Forms
Search
Engine
Optimization
Learning to
Use CSS
Introduction
to CSS
Reusing
Code
3 Ways to
Use CSS
Separation of
Concerns
Launching
Your Own
Website
Lesson 1 Lesson 2 Lesson 3 Lesson 4
Lesson 8 Lesson 7 Lesson 6 Lesson 5
Lesson 9 Lesson 10 Lesson 11 Lesson 12
Build understanding Develop skills

3. Recap of Lessons 1-6 (I)
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• HTML is very important and is used in everything from websites to
email messages to sending data with forms
• HTML files are easy to create – no harder than writing a Word
document

4. Recap of Lessons 1-6 (II)
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• We can add images and video to our HTML by using tags
• Websites such as YouTube will even give us the HTML code to
make embedding content easy

5. Recap of Lessons 1-6 (III)
5
• Forms help us send information to a server whenever we sign in,
search, or post on Facebook
• Meta tags allow us to tell potential visitors what our website is about
• Search engine optimization can help our site rank higher when
websites like Google or Yahoo show search results
This is the meta description tag

6. We’ve done HTML – now let’s look at CSS
• We have seen why HTML is important, but CSS is just as useful
• When HTML provides the structure for a page, CSS lets us make it
look pretty
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HTML is the
structure/skeleton
CSS is the
presentation/clothing
jQuery/Javascript is
the action/movement

7. What would websites look like without CSS? (I)
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Facebook Facebook without CSS

8. What would websites look like without CSS? (II)
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Pixar Pixar without CSS

9. What would websites look like without CSS? (III)
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Google Google without CSS
• Even Google doesn’t look good without CSS!

10. One website can change a LOT when styled with
different CSS
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• Believe it or not, but the two webpages below were written using
identical HTML code
• The only difference between them is in their CSS styling!

11. Restyling the Guardian (I)
1. Last time, we edited the HTML code of the Guardian website. This
time, we’ll edit the Guardian’s CSS code. Open up your Chrome
web browser and navigate to www.theguardian.com/uk
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12. Restyling the Guardian (II)
2. Right click on the white background and click ‘Inspect Element’
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‘Inspect
Element’

13. Restyling the Guardian (III)
3. Next to the HTML code we looked at last time, you should see a
small box in the lower right. Scroll halfway down until you see
‘background-color’
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14. Restyling the Guardian (IV)
4. Click the box next to ‘white’, and then select a color in the window
that appears
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Click here

15. Restyling the Guardian (V)
5. Now the Guardian has a background color!
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16. Restyling the Guardian (VI)
6. However, can you guess what happens when we refresh the page?
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Refresh

17. Restyling the Guardian (VII)
7. The background color went back to white!
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18. How does the internet work – Take #2 (I)
• To understand why our changes disappeared, we need to revisit
how the internet works
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ISP
Facebook
server
Amazon
server
Youtube
server
DNS
Router

19. How does the internet work – Take #2 (III)
• Originally, we said that the Youtube server was sending Andy Murray
the webpage files he requested
• But the server is sending more than just the HTML files – it’s also
sending CSS files for the page
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Youtube
server

20. How does the internet work – Take #2 (IV)
• If Andy were to receive just the HTML
files, he would see a simple version of
the site
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21. How does the internet work – Take #2 (V)
• If Andy were to receive just the HTML
files, he would see a simple version of
the site
• If he received both HTML and CSS, he
would see the full website
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22. How does the internet work – Take #2 (VI)
• If Andy were to receive just the HTML
files, he would see a simple version of
the site
• If he received both HTML and CSS, he
would see the full website
• If he only received the CSS files, he
would not see the website at all. You
cannot add style to a page that has no
structure!
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23. Summary (I)
• CSS is just as important as HTML because it allows us to style a
page to make it look pretty
• Changing the CSS of a site can make a big difference!
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24. Summary (II)
• It’s just as easy to edit CSS as it is to revise HTML
• A server actually sends TWO files when you request a webpage –
HTML and CSS
• You need both to see the full version of the website
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25. What to do on your own
1. Go to URL to complete the Codecademy course online
2. Do the practice set on the material learned
1. Take the follow-up quiz to test your understanding
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