Glad I could help out!
If you haven’t already checked it out, the Webflow University has a ton of great resources to run through to get you familiar with things. Alternatively I’d also recommend taking some time to get comfortable with how to structure HTML and write CSS given that Webflow is grounded in the structure of “traditional” web development. Learning how to manual writing code will help you understand how to best organize your future projects within Webflow and ensure you’re using the platform as a tool instead of a crutch. I know it can seem pretty daunting, and I still learn new things even though I started coding in grade school, but it’s awesome seeing more and more people explore web development with help of Webflow.
As far as your most recent issue, your footer symbol is set to have a background color for the 1440px and up breakpoint. Removing this by clicking the label and choosing “Rest” (or alternatively Alt+Clicking the label) will revert it back to your transparent color used across the other breakpoints.
A quick way to troubleshoot issues like this is to look for the blue highlighted labels within the style panel as this indicates that it’s been overwritten for that particular breakpoint. All of the orange highlighted labels indicate that a style was overwritten from the default but not modified on that given breakpoint yet.
You can always click on these colored labels to see which breakpoint/class that specific style is being inherited from which can help make sense of more complex relationships - especially when it comes to sub-classes.