* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body {
    font-family: "Microsoft Yahei", system-ui, sans-serif;
    background-color: #fff;
    color: #333;
}
/* ======================头部导航====================== */
.header-wrap {
    background-color: #4078e8;
    color: #fff;
}
.header-container {
    max-width: 1280px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    padding:0 16px;
    height: 56px;
}
.header-logo-area {
    display: flex;
    align-items: center;
    gap:8px;
}
.header-logo-text {
    font-size:16px;
}
.header-nav {
    flex:1;
    margin-left:24px;
}
.header-nav ul {
    display:flex;
    list-style:none;
    gap:4px;
}
.header-nav a {
    color:#ffffff;
    text-decoration:none;
    font-size:14px;
    padding: 8px 12px;
    border-radius:4px;
}
.header-nav a:hover,.header-nav a.active {
    background-color:#3366cc;
}
.header-user {
    display:flex;
    align-items:center;
    gap:6px;
}
.user-avatar {
    width:28px;
    height:28px;
    border-radius:50%;
    background:#fff;
    display:flex;
    align-items:center;
    justify-content:center;
    color:#4078e8;
}
/* 移动端头部 */
@media(max-width:768px){
    .header-container{
        height:auto;
        flex-wrap:wrap;
        padding:12px 16px;
    }
    .header-nav{
        width:100%;
        margin:8px 0 0;
        overflow-x:auto;
    }
    .header-nav ul{
        flex-wrap:nowrap;
    }
}
/* =====================品牌切换栏【修复logo视觉大小不一致】===================== */
.brand-tab-wrap{
    max-width:1280px;
    margin:116px auto 0;
    padding:0 16px;
}
.brand-tabs{
    display:flex;
    flex-wrap: wrap;
    column-gap:14px;
    row-gap:8px;
    justify-content: flex-start;
    padding:8px 12px;
    background:#ffffff;
    border-radius:8px;
}
.brand-item{
    cursor:pointer;
    padding:8px 12px;
    border:2px solid transparent;
    border-radius:6px;
    flex: 0 0 calc(16.666% - 12px);
}
.brand-item.active{
    border-color:#f5f5f573;
    background-color:#fff;
}
/* logo容器固定 */
.logo-box{
    width:100%;
    height:60px;
    display:flex;
    align-items:center;
    justify-content:center;
}
.brand-item img{
    max-width:110px;
    max-height:46px;
    object-fit:contain;
    pointer-events:none;
}
/* 手机端：每行2个 */
@media (max-width:768px) {
    .brand-item {
        flex: 0 0 calc(50% - 8px);
    }
    .brand-item{
        padding:8px 10px;
    }
    .logo-box{
        height:52px;
    }
    .brand-tabs{
        row-gap:20px;
    }
    .brand-item img{
        max-width:90px;
        max-height:40px;
    }
}
/* =====================PDF iframe容器==================== */
.pdf-view-container{
    max-width:1280px;
    margin:16px auto 40px;
    padding:0 16px;
}
.pdf-reader-box{
    background:#e2e4e8;
    border-radius:8px;
    overflow:hidden;
}
/* PDF顶部工具栏模拟 */
.pdf-toolbar{
    background:#ffffff;
    padding:8px 12px;
    display:flex;
    gap:12px;
    align-items:center;
    border-bottom:1px solid #ddd;
}
.tool-icon{
    width:24px;
    height:24px;
    display:flex;
    align-items:center;
    justify-content:center;
    border-radius:4px;
}
/* iframe PDF区域 */
.pdf-iframe-wrap{
    width:100%;
    height:720px;
    position:relative;
}
#pdfIframe{
    width:100%;
    height:100%;
    border:none;
}
.tip-text{
    position:absolute;
    top:12px;
    left:12px;
    z-index:2;
    color:#666;
}
@media(max-width:768px){
    .pdf-iframe-wrap{
        height:520px;
    }
}
/* =================页脚=================== */
footer{
    background:#2c313a;
    color:#cccccc;
    padding:32px 16px;
}
.footer-inner{
    max-width:1280px;
    margin:0 auto;
    display:grid;
    grid-template-columns:repeat(3,1fr);
    gap:24px;
}
.footer-block h4{
    color:#fff;
    margin-bottom:12px;
    font-size:16px;
}
.footer-block a{
    color:#cccccc;
    text-decoration:none;
    display:block;
    margin:6px 0;
}
.footer-block a:hover{
    color:#fff;
}
.footer-copyright{
    max-width:1280px;
    margin:24px auto 0;
    padding-top:16px;
    border-top:1px solid #444952;
    font-size:13px;
}
@media(max-width:768px){
    .footer-inner{
        grid-template-columns:1fr;
    }
}