Iconic
Font Awesome, the iconic font and CSS toolkit
What Theme? - Discover what theme is used on your favorite website
Material Design Lite
wwwhere
Responsive Web Design just got Easier with the Responsive Grid System
HTML5 Boilerplate: The web’s most popular front-end template
Create beautiful photo narratives - Exposure
Best Web Gallery
Gridulator: Make pixel grids, lickety-split
resizeMyBrowser
Dirty Markup · Tidy up your HTML, CSS, and JavaScript code
Font Awesome Cheatsheet
Call-to-Action Button Generator - Design buttons & download as CSS PNG
Website builder, in browser web design, CMS & hosting | Webydo
Specifics on CSS Specificity | CSS-Tricks
Free Website Builder | Make a Free Website - IM Creator
Google Web Designer
A List Apart: For People Who Make Websites