Add a link with the text "Open documentation" pointing to https://developer.mozilla.org that opens in a new tab. Because it opens a new tab, protect the original page with rel="noopener noreferrer".
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HTML Tutorial · HTML Basics
These 10 tasks go with the HTML Elements & Attributes chapter. 5 of them ask you to build something small from scratch; 5 give you code that is already broken and ask you to work out why. Set aside about 110 minutes for the whole set, though you can do them in any order.
Nothing here is marked by a person. When you press Submit, the editor checks your code against the points listed under each task and tells you straight away what passed and what didn't (you need a free account to submit). If you get stuck, there are hints, and a worked solution once you've had a go. The first 2 tasks are free; the rest are part of the practice plan.
If it's been a while since you read the chapter, here is how it starts: “HTML pages are built using elements — the building blocks of a web page. Each element defines a specific part of the content such as headings, paragraphs, images, or links. Elements often include attributes that provide extra information about that element.” .
1.Open a new tab safelyexercise · easy · 10 min
Add a link with the text "Open documentation" pointing to https://developer.mozilla.org that opens in a new tab. Because it opens a new tab, protect the original page with rel="noopener noreferrer".
Passes when: Open the link in a new tab; Add rel="noopener noreferrer" for security.
2.Use void elements correctlyexercise · easy · 10 min · practice plan
Add a horizontal rule to separate two sections, and use a line break inside the second paragraph to put an address on its own line.
Passes when: Add an <hr> between the sections; Add a <br> inside the address paragraph.
3.Disable a button with a boolean attributeexercise · easy · 10 min · practice plan
Add a "Submit" button that is disabled until the form is valid — give it the disabled attribute.
Passes when: Add the disabled attribute.
4.Add a tooltip with the title attributeexercise · easy · 10 min · practice plan
Give the abbreviation "HTML" a title attribute containing "HyperText Markup Language" so hovering shows the full term.
Passes when: Add the tooltip text.
5.Combine multiple attributes on one elementexercise · medium · 15 min · practice plan
Build a submit button with three attributes: type="submit", id="submit-btn", and class="btn-primary".
Passes when: Set type="submit"; Set id="submit-btn"; Set class="btn-primary".
6.Fix the unsafe new-tab linkbug fix · easy · 10 min
This link opens in a new tab but is missing rel="noopener noreferrer", leaving the original page exposed. Add it.
Passes when: Add the missing rel attribute.
7.Fix the missing void elementsbug fix · easy · 10 min · practice plan
This page has no thematic break between the two sections, and the address runs onto one line. Add an <hr> between the paragraphs, and a <br> inside the address to put the city on its own line.
Passes when: Add an <hr> between the sections; Add a <br> inside the address paragraph.
8.Fix the misleading disabled attributebug fix · easy · 10 min · practice plan
This button uses disabled="false", but any value — even "false" — still makes a boolean attribute true. Remove the ="false" so the attribute reads as a clean, valueless disabled.
Passes when: Use a bare disabled attribute, not disabled="false".
9.Fix the garbled tooltip textbug fix · easy · 10 min · practice plan
The title attribute on this abbreviation is garbled. Fix it to read exactly "HyperText Markup Language".
Passes when: Fix the tooltip text.
10.Fix the button's mistyped attributesbug fix · medium · 15 min · practice plan
This button's id and class values have typos. Fix id to "submit-btn" and class to "btn-primary".
Passes when: Fix id to "submit-btn"; Fix class to "btn-primary".
Between them these tasks cover HTML Elements & Attributes.
Looking for a different chapter? See every practice set, or switch to the interview theory questions.