# How This Course Works

How CSS in Depth works on ask-codey.com, from reading a lesson and running its exercise checks to mastering a skill and passing a module assessment.

Novice · CSS · Web Development · Updated October 30, 2026

## After this lesson you can

- Describe how the parts of CSS in Depth fit together: lessons, Check yourself, practice, chapter checks and module assessments

## Key takeaways

- CSS in Depth has six modules. Each one ends with a project of its own, and the course ends with a complete site.
- Skills are short "you can do this" statements. They are what the questions test and what your progress counts.
- An exercise is done when every check passes. You run the checks yourself with npm test.
- Chapter checks are practice you can take as often as you like. A module assessment passes at 80%, with three tries a day.
- Covered counts the lessons you've finished; Mastered counts the skills you've shown you know, with three clean answers to questions that come at each skill from at least two different angles.

This course is self-study: you go at your own pace, and the course itself tells you how you're doing. A few minutes here now saves guessing later, because every chapter works the same way. Here is what the course is made of, and how to get the most from each part.

## The shape of the course

| Part | What it is |
|---|---|
| **Module** | A big stage of the course. This course has six: Your First Styled Page, The Cascade and Selectors, Layout, Responsive Design, Design with CSS, and CSS at Scale. |
| **Chapter** | One subject, such as *Flexbox* or *Custom Properties and Themes*. |
| **Topic** | A group of lessons inside a chapter. |
| **Lesson** | One idea, explained with small examples you can try in your own browser. |
| **Project** | The end of each module: a site of your own, built with everything the module taught. The course ends with a complete site for a small business. |

Each lesson has a **level** from 1 to 4: meeting an idea is level 1, working with it level 2, building with it level 3, and the advanced end level 4. A level says how deep a lesson goes into its subject, not how far into the course it is.

## Skills: what you'll be able to do

Most lessons start by listing their **skills**: short "you can do this" statements, such as *Name the parts of a CSS rule: selector, declaration, property and value*. Skills are what the questions test, and what your progress counts.

## Check yourself

Near the end of a lesson, a **Check yourself** block asks one to three short questions about what you just read, then shows you the answer and why. Use them as a quick self-test: if you get one wrong, that's useful news, not a failure. Read the explanation, look back at the lesson, and carry on.

## Exercises, and their checks

Lessons whose titles start with **Exercise:** give you a small project: a page that's ready, a stylesheet for you to write, and **checks**, a small program that reads your files and says whether each part is doing its job. You download the exercise code, open it in VS Code, and work with the page open in your browser. In VS Code's terminal you run `npm install` once, then `npm test` as often as you like. When every check passes, you're done.

The checks can tell whether the prices are bold and the right color, but not whether the page looks good. That part is yours: each exercise has a short checklist for looking at the page in the browser. Exercises are where reading turns into skill, so don't skip them.

## Chapter checks and module assessments

- A **chapter check** is a short quiz on the chapter's skills. Take it whenever you like, as often as you like: it's practice, and it tells you what to review.
- A **module assessment** ends each module. **80% passes**. You get three tries a day, then a 24-hour rest before the next three.

Every attempt draws different questions, so a retake is a fair new try, not a memory test. Most learners take an assessment more than once.

## Covered and Mastered

When you're signed in, the course keeps two separate records of your progress:

- **Covered:** the lessons you've finished.
- **Mastered:** the skills and key terms you've shown you know. A skill is mastered when you answer three different questions about it cleanly, meaning right the first time and without a hint, and those questions come at it from at least two different angles. For a skill such as *center a box with flexbox*, one question might ask which rule centers it, and another might show you a page where the box isn't centered and ask what's wrong. Answering from two angles shows you understand the skill, not that you remember one answer. A later miss drops it back, so mastery stays honest.

Reading every lesson doesn't mean you know it, and the course never pretends it does. That's why the two are kept apart.

## Who gets what

- **Everyone**, signed in or not, can read every lesson and answer its Check yourself questions.
- **Signed in**, your answers count toward your skills, and you can tick lessons as done.
- **With Premium, or if you own this course,** you also get course progress on every page, the chapter checks, the module assessments, and the **Certificate of Completion**: every lesson covered and every module assessment passed.

## A good rhythm

1. Read a lesson, and try its examples in your own browser.
2. Answer its Check yourself questions.
3. Do the exercise at the end of each chapter, and run its checks until they all pass.
4. Take the chapter check, and review the skills it points to.
5. When a module's skills are mastered, take its assessment, then build the module's project and put it online.

**Try it.** Look at this chapter's list of lessons. Find the exercise lesson at the end, and the chapter check after it: that's the rhythm every chapter follows.

## Check yourself

1 question to try on the lesson page.

## So what

The course is built so you always know where you stand: what you've read, what you've mastered, and what to practice next.

Source: https://www.ask-codey.com/lessons/css-how-this-course-works