Browser Inspector
Last updated
Last updated
Good, you'll need it.
Press f12 or fn + f12 to open up the Dev Tools. On Firefox, this by default opens the Inspector tab, which is where the page's HTML can be seen. Let's use Google's homepage as an example for now.
You'll see 3 windows in the tab (on Firefox at least).
The leftmost window (in the picture above) contains the HTML of the page. It allows to read the HTML, see elements, look at what tags they are using and what attributes they are assigned, and more. It also allows you to look for hidden elements - elements that aren't visible on the page but are present all the same. You can even edit the HTML by double-clicking at a certain part of the code to change its value temporarily and see (in real time) how it affects the contents of the page.
The middle window allows you to see the CSS properties of a selected element on the page. We'll get into CSS in the next section, and there this will be handy since you can inspect the CSS of any element on any webpage, as well as edit styles to see what effect the changes have on the page in real time.
The rightmost window allows you to see the Box model of a selected element, Flexbox of a selected element and Grid layout of the page. When we get into margin and padding later on, the Box model will become a useful visualising tool, but for now we have nothing to do with it.
If you want to select an element on a page, there are 2 ways. The first is to read through the HTML and try and figure out which element is the one you want. This however, is going to be difficult when pages get long and complicated. Just look at this excerpt from the Google homepage:
The second way, and better, is to use the element picker. You'll notice a cursor icon next to the "Inspector" tab title. This is the element picker.
Click on it, and when you move your cursor over the webpage you'll be able to highlight an element. Click on the element or part of the page you wish to look at in detail, and the element will get selected, showing its style and HTML in the Inspector.
Remember how you can temporarily edit the HTML and CSS of the page? Combine that with the element picker, and you have a powerful set of tools to test out CSS styles and HTML elements in real time for development. Here's an example of me playing around on the Google homepage using these tools:
Once you reload the page, all the temporary changes you make are removed and the page is restored to its original, unaltered state.
We've made a pretty nice webpage so far, but it seems... plain. It needs some style, some color, a different font maybe.
In the next section, we'll learn some CSS to add some styling to our page.
