How to create a custom select menu?

I have been into many situations while converting designs to HTML where designs demanded a custom select menu. There is a simple solution to this by W3Schools. You can copy and modify what's needed without getting deep down to the basics and mechanism.

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DEMO

See the Pen Custom select menu by Puneet Sharma (@webdevpuneet) on CodePen.

Credits: https://www.w3schools.com/howto/howto_custom_select.asp