Sassy-validation is described as 'Sass data type validation library' and is an app in the Development category. There are more than 50 alternatives to Sassy-validation for a variety of platforms, including Online / Web-based, Self-Hosted solutions, Mac, Windows and Linux. The best alternative is Bootstrap, which is both free and Open Source. Other great apps like Sassy-validation are Materialize (Free, Open Source), UIkit (Free, Open Source), Semantic UI (Free, Open Source) and Foundation (Free, Open Source).
400+ material UI elements, 600+ material icons, 74 CSS animations, SASS files, templates, tutorials and many more. Free for personal and commercial use. Trusted by 1 000 000 + developers & designers. Used by such companies as Nike, Samsung, Amazon, Ikea, and Sony.
960 grid system with 12 columns for Responsive Web Design. PSD file which has the 960 grid setup for you based on 32px gutters/margins. Offsetting columns - if you need to position a column over by say 2 columns. Four main media queries: 1. browsers over 960px
Set column and gutter widths, choose the number of columns, and switch between pixels and percentages. All without any .grid_x classes in your markup. Oh, and did we mention it's responsive? Runs on LESS, SCSS, or Stylus. Read up on Smashing Mag.