There can never be enough legible, intentionally designed syntax themes for text editors. I designed newbound light (as well as its dark and warm alternatives) as a theme for Atom, based on the hues and shades from this website. Optimized for writing Markdown and for front-end development, it should also work with other syntaxes. The light theme is intended for general use where high but not harsh contrast (maximum ratio around 11:1) is desired. The dark and warm themes are better suited for late night work, and are intentionally slightly lower contrast (typically between 4.5:1 and 10:1).
Working with Atom as my primary text editor, I spend a lot of time looking at syntax-highlighted code. I carefully designed color palettes while creating my own website. I tweaked and refined those palettes for a pleasing, legible set of syntax theme colors. Leaning heavily on the existing syntax support and syntax themes built into Atom, I made adjustments to work especially well with Markdown, HTML, and CSS which I use for every project. I tested the themes thoroughly, lived with them for a while, and then published open source versions. I now use these syntax themes every day.