I've done web development for the past 16 years, most of it focused on front-end stuff,e.g. classic ASP, ASP.Net, jQuery, CSS, HTML, JS.
The "pixel-perfect" is likely in relation to being able to take a mock up and write the HTML and CSS that renders it perfectly in all browsers(IE, Firefox, Chrome, and Safari) on all OS(Linux, Windows, OS X) as well as mobile possibly. The field keeps growing so it is worth noting how broad this can be at times.
I've had various interviews since different companies could require different things. Some places like Microsoft or Amazon would ask for whiteboard coding problems while other companies may just do standard questions to see what I know as well as to see how I handle things I may not know. Sometimes I'll get coding questions and sometimes not. Often there will be questions about my work history and what I did at various companies in various capacities.
Thus, I would suggest reviewing a white board problem like reversing a string or building a priority queue where the key is to focus on the communication you have in explaining what you are doing and covering various bases as one point.
Review your work history to find a few stories for some of the classic questions:
When a project was in jeopardy of being done on time, what did you do to save the project?
When you had a disagreement with a co-worker how was that handled?
When a customer has unrealistic expectations, what do you do?
Which technologies are listed on your resume that you may explain your experience using?
For those where you do have experience, that is useful to remember while in other cases it may be more of a hypothetical.
Last but not least, remember to have some questions for the company to show you are interested in the position as well as how they work. Do they use tools you already know or would it be all new stuff? Do they use processes you've seen already? Are they expecting you to do graphics and functionality or focus more on one over the other? Will there be work on databases? Are all back-end jobs handled by others or could you work on that if you wanted as there could be cases of high workload or the back-end people go on vacation and stuff has to get done where you may get to step up? There are lots of questions that make sense to ask to get an idea of how do they work that make sense as good questions to get an idea of what the job would look like as well as get the interviewer to picture you in the position.