/* 自定义模态框样式 */
.modal {
    visibility: hidden; /* 初始状态隐藏 */
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    opacity: 0; /* 初始透明度 */
    transition: visibility 0s, opacity 0.2s linear; /* 动画效果 */
}
.modal.show {
    visibility: visible; /* 显示状态 */
    opacity: 1; /* 透明度过渡到显示 */
}
.modal-content {
    margin: auto;
    display: block;
    width: 80%;
    max-width: 700px;
    animation-name: zoom;
    animation-duration: 0.6s;
}
@keyframes zoom {
    from { transform: scale(0) }
    to { transform: scale(1) }
}
.close {
    position: absolute;
    top: 15px;
    right: 35px;
    color: #f1f1f1;
    font-size: 40px;
    font-weight: bold;
    transition: 0.1s;
}
.close:hover,
.close:focus {
    color: #bbb;
    text-decoration: none;
    cursor: pointer;
}