⊟ SQUARED MINUS UTF-8 character with hex code 229F

Using HEX code of SQUARED MINUS in HTML file

<span> &#x229F; </span>

Using Decimal code of SQUARED MINUS in HTML file

<span> &#8863; </span>

Using HEX code of SQUARED MINUS in CSS file for content

span { 
    content: '\229f';
}