/* 去掉各种不必要 */
 * {
     margin: 0;
     padding: 0;
     /* 各种列表样式为空 */
     text-decoration: none;
     list-style: none;
 }

 .nav {
     position: fixed;
     top: 0;
     left: 0;
     z-index: 1001;
     height: 80px;
     width: 100%;
     transition: background-color 0.3s ease;
     /* 添加过渡效果 */

 }
 .nav:hover {
     background: white;
 }

 .nav.scrolled {
     background: white;
 }

 .navlist {
     position: relative;
     margin-left: 320px;
     font-weight: 400;
     color: #1f1f1f;
 }

 .btli {
     float: left;
     width: 100px;
     line-height: 80px;
     text-align: center;
     position: relative;
      margin: 0 25px;

 }

 .navlist a {
     color: white;
     /* 以块的形式来表示 */
     display: block;
     text-align: center;
     font-size: 18px;
 }

 /* 页面滚动时文字变黑色 */
 .nav.scrolled .navlist a {
     color: black;
 }

 .nav:hover .navlist a {
     color: black;
 }

 .navlist a:hover {
     color: rgb(37, 50, 235) !important;
 }

 .droplist {
    background: #fff;
    display: none;
    overflow: hidden;
    position: absolute;
    top: 100%; /* 放在父元素下方 */
    left: 50%; /* 相对于父元素左边缘50%位置 */
    transform: translateX(-50%); /* 向左移动自身宽度的50% */
    width: max-content; /* 宽度根据内容自适应 */
    min-width: 180px;
    z-index: 1000;
    text-align: center;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    border-radius: 4px;
    padding: 10px 0; /* 添加内边距 */
 }

 
/* 确保下拉项也是居中的 */
.droplist li {
    text-align: center;
    margin: 0;
}
 /* 鼠标悬停导航项时下拉 */
 .btli:hover .droplist {
     display: block;
 }

 .droplist li a {
     color: rgb(41, 40, 40);
     white-space: nowrap;
     display: block;
     padding:10px 20px;
     text-align: center;
     
 }

 .logo {
     width: 160px;
     height: 80px;
     position: absolute;
     margin-left: 150px;
     
    

 }

 .logo img {
     position: absolute;
   

     /* width: 160px; */
     height: 100%;
     
 }