Fixing buggy responsive CSS Zen subtheme

Question

I have a responsive Drupal Zen subtheme that I hacked together about a year & a half ago from some CSS & HTML that a non-Drupal designer handed off to me for my website. I've known that in certain layouts, it is buggy, and needs to be fixed, but I just haven't gotten around to it. After repeatedly reaching out to a local Drupal developer (and offering to pay him), I've gotten tired of waiting, and just need to fix this thing.

My bounce rate for folks on mobile devices is awful.

The URL is http://developcents.com. The homepage looks decent on any device. Internal pages need a lot of help, though, when viewed in certain screen sizes (including mobile devices). Let's use http://developcents.com/blog as an example.

In the below scenario, my question is not how to find the CSS files themselves. Rather, my question is, how can I find the necessary CSS settings using Firebug Lite, so that I can debug the CSS through my browser, instead of having to manually update each CSS file every time I want to test a change?

I can't find the actual CSS-styled divs, blocks, etc... causing the layout to break under certain dimensions. I know how to find, and edit, the CSS within the CSS panel, but I can't track down the specific CSS in this instance.

Additionally, as a secondary question, if you want to provide pointers on what I actually need to change, then please be my guest! But if you point me in the right direction on how I can go figure it out myself, that's fine too. :)

Let's get on to the scenario (which you can easily see by testing it yourself):

When I resize my browser window down to a certain size, the links & tweets section in the left sidebar move over to the right, so that the left side of the navbar aligns with the right side of the header area, while the content spans the full width of the page, except for the left margin, which stays in place but gets wider. Basically everything below the header gets screwed up, and it's easier to see the problems than explain them (so go test it).

Using Firebug Lite in Chrome, I can't seem to find the left margin for the "main" content area (see this screenshot clearly indicating the yellow margin), nor can I find the CSS for the navbar / tweets block (which I presume is some sort of float).

Answer 1

To modify the CSS within Firebug or Firebug Lite just select an element inside the HTML panel or inspect it via its inspector. Inside the Style side panel you'll see all CSS rules applying to the element.

Clicking the name or the value of a CSS property opens an inline editor to allow editing it.

On the right side of each rule you'll see the name of the style sheet, which contains the rule. Hovering it displays you the full URL and clicking it allows you to inspect it within the CSS panel.

You can also edit the styles directly within the CSS panel, which lists all style sheets available on the page.

Note: The changes you do there are not permament, i.e. on the next page reload they are gone! To make permanent changes you need to edit the files on the server.

Also note that I'm referring to the panels within Firebug. The panels within Firebug Lite basically work the same, though may look and work a little bit different. Furthermore Firebug Lite is not maintained anymore, so there's no guarantee that everything is working as expected.