.modal {
            display: none; /* 默认隐藏 */
            position: fixed;
            z-index: 1;
            left: 0;
            top: 0;
            width: 100%;
            height: 100%;
            overflow: auto;
            background-color: rgba(0,0,0,0.4);
        }

        .modal-content {
            background-color: #fefefe;
            margin: 15% auto;
            padding: 20px;
            border: 1px solid #888;
            width: 80%;
        }

        .close {
            color: #aaa;
            float: right;
            font-size: 28px;
            font-weight: bold;
        }

        .close:hover,
        .close:focus {
            color: black;
            text-decoration: none;
            cursor: pointer;
        }