Full disclosure, I've worked at Wolfram in the design department for decades and know the power of the Wolfram Language but I haven't broken through to use it to solve my own problems even though I know there are tons of things I do in my daily life that the Wolfram Language could help me do better. In this case, after decades, I'm converting my personal websites to a mobile friendly template. I'm looking at about 3,000 html documents that need certain elements removed and replaced with something else. I've seen coworkers use Mathematica for complex find and replace queries and thought - wow - I know WL can save me days and days of cut and paste. So here's my first post ever to our community.

Is there a way I can have Mathematica replace any width and height attributes found in an html document with my new class="responsive-image" tag? So for example "width="xxx" height="xxx" needs replaced with "class="responsive-image"" in 3,000 documents. The xxx can vary which is why Dreamweaver's simple find and replace logic isn't enough. That's the info - let's give this a try. Thanks.