≔ COLON EQUALS UTF-8 character with hex code 2254

Using HEX code of COLON EQUALS in HTML file

<span> &#x2254; </span>

Using Decimal code of COLON EQUALS in HTML file

<span> &#8788; </span>

Using HEX code of COLON EQUALS in CSS file for content

span { 
    content: '\2254';
}