/* 字體 */
    @font-face {
        font-family: 'cwTeXYen';
        font-style: normal;
        font-weight: bold;
        src: url(https://fonts.gstatic.com/ea/cwtexyen/v3/cwTeXYen-zhonly.eot);
        src: url(https://fonts.gstatic.com/ea/cwtexyen/v3/cwTeXYen-zhonly.eot?#iefix) format('embedded-opentype'),
            url(https://fonts.gstatic.com/ea/cwtexyen/v3/cwTeXYen-zhonly.woff2) format('woff2'),
            url(https://fonts.gstatic.com/ea/cwtexyen/v3/cwTeXYen-zhonly.woff) format('woff'),
            url(https://fonts.gstatic.com/ea/cwtexyen/v3/cwTeXYen-zhonly.ttf) format('truetype');
    }

    * {
        transition: 0.5s;
    }

    body {
        font-family: 'cwTeXYen', sans-serif;
        font-weight: bold;
        margin: 0;
        background-image: url('./images/totoro.jpg');
        background-position: center;
        background-repeat: no-repeat;
        background-size: cover;
        background-attachment: fixed;
    }

    #area {
        width: 600px;
        height: 550px;
        background: rgba(0, 0, 0, 0.3);
        position: absolute;
        left: 50%;
        top: 50%;
        transform: translate(-50%, -50%);
        border-radius: 30px;
    }

    #game {
        width: 500px;
        margin: 50px auto 0;
    }

    .card {
        width: 100px;
        height: 120px;
        position: relative;
        float: left;
        margin: 10px;
        transition: 1s;
        /* 設定子元素在 3D 空間內 */
        transform-style: preserve-3d;
    }

    /* 卡牌正面 */
    .card-front {
        width: 100%;
        height: 100%;
        background-image: url('./images/totoro1.jpg');
        background-size: contain;
        background-repeat: no-repeat;
        background-position: center;
        position: absolute;
        /* 設定隱藏背面 */
        backface-visibility: hidden;
    }

    /* 卡牌背面 */
    .card-back {
        width: 100%;
        height: 100%;
        background-image: url('./images/totoro_back.jpg');
        background-size: contain;
        background-repeat: no-repeat;
        background-position: center;
        position: absolute;
        transform: rotateY(180deg);
        /* 設定隱藏背面 */
        backface-visibility: hidden;
    }

    .card-close {
        transform: rotateY(180deg);
    }

    p:not(#text-theme) {
        width: 20%;
        font-size: 20px;
        line-height: 50px;
        margin: 0 100px 0 0;
        text-align: right;
        font-size: 1.5rem;
        float: right;
        color: #fff;
    }

    p:first-child:not(#text-theme) {
        float: left;
        text-align: left;
        margin: 0 0 0 100px;
    }

    #btnStart,
    #index,
    #lookMe {
        padding: 0.5rem 1.5rem;
        border-radius: 10px;
        font-size: 1.5rem;
        background: #D9AC1D88;
        color: #fff;
        position: absolute;
        transform: translate(-50%, -50%);
    }

    /* 開始鍵 */
    #btnStart,
    #index {
        left: 50%;
        top: 92%;
    }

    #lookMe {
        padding: 0.5rem 1rem;
        font-size: 0.5rem;
        background: #00234388;
        left: 50%;
        top: 83%;
        z-index: 1;
    }

    #info {
        width: 40%;
        padding: 1rem;
        background: rgba(0, 0, 0, 0.8);
        color: #fff;
        text-align: center;
        position: absolute;
        left: 50%;
        top: 50%;
        z-index: -1;
        transform: translate(-50%, -50%);
        opacity: 0;
    }

    /* 實時狀況 */
    #instant {
        color: #fff;
        text-align: center;
        font-size: 1.5rem;
        position: absolute;
        transform: translate(-50%, -50%);
        left: 50%;
        top: 35%;
        line-height: 2;
    }

    #btnClose {
        margin: 10px auto 0;
        width: 20%;
        background: #aaa;
        color: #000;
    }

    #btnStart:hover,
    #index:hover,
    #btnClose:hover {
        background: #e4cd83;
        color: #333;
        cursor: pointer;
    }

    #lookMe:hover {
        background: #4994A9;
        cursor: pointer;
    }

    .radio,
    #index {
        display: none;
    }

    /* 卡牌主題區 */
    #bg {
        width: 100%;
        position: absolute;
        text-align: center;
        margin: 0 auto 0;
        font-size: 1.5rem;
        line-height: 2rem;
    }

    label:hover {
        cursor: pointer;
    }

    #bg img {
        width: 230px;
        height: 80px;
        margin: 10px;
    }

    #bg img:hover:not(#title) {
        box-shadow: 0 0 10px #eee;
    }