* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Microsoft YaHei', sans-serif;
}

:root {
    --primary: #165DFF;
    --dark: #0D1126;
    --light: #E8F3FF;
    --gray: #6E7681;
}

body {
    background: #fff;
    color: #333;
}

/* 导航栏 */
.nav {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(13, 17, 38, 0.85);
    padding: 15px 5%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 999;
    backdrop-filter: blur(10px);
}

.logo {
    color: #fff;
    font-size: 24px;
    font-weight: bold;
}

.nav-menu a {
    color: #fff;
    text-decoration: none;
    margin-left: 30px;
    font-size: 16px;
    transition: 0.3s;
}

.nav-menu a:hover, .nav-menu a.active {
    color: var(--primary);
}

/* 轮播 Banner */
.banner-slider {
    position: relative;
    width: 100%;
    height: 100vh;
    overflow: hidden;
}

.banner-slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 1.2s ease;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    color: #fff;
    padding: 0 20px;
}

.banner-slide.active {
    opacity: 1;
    z-index: 2;
}

.banner-slide:nth-child(1) {
    background: linear-gradient(rgba(13,17,38,0.35), rgba(13,17,38,0.55)), url('imges/b1.jpg') center/cover;
}
.banner-slide:nth-child(2) {
    background: linear-gradient(rgba(13,17,38,0.35), rgba(13,17,38,0.55)), url('imges/b2.jpg') center/cover;
}
.banner-slide:nth-child(3) {
    background: linear-gradient(rgba(13,17,38,0.35), rgba(13,17,38,0.55)), url('imges/b3.jpg') center/cover;
}

.banner-slide h1 {
    font-size: 52px;
    margin-bottom: 20px;
    background: linear-gradient(90deg, #fff, var(--primary));
    -webkit-background-clip: text;
    color: transparent;
}

.banner-slide p {
    font-size: 20px;
    color: var(--light);
    margin-bottom: 40px;
    max-width: 800px;
}

.dots {
    position: absolute;
    bottom: 60px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 12px;
    z-index: 10;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(255,255,255,0.5);
    cursor: pointer;
    transition: 0.3s;
}

.dot.active {
    background: var(--primary);
    width: 30px;
    border-radius: 10px;
}

.btn {
    padding: 14px 40px;
    background: var(--primary);
    color: #fff;
    border: none;
    border-radius: 50px;
    font-size: 16px;
    cursor: pointer;
    transition: 0.3s;
    text-decoration: none;
    margin: 0 10px;
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(22, 93, 255, 0.3);
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--primary);
}

/* 通用标题 */
.section-title {
    font-size: 36px;
    color: var(--dark);
    text-align: center;
    margin-bottom: 50px;
}

/* 核心产品 */
.product {
    padding: 90px 5%;
}
.product-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 30px;
    justify-content: center;
}
.product-item {
    width: 380px;
    background: #fff;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 5px 20px rgba(0,0,0,0.06);
    transition: 0.3s;
}
.product a {
    color: #fff;
    text-decoration: none;
    margin-left: 20px;
    font-size: 16px;
    transition: 0.3s;
}

.product-item:hover {
    transform: translateY(-6px);
    border: 1px solid #165DFF;
}
.product-img {
    padding-top: 20px;
    height: 270px;
    object-fit: cover;
    ;
}
.product-info {
    padding: 25px;
}
.product-info h3 {
    font-size: 20px;
    margin-bottom: 10px;
    color: var(--dark);
}
.product-info p {
    color: #666;
    line-height: 1.7;
    font-size: 15px;
}

/* 公司介绍 */
.about {
    padding: 90px 5%;
    background: #F7F9FC;
}
.about-row {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 50px;
}
.about-left {
    flex: 1;
    min-width: 300px;
}
.about-right {
    flex: 1;
    min-width: 300px;
}
.about-img {
    width: 100%;
    border-radius: 16px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}
.about-right h2 {
    font-size: 32px;
    margin-bottom: 20px;
    color: var(--dark);
}
.about-right p {
    font-size: 16px;
    line-height: 1.9;
    color: #555;
    margin-bottom: 15px;
}

/* 核心优势 */
.advantage {
    padding: 90px 5%;
    text-align: center;
}
.adv-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 30px;
}
.adv-card {
    width: 260px;
    padding: 40px 20px;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    transition: 0.3s;
}
.adv-card:hover {
    border: 1px solid var(--primary);
    transform: translateY(-8px);
}
.adv-icon {
    width: 50px;
    height: 50px;
    margin: 0 auto 15px;
    stroke: var(--primary);
    stroke-width: 1.5;
    fill: none;
}
.adv-card h3 {
    font-size: 20px;
    margin-bottom: 10px;
}
.adv-card p {
    color: #666;
}

/* 案例跑马灯 */
.case {
    padding: 70px 5%;
    background: var(--dark);
    color: #fff;
    overflow: hidden;
}
.case .section-title {
    color: #fff;
}
.marquee-box {
    width: 100%;
    overflow: hidden;
    padding: 20px 0;
}
.marquee {
    display: flex;
    width: max-content;
    animation: marquee 25s linear infinite;
}
.case-item {
    width: 280px;
    margin: 0 15px;
    background: #1a2238;
    border-radius: 12px;
    padding: 20px;
}
.case-img {
    width: 100%;
    height: 160px;
    border-radius: 8px;
    object-fit: cover;
    margin-bottom: 15px;
}
.case-item h3 {
    font-size: 18px;
    margin-bottom: 8px;
}
.case-item p {
    color: #ccc;
    font-size: 14px;
}
@keyframes marquee {
    0% { transform: translateX(0); }
    100% { transform: translateX(-50%); }
}

/* 联系我们 */
.contact {
    padding: 80px 5%;
    text-align: center;
    background: #F7F9FC;
}
.contact-info {
    max-width: 700px;
    margin: 0 auto;
    font-size: 18px;
    line-height: 2;
    color: #333;
}

/* 内页头部 */
.page-header {
    height: 360px;
    background: linear-gradient(rgba(13,17,38,0.4), rgba(13,17,38,0.6)), url('imges/about_bj.png') center/cover;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 42px;
    font-weight: 500;
    margin-top: 70px;
}

/* 产品内页 */
.product-page {
    padding: 100px 5%;
    max-width: 1200px;
    margin: 0 auto;
}
.product-page-item {
    background: #fff;
    border-radius: 16px;
    padding: 36px;
    margin-bottom: 30px;
    box-shadow: 0 6px 20px rgba(0,0,0,0.06);
    transition: 0.3s;
}
.product-page-item:hover {
    border-left: 5px solid var(--primary);
    transform: translateX(6px);
}
.product-page-item h2 {
    color: var(--dark);
    margin-bottom: 16px;
    font-size: 24px;
}
.product-page-item p {
    color: #555;
    line-height: 1.9;
    font-size: 16px;
}

/* 企业资质 - 图片+文字模式 */
.cert {
    margin-top: 60px;
}
.cert h2 {
    font-size: 28px;
    margin-bottom: 30px;
    text-align: center;
}
.cert-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 25px;
    justify-content: center;
}
.cert-item {
    width: 210px;
    background: #fff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 6px 18px rgba(0,0,0,0.06);
    transition: 0.3s;
}
.cert-item:hover {
    transform: translateY(-6px);
}
.cert-img {
    width: 100%;
    height: 270px;
    padding-top: 10px;
    padding-bottom: 10px;
    padding-left: 10px;
    padding-right: 10px;
    object-fit: cover;
}
.cert-text {
    padding: 12px;
    text-align: center;
    font-size: 15px;
    color: #333;
    font-weight: 500;
}


/* 联系内页 */
.contact-page {
    padding: 100px 5%;
    max-width: 1100px;
    margin: 0 auto;
    display: flex;
    flex-wrap: wrap;
    gap: 60px;
}
.contact-left {
    flex: 1;
    min-width: 300px;
}
.contact-right {
    flex: 1;
    min-width: 300px;
}
.contact-left h2 {
    font-size: 28px;
    margin-bottom: 30px;
    color: var(--dark);
}
.contact-left p {
    font-size: 17px;
    line-height: 2.2;
    color: #333;
    margin-bottom: 10px;
}
input, textarea {
    width: 100%;
    padding: 14px;
    margin-bottom: 16px;
    border: 1px solid #ddd;
    border-radius: 8px;
    font-size: 15px;
}
button {
    padding: 14px 36px;
    background: var(--primary);
    color: #fff;
    border: none;
    border-radius: 8px;
    font-size: 16px;
    cursor: pointer;
    transition: 0.3s;
}
button:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 16px rgba(22,93,255,0.25);
}

/* 页脚 */
.footer {
    background: var(--dark);
    color: #fff;
    text-align: center;
    padding: 45px 20px;
}

/* 移动端 */
@media (max-width: 768px) {
    .banner-slide h1 { font-size: 32px; }
    .section-title { font-size: 28px; }
    .nav-menu a { margin-left: 15px; font-size: 14px; }
    .page-header { font-size: 28px; height: 260px; }
}