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The color names that can be used in standard HTML are given in the standards document here. Using the hexadecimal RGB-style colors (such as #008000) you can choose any color you like from about sixteen million, not just the 140 colors that have names in standard HTML.
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Today's featured picture
The Battle of Inab, also called the Battle of Ard al-Hâtim or Fons Muratus, was fought on 29 June 1149 during the Second Crusade. The Zengid army of Nur al-Din Zengi destroyed the combined army of Raymond of Poitiers and the Assassins of Ali ibn-Wafa. The Principality of Antioch was subsequently pillaged and reduced in size as its eastern border was pushed west, and both Raymond and his ally ibn-Wafa were killed. This illustration by Jean Colombe was taken from the 14th-century manuscript Passages d'outremer and depicts the Battle of Inab in the main image above, with the recovery of Raymond's body depicted below. It is part of a volume of 66 such full-page miniatures.