.menu {
    /*文字*/
    font-size: 25px;
    /*透明度*/
    background-color: rgba(0,0,0,.4);
    /*邊框 角弧度*/
    border-radius: 10px;
    border: 10px solid #fff;
    /*陰影*/
    box-shadow: 0 0 10px #000;
    /*寬度*/
    width: 100%;
    /*置中*/
    margin-left: auto;
    margin-right: auto;
    /*下方預留空間*/
    margin-bottom: 20px;
    /*flex*/
    display: flex;
    flex-direction: column;
    /*文字置中*/
    text-align: center;
    /*文字顏色*/
    color: white;
}

    .menu a {
        display: block;
        padding: 10px;
        color: black;
        text-decoration: none;
        position: relative;
        font-weight:300;
        font-size:1.5rem;
        cursor: pointer;
    }

        .menu a:hover {
            background-color: #808080;
        }
    /*繪製分割線*/
    .menu p ~ a::before {
        content: "";
        position: absolute;
        border-top: 1px solid black;
        left: 10px;
        right: 10px;
        top: 0;
    }

.item {
    position: relative;
    left: -150%;
    display: none;
}