Tincta Pro is an elegant and powerful one-window text editor that is intuitive to use but has all the functionality that you need for professional web design and programming.
It also provides script support (so you can run any Unix compatible scripts like Python, Shell or Perl), snippet manager (organize your snippets in groups and access them from the distinct snippets menu or by assigning each snippet a shortcut) and syntax coloring (comes with syntax color profiles for over 60 languages and very fast and reliable coloring algorithms).