<input type="radio" name="isSponsor" class="activity-radio">
<input type="radio" name="isSponsor" class="activity-radio">

.activity-radio {
    width: 20px;
    height: 0px;
    background-color: #777;
    margin-right: 30px;
    border-radius: 50%;
    position: relative;
}
.activity-radio:before,.activity-radio:after {
    content: '';
    display: block;
    position: absolute;
    border-radius: 50%;
    transition: .3s ease;
}
.activity-radio:before {
    top: 0px;
    left: 0px;
    width: 18px;
    height: 18px;
    background-color: #fff;
    border: 1px solid #777;
}
.activity-radio:after {
    top: 6px;
    left: 6px;
    width: 8px;
    height: 8px;
    background-color: #fff; 
}
.activity-radio:checked:after {
    top: 3px;
    left: 3px;
    width: 12px;
    height: 12px;
    background-color:#FFBA3C; 
}
.activity-radio:checked:before {
    border-color:#FFBA3C; 
}
 

如圖：

原文 https://blog.csdn.net/promisecao/article/details/54029848