*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: "Microsoft YaHei", "PingFang SC", sans-serif;
    background: #fff;
}

a {
    color: inherit;
    text-decoration: none;
}

/* ========== Banner ========== */
.banner {
    position: relative;
    width: 100%;
    height: 800px;
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
}

/* ========== Title ========== */
.title-section {
    text-align: center;
    padding-top: 50px;
}

.title-section h1 {
    font-size: 36px;
    font-weight: 600;
    color: #fff;
    letter-spacing: 2px;
}

.title-section p {
    font-size: 16px;
    color: #e5e5e5;
    margin-top: 12px;
    letter-spacing: 4px;
}

/* ========== Product Nav (独立一行) ========== */
.product-nav {
    display: flex;
    justify-content: center;
    gap: 8px;
    padding: 30px 20px 20px;
    flex-wrap: wrap;
}

.product-nav-item {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 6px;
    padding: 10px 16px;
    cursor: pointer;
    border-radius: 8px;
    transition: all 0.3s ease;
    position: relative;
}

.product-nav-item:hover {
    background: rgba(255, 255, 255, 0.15);
}

.product-nav-item.active {
    background: rgba(255, 255, 255, 0.2);
}

.product-nav-item .icon-box {
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.product-nav-item .icon-box i,
.product-nav-item .icon-box svg {
    width: 20px;
    height: 20px;
    color: #fff;
    stroke: #fff;
}

.product-nav-item .icon-box svg * {
    stroke: #fff;
}

.product-nav-item span {
    font-size: 14px;
    color: #ddd;
    white-space: nowrap;
}

.product-nav-item.active span {
    color: #fff;
    font-weight: 500;
}

.product-nav-item .underline {
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 2px;
    background: transparent;
    transition: width 0.3s ease;
}

.product-nav-item.active .underline {
    background: #ffd700;
    width: 80%;
}

/* ========== Main Content (轮播+二维码) ========== */
.main-content {
    display: flex;
    justify-content: center;
    gap: 40px;
    padding: 20px 40px 0;
}

/* Carousel */
.carousel-section {
    width: 610px;
    height: 400px;
    overflow: hidden;
}

.carousel-track {
    display: flex;
    height: 100%;
    transition: transform 0.5s ease;
}

.carousel-slide {
    flex: 0 0 610px;
    width: 610px;
    height: 100%;
}

.carousel-slide a {
    display: block;
    width: 100%;
    height: 100%;
}

.carousel-slide img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

/* Sidebar QR */
.sidebar-qr {
    width: 220px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 15px;
    padding-top: 80px;
}

.qr-box {
    width: 140px;
    height: 140px;
    background: #fff;
    border-radius: 8px;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.qr-box img {
    width: 100%;
    height: 100%;
}

.sidebar-qr .phone {
    font-size: 18px;
    color: #333;
    font-weight: 500;
}

.sidebar-qr .icp {
    font-size: 12px;
    color: #666;
    text-align: center;
    line-height: 1.8;
}

.sidebar-qr .icp a {
    color: #666;
}

.sidebar-qr .icp a:hover {
    color: #c41e2a;
}

.download-btn {
    display: block;
    width: 100%;
    padding: 12px 20px;
    background: #c41e2a;
    color: #fff;
    border: none;
    border-radius: 25px;
    font-size: 16px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
}

.download-btn:hover {
    background: #a01822;
}

/* Footer */
.footer {
    position: absolute;
    bottom: 20px;
    left: 0;
    width: 100%;
    text-align: center;
    font-size: 12px;
    color: rgba(255,255,255,0.6);
}

.footer a {
    color: rgba(255,255,255,0.7);
    margin: 0 8px;
}

.footer a:hover {
    color: #fff;
}

/* Responsive */
@media (max-width: 900px) {
    .main-content {
        flex-direction: column;
        align-items: center;
    }

    .sidebar-qr {
        padding-top: 20px;
        flex-direction: row;
        flex-wrap: wrap;
        justify-content: center;
        width: 100%;
    }
}

@media (max-width: 650px) {
    .banner {
        height: auto;
        min-height: 600px;
    }

    .title-section h1 {
        font-size: 24px;
    }

    .product-nav {
        gap: 4px;
    }

    .product-nav-item {
        padding: 8px 10px;
    }

    .product-nav-item span {
        font-size: 12px;
    }

    .carousel-section {
        width: 100%;
        height: 250px;
    }

    .carousel-slide {
        flex: 0 0 100%;
        width: 100%;
    }
}