the CSS:
label {
display: inline-block;
cursor: pointer;
position: relative;
padding-left: 25px;
margin-right: 15px;
font-size: 13px;
}
input[type=radio] {
display: none;
}
label:before {
content: "";
display: inline-block;
width: 16px;
height: 16px;
margin-right: 10px;
position: absolute;
left: 0;
bottombottom: 1px;
background-color: #aaa;
box-shadow: inset 0px 2px 3px 0px rgba(0, 0, 0, .3), 0px 1px 0px 0px rgba(255, 255, 255, .8);
}
input[type=radio]:checked + label:before {
content: "\2022";
color: #f3f3f3;
font-size: 30px;
text-align: center;
line-height: 18px;
}
.radio label:before {
border-radius: 8px;
}
the HTML
<div class="radio">
<input id="male" type="radio" name="gender" value="male">
<label for="male">Male</label>
<input id="female" type="radio" name="gender" value="female">
<label for="female">Female</label>
</div>