Introduction to CSS Lab

Learning Goals

  • Link an external CSS file
  • Write CSS rules to style HTML

Introduction

In this lab, we will be adding style to our index.html page by linking an external CSS file. If you open index.html in the browser (by either opening the file with Google Chrome or running httpserver on the Learn IDE), you will see basic HTML that has been provided. The website emulates a basic Real Estate website (the links on it have been disabled, we will be working with only the basic index.html landing page).

As you can see, our basic page is rather lackluster. This is where you come in! You will be adding CSS, using selectors, to jazz the page up. All of our CSS should be written in style.css.

Link an External CSS File

As usual, we need to make sure our HTML is loading our style sheet.

We have two options:

  1. Write CSS rules inside of a <style> tag ("internal CSS"), which tells HTML "Hey, I want to define some CSS styling here
  2. Write CSS rules in an external file that is specified with the <link> tag ("external CSS").

In our case, we want to provide a link to our style sheet, instead of writing all of our CSS code directly in the <style> tag. This allows us to only have to write styles for the entire site once, instead of repeating every <style> element on every page. A common workflow is to see developers work on CSS inside of the <style> tag until their styling is done. At that point, they move it to their external file and remove the <style> element from the HTML page. Feel free to try it out!

In index.html, provide a <link> tag which correctly sources the CSS file located in this directory. The <link> tag will link to our file with an href attribute, like so:

<link rel="stylesheet" href="relative path to CSS file">

Links to style sheets should go at the end of the <head> section! Make sure you provide a relative path to the style sheet.

Now, what is a relative path? You could write href="style.css" and the content of style.css would change your index.html file. But we want to teach you to require external resources (like CSS or JavaScript) by using relative paths. Relative paths make it crystal clear which file is being used. Relative paths start with ./ which means "from the directory I am currently in." So, when we use link to associate with a style sheet and we write href="./style.css" we're saying: "From the directory in which I, the index.html file live, look for a file called style.css and use it. This pattern will help you and other developers remove any possible confusion.

Hint: Try adding the following temporarily to your style.css file to test if your linked CSS is working:

h1 {
  color: red;
}

If you see your <h1> change to red, you've linked your style sheet correctly! Don't forget to delete it once you have your link working.

Write CSS Rules to Style HTML

For this exercise, we are going to be transforming our base HTML into a more exciting version using CSS.

It is important to note that there are many ways to go about transforming the HTML with CSS to match the end product. For this lesson, we will provide you with general guidance in one way of getting to the desired view by adding to the style.css. Ultimately, the goal is to have your website look like the finished product whatever way works the best for you.

Note: If you are having trouble finding the specific CSS property you need to get a specific visual outcome, use your Google-Fu with queries such as: "CSS center text within div".

In following the guidelines, you should be referencing the index.html to find the appropriate tags/IDs that we will use as selectors in our style.css file. Don't forget: you can use the Chrome Inspector Tool (cmd + shift + C on Mac) to inspect specific elements of the DOM (and make trial changes to their CSS) in the browser.

What We Have

What We Want

Deliverables

  • Update the header: the text is a little wonky being aligned on the left like that. Provide a property that aligns it in the center instead

  • Center our image: We only have one image on the page and we would like it centered!

  • Jazz up our navigation links: Let's center all of our nav links as well. Give all of the <a> tags within our navbar padding of 10px on their left and right sides. In addition, change their background color to something of your choosing. We chose grey!

  • Our image caption needs work: Let's shrink that font size down and make sure it is centered.

  • Update the text block: Wouldn't it look nicer if our text was centered as well? Our image is about 900px wide, so let's give all our <p> within #featured-property a hard width of 800px and center the text in there.

  • Make our #details section horizontal: The details section could go nicely as a footer to the page, instead of a vertical list. Change its display value to block and make sure each of the <div>s is floating to the left.

  • As a finishing touch: Let's clean up the <div>s at the bottom of the page. All of them should have the same background color, centered text, and occupy 25% of the width of the bottom row (since we have 4 divs).

Conclusion

CSS allows many avenues to the same goal. The important takeaway is to experiment and become familiar with the commonly used rules. This will enable you to identify what properties will get you to which end result the quickest.

You will find that even years into your career as a front end developer, you will be referencing basic CSS documentation. This is to be expected!. To be comfortable quickly finding the property/value you are looking for online is the most important skill set you can develop right now. Memorization is for machines, adaptation is for humans!