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Regexp for HTML colors

Create a regexp to search HTML-colors written as #ABCDEF: first # and then 6 hexadimal characters.

An example of use:

let reg = /...your regexp.../

let str = "color:#121212; background-color:#AA00ef bad-colors:f#fddee #fd2 #12345678";

alert( str.match(reg) )  // #121212,#AA00ef

P.S. In this task we do not need other color formats like #123 or rgb(1,2,3) etc.

We need to look for # followed by 6 hexadimal characters.

A hexadimal character can be described as [0-9a-fA-F]. Or if we use the i flag, then just [0-9a-f].

Then we can look for 6 of them using the quantifier {6}.

As a result, we have the regexp: /#[a-f0-9]{6}/gi.

let reg = /#[a-f0-9]{6}/gi;

let str = "color:#121212; background-color:#AA00ef bad-colors:f#fddee #fd2"

alert( str.match(reg) );  // #121212,#AA00ef

The problem is that it finds the color in longer sequences:

alert( "#12345678".match( /#[a-f0-9]{6}/gi ) ) // #12345678

To fix that, we can add \b to the end:

// color
alert( "#123456".match( /#[a-f0-9]{6}\b/gi ) ); // #123456

// not a color
alert( "#12345678".match( /#[a-f0-9]{6}\b/gi ) ); // null