.answer {
        position: relative;
        display: inline-block;
        margin-right: 10px;
        width: 40px;
        height: 40px;
        line-height: 50px;
        text-align: center;
        font-size: 50px;
        border: 2px solid #ccc;
        cursor: pointer;
    }
    .answer input[type="checkbox"] {
        display: none; /* Òþ²ØĬÈϵĸ´Ñ¡¿ò */
    }
    .answer span.feedback {
        display: none;
        position: absolute;
        top: -10px;
        left: -8px;
        width: 100%;
        height: 100%;
        font-size: 1.5em;
    }
    .answer .correct {
        color: green;
    }
    .answer .incorrect {
        color: red;
    }
    .label {
        font-size: 2.5em;
        vertical-align: top;
        margin-left: 5px;
    }