html, body {
    margin: 0;
    height: 100%;
    font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
    background-color: #000;
    color: #ccc;
}

header, footer {
    width: 100%;
    background: #000;
    color: #ccc;
}

.content {
  flex: 1;
}

.container {
    max-width: 1800px;
    margin: 0 auto;
    padding: 0px;
}

/* 顶部导航 */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-left {
    display: flex;
    align-items: center;
    cursor: pointer;
}

.nav-left img {
    height: 40px;
    margin-right: 10px;
}

.nav-right a {
    margin-left: 20px;
    text-decoration: none;
    color: #999;
    font-weight: bold;
}

.nav-right a:hover {
    color: #0078ff;
}

/* 底部信息 */
footer {
    border-top: 1px solid #666; 
    text-align: center;
    font-size: 14px;
    padding: 20px 10px;
    background: #000;
}

footer a {
    color: #000;
    text-decoration: none;
}

.footer-links {
    text-align: center;
    margin-top: 40px;
    color: #999;
}

.footer-links h2 {
    margin-bottom: 10px;
}

.footer-links a {
    display: inline-block;
    margin: 8px 12px;
    color: #999;
    text-decoration: none;
}

.footer-links a:hover {
    text-decoration: underline;
}

/* 宣传图 */
.promo {
  display: flex;
  flex-direction: column;  
  align-items: center;     
  gap: 0px;                
  box-sizing: border-box;
}

.promo img {
  width: 100%;             
  height: auto;            
}

/* 入口导航 */
.nav-sections {
  display: flex;
  justify-content: center; 
  align-items: flex-start; 
  gap: 80px;               
  margin: 60px auto;
  flex-wrap: wrap;         
}

.section {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.section h3 {
  font-size: 20px;
  color: #999;
  margin-bottom: 20px;
  font-weight: bold;
}

.section a {
  color: #999;
  text-decoration: none;
  margin: 8px 0;
  font-size: 16px;
  transition: color 0.2s ease;
}

.section a:hover {
  text-decoration: underline;
}

/* 小屏优化 */
@media (max-width: 768px) {
  .nav-sections {
    gap: 40px;
  }
  .section h3 {
    font-size: 18px;
  }
}

/* 下载页 */
.download-tabs {
    display: flex;
    justify-content: center;
    margin: 20px 0;
    gap: 15px;
}

.tab {
    padding: 10px 20px;
    border: 1px solid #ccc;
    border-radius: 20px;
    cursor: pointer;
}

.tab.active {
    background-color: #0078ff;
    color: white;
    border-color: #0078ff;
}

.download-content {
    text-align: center;
}

.download-content img {
    max-width: 500px;
    width: 100%;
    border-radius: 10px;
}

.download-content button {
    margin-top: 15px;
    padding: 10px 25px;
    background-color: #0078ff;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
}
.download-content button:hover {
    background-color: #005fd1;
}

.pagehead {
    font-family: Arial, Helvetica, sans-serif;
    font-size: 18px;
    font-weight: bold;
    color: #990000;
}
.pageLinkhead {
    font-family: Verdana, Arial, Helvetica, sans-serif;
    font-size: 12px;
    font-weight: bold;
    color: #333333;
}
.pageLink {
    font-family: Verdana, Arial, Helvetica, sans-serif;
    font-size: 12px;
    font-weight: bold;
    color: #996666;
    text-decoration: none;
}
.pageLink:hover {
    text-decoration: underline;
}

.fb {
  font-weight: bold;   /* 加粗 */
  color: #000;         /* 黑色文字 */
}