Metallic grey, like a semiconductor in a circuit board.
Selenium is a neutral grey.
It can be described as neutral, medium, colorless and almost grey.
Set in black, because black reads best on it.
Selenium is a chemical element; it has symbol Se and atomic number 34. It has various physical appearances, including a brick-red powder, a vitreous black solid, and a grey metallic-looking form. It seldom occurs in this elemental state or as pure ore compounds in Earth's crust. Selenium was discovered in 1817 by Jöns Jacob Berzelius, who noted the similarity of the new element to the previously discovered tellurium.
Read on WikipediaSelenium is an open source umbrella project for a range of tools and libraries aimed at supporting browser automation. It provides a playback tool for authoring functional tests across most modern web browsers, without the need to learn a test scripting language. It also provides a test domain-specific language (Selenese) to write tests in a number of popular programming languages, including JavaScript (Node.js), C#, Groovy, Java, Perl, PHP, Python, Ruby and Scala. Selenium runs on Windows, Linux, and macOS. It is open-source software released under the Apache License 2.0.
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