You should do the four recommended exercises. Do the optional exercises if you want more practice.
Exercises in the Explore section are more challenging. You may need to use HTML and CSS we haven’t covered yet. Get ready to Google!
Create a page that looks like this, using CSS styles:

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Create a page that looks like this, using CSS styles:

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Create a page that looks like this, using CSS styles:

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Create a page that looks like this, using CSS styles:

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Create a page that looks like this:

Match the colors approximately. Use any sans serif font. Use at least one CSS class (I used more in my solution).
I made my browser narrow to make the screenshot above, so I could fit it in this page. You don’t need to have this width.
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These challenging exercises may use HTML and CSS that you haven’t seen yet. Get ready to Google!
Make a page that looks like this:

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Make a page like this:

Do not use a graphics program! Use HTML and CSS only.
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Make a page like this:

Type the text into your HTML in the normal way! Copy-and-paste this into your solution:
Hey!
This is reversed!
Flip it around, willya, buddy?
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Make a page showing the YouTube video, “Potter Puppet Pals: The Mysterious Ticking Noise.” Your page should look like this:

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