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

:root {
    --theme-color: #1e50ae;
    --text-color: #212121;
    --dark-bg: rgba(38, 37, 37, 1);
    --gray-bg: rgba(53, 53, 53, 1);
    --light-gray-bg: rgba(249, 249, 249, 1);
    --btn-blue: rgba(31, 135, 232, 1);
}

body {
    font-family: "Microsoft YaHei", "微软雅黑", "SimHei", sans-serif;
    color: var(--text-color);
    line-height: 1.5;
    background-color: #fff;
    font-size: 16px;
}

a { text-decoration: none; color: inherit; }
ul { list-style: none; }
img { max-width: 100%; display: block; }

/* Header */
.header {
    background-color: #fff;
    border-bottom: 1px solid rgba(232, 232, 232, 1);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding-top: 1.56vw;
}

.header-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 61px;
}

.logo-text {
    font-size: 20px;
    font-weight: bold;
    color: var(--text-color);
}

.nav-list {
    display: flex;
    gap: 30px;
}

.nav-item a {
    font-size: 16px;
    color: var(--text-color);
    transition: color 0.3s;
    padding: 10px 0;
    display: inline-block;
}

.nav-item a:hover,
.nav-item.active a {
    color: var(--theme-color);
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.mobile-menu-btn span {
    width: 25px;
    height: 3px;
    background-color: var(--text-color);
    transition: all 0.3s;
}

/* Banner - aspect ratio 23.72% */
.banner {
    width: 100%;
    overflow: hidden;
    position: relative;
}

.banner::before {
    content: "";
    display: block;
    padding-bottom: 23.7179%;
}

.banner-img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: 50% 50%;
}

/* Cases section (row240) */
.cases-section {
    padding: 0;
}

.cases-header {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
    display: flex;
    align-items: center;
    position: relative;
    min-height: 60px;
}

.cases-title {
    font-size: 30px;
    color: rgb(53, 53, 53);
    font-weight: normal;
    margin-top: 3.18vw;
    margin-left: 16.72%;
    margin-right: 40.75%;
    white-space: nowrap;
}

.cases-btn {
    margin-top: 3.18vw;
    margin-left: 0;
    margin-right: 19.01%;
    background-color: var(--theme-color);
    color: #fff;
    border: none;
    border-radius: 0;
    padding: 0 20px;
    font-size: 14px;
    cursor: pointer;
    height: 43px;
    line-height: 43px;
    display: inline-block;
    transition: opacity 0.3s;
    font-family: inherit;
}

.cases-btn:hover { opacity: 0.85; }

/* Products section (row234) */
.products-section {
    background-color: #fff;
    padding: 0 0 0.2vw 0;
}

.products-inner {
    background-color: var(--gray-bg);
    max-width: 1200px;
    margin: 0 auto;
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    padding: 0 0.61% 0 5.47%;
}

.product-item {
    padding: 10px 8px;
    text-align: center;
    transition: transform 0.3s;
    text-decoration: none;
    color: inherit;
    display: block;
}

.product-item:hover { transform: translateY(-5px); }

.product-item img {
    width: 100%;
    aspect-ratio: 1;
    object-fit: contain;
    background-color: #fff;
}

.product-name {
    margin-top: 8px;
    font-size: 14px;
    color: #fff;
}

/* About section (row235) */
.about-section {
    border-top: 1px solid rgba(169, 169, 169, 1);
    background-color: #fff;
    padding: 2.28vw 0 0 0;
}

.about-wrapper {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
    display: flex;
}

.about-left {
    flex: 0 0 40%;
    margin-top: 1.3vw;
    margin-left: 1.96%;
}

.about-title {
    font-size: 36px;
    color: rgb(0, 0, 0);
    font-weight: normal;
    line-height: 50px;
    margin-bottom: 15px;
}

.about-btn {
    display: inline-block;
    background-color: #fff;
    color: var(--btn-blue);
    border: 1px solid var(--btn-blue);
    border-radius: 20px;
    padding: 0 25px;
    font-size: 14px;
    cursor: pointer;
    height: 50px;
    line-height: 50px;
    transition: all 0.3s;
    font-family: inherit;
}

.about-btn:hover {
    background-color: var(--btn-blue);
    color: #fff;
}

.about-right {
    flex: 1;
    padding: 0 14.1% 2.6vw 3.03%;
    margin-top: 1.3vw;
}

.about-text {
    font-size: 18px;
    line-height: 30px;
    color: rgb(0, 0, 0);
    font-family: "SimSun", "宋体", serif;
}

/* News section (row287 + row238) */
.news-heading {
    text-align: center;
    padding: 20px 0;
}

.news-heading h2 {
    font-size: 36px;
    color: rgb(0, 0, 0);
    font-weight: normal;
}

.news-content {
    padding: 0 7.84%;
}

.news-list {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    gap: 0;
}

.news-item {
    flex: 1;
    padding: 15px;
}

.news-item:first-child { margin-right: 4.6%; }
.news-item:last-child { margin-left: 1.98%; }

.news-title {
    font-size: 16px;
    font-weight: normal;
    color: var(--text-color);
    margin-bottom: 8px;
    line-height: 1.4;
}

.news-date {
    font-size: 13px;
    color: #999;
    display: block;
    margin-bottom: 8px;
}

.news-summary {
    font-size: 14px;
    color: #666;
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 4;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* News images (row236) */
.news-images {
    background-color: #fff;
    padding: 0 0 5.2vw 0;
}

.news-images-grid {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 8.62%;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0;
}

.news-img-item img {
    width: 100%;
    height: auto;
    display: block;
}

/* Contact section (row269) */
.contact-section {
    overflow: hidden;
}

.contact-wrapper {
    display: flex;
    max-width: 1200px;
    margin: 0 auto;
}

.contact-info {
    flex: 0 0 40%;
    background-color: var(--light-gray-bg);
    padding: 40px 30px;
}

.contact-title {
    font-size: 24px;
    color: var(--text-color);
    margin-bottom: 20px;
    font-weight: normal;
}

.contact-detail {
    font-size: 15px;
    color: #555;
    line-height: 2;
}

.contact-label {
    color: #999;
}

.qrcode-area {
    margin-top: 20px;
    text-align: center;
}

.qrcode-img {
    width: 120px;
    height: 120px;
    margin: 0 auto;
    border: 1px solid #ddd;
    padding: 5px;
    background-color: #fff;
}

.qrcode-text {
    font-size: 13px;
    color: #777;
    margin-top: 8px;
}

.contact-form-area {
    flex: 1;
    background-color: var(--dark-bg);
    padding: 30px 3.18% 30px 3.18%;
}

.contact-form {
    max-width: 100%;
}

.form-row {
    display: flex;
    gap: 0;
    margin-bottom: 12px;
}

.form-input {
    flex: 1;
    padding: 10px 12px;
    border: 1px solid #555;
    background-color: rgba(255, 255, 255, 0.1);
    color: #fff;
    font-size: 14px;
    font-family: inherit;
    margin-right: 4px;
}

.form-input:last-child { margin-right: 0; }

.form-input::placeholder { color: #aaa; }

.form-textarea {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid #555;
    background-color: rgba(255, 255, 255, 0.1);
    color: #fff;
    font-size: 14px;
    font-family: inherit;
    resize: vertical;
    min-height: 80px;
    margin-bottom: 12px;
}

.form-textarea::placeholder { color: #aaa; }

.btn-submit {
    background-color: var(--theme-color);
    color: #fff;
    border: none;
    padding: 10px 30px;
    font-size: 14px;
    cursor: pointer;
    font-family: inherit;
    transition: opacity 0.3s;
}

.btn-submit:hover { opacity: 0.85; }

/* Footer (row4) */
.footer {
    background-color: var(--dark-bg);
    padding: 10px 0;
}

.footer-inner {
    text-align: center;
}

.copyright {
    font-size: 14px;
    color: #999;
}

.copyright .copy-symbol { color: #474747; }

/* Responsive */
@media screen and (max-width: 768px) {
    .header { padding-top: 0; }
    .header-inner { height: 50px; }
    .logo-text { font-size: 16px; }

    .mobile-menu-btn { display: flex; }

    .nav {
        position: fixed;
        top: 50px;
        left: 0;
        width: 100%;
        background-color: #fff;
        border-bottom: 1px solid #eee;
        transform: translateY(-100%);
        transition: transform 0.3s;
        z-index: 999;
    }

    .nav.active { transform: translateY(0); }

    .nav-list { flex-direction: column; gap: 0; }
    .nav-item { border-bottom: 1px solid #f0f0f0; }
    .nav-item a { padding: 12px 20px; display: block; }

    .banner::before { padding-bottom: 26.04%; }

    .cases-header { padding: 0 15px; }
    .cases-title { margin-left: 3.73%; margin-right: 6.91%; margin-top: 1.87vw; font-size: 24px; }
    .cases-btn { margin-right: 0; margin-top: 0.8vw; }

    .products-grid { grid-template-columns: repeat(2, 1fr); padding: 0 15px; }
    .product-item img { aspect-ratio: 1; }

    .about-wrapper { flex-direction: column; }
    .about-left { margin-left: 3.73%; margin-right: 3.73%; }
    .about-right { padding: 0 3.73%; }

    .news-content { padding: 0 3.73%; }
    .news-list { flex-direction: column; }
    .news-item:first-child { margin-right: 0; }
    .news-item:last-child { margin-left: 0; }

    .news-images-grid { grid-template-columns: 1fr; padding: 0 15px; }

    .contact-wrapper { flex-direction: column; }
    .contact-info { flex: 1; }
    .contact-form-area { padding: 20px 3.73%; }
    .form-row { flex-direction: column; }
    .form-input { margin-right: 0; margin-bottom: 10px; }
}

@media screen and (max-width: 480px) {
    .products-grid { grid-template-columns: 1fr; }
}