css-tricks (css-tricks.com) is, quoting their own about page, "a cheezy name." It's a site that provides 'tricks', analysis, detailed descriptions, and more of web design and the industry at large. It's been a source of very valuable education for novice web developers since 2007.
I've utilized their articles more times than I can count. It's been a constant resource in designing this site and other projects. The tutorials are beautifully in-depth, and the design itself is inspiring, especially in its use of space. It was a large inspiration for the current cass-e.net theme! The article I first found it via was its flexbox reference, which I still pull up for new products to this day.
I highly recommend checking it out for its beautiful design, and its incredible library of articles and reference.
When I first started interacting with css-tricks, its design was v16 (the current theme is v17). I found it notable for featuring a vertical nav bar, very readable type, and very efficient use of space. Many responsive designs result in giant unused gulfs of space to the left and right of page content - something I wanted to avoid. It became a valuable source of inspiration. css-tricks has an archive of previous themes here, which inspired me to host my own.
I held off posting about it for a long time - in equal parts because I was a little bit mad about the quality of it, and because I suspected everyone already knew about it. I referred a friend having trouble to the site recently, and when I saw how much it helped them, I reconsidered.