input radio checked css code example
Example 1: checked radio button css
//html
<input id="rad1" type="radio" name="rad"/><label for="rad1">Radio 1</label>
<input id="rad2" type="radio" name="rad"/><label for="rad2">Radio 2</label>\
//css
input[type="radio"]:checked+label { font-weight: bold; }
Example 2: html radio button checked
<input type="radio" id="huey" name="drone" value="huey"
checked>
Example 3: html radio only one checked
<input type="radio" name="options" id="1"/>
<input type="radio" name="options" id="2"/>