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

body {
    line-height: 1.7;
    color: #333;
    background-color: #f5f7fa;
}

/* 导航栏-置顶+深色主题+科技感 */
.nav {
    background-color: #165DFF;
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.nav-container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    color: #fff;
    font-size: 1.6rem;
    font-weight: bold;
    text-decoration: none;
}

.nav-menu {
    display: flex;
    list-style: none;
}

.nav-menu li {
    margin-left: 2.2rem;
}

.nav-menu a {
    color: #fff;
    text-decoration: none;
    font-size: 1rem;
    transition: color 0.3s;
}

.nav-menu a:hover {
    color: #c9e0ff;
}

/* 通用容器样式 */
.container {
    width: 90%;
    max-width: 1200px;
    margin: 2rem auto;
    padding: 2rem;
    background-color: #fff;
    border-radius: 10px;
    box-shadow: 0 0 15px rgba(0,0,0,0.05);
}

/* 首页banner-科技感主视觉 */
.banner {
    height: 400px;
    background: linear-gradient(rgba(22, 93, 255, 0.8), rgba(22, 93, 255, 0.8)), url('../images/banner.jpg');
    background-size: cover;
    background-position: center;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    text-align: center;
}

.banner h2 {
    font-size: 2.8rem;
    margin-bottom: 1.2rem;
    font-weight: bold;
}

.banner p {
    font-size: 1.25rem;
    max-width: 900px;
    line-height: 1.8;
}

/* 板块标题样式-科技蓝主题 */
.section-title {
    font-size: 2rem;
    color: #165DFF;
    margin-bottom: 1.5rem;
    border-bottom: 3px solid #e6f0ff;
    padding-bottom: 0.6rem;
    font-weight: 600;
}

/* 业务卡片样式-悬浮动效+科技感边框 */
.business-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.business-item {
    padding: 2rem 1.8rem;
    border: 1px solid #e6f0ff;
    border-radius: 10px;
    background-color: #fbfdff;
    transition: transform 0.3s, box-shadow 0.3s;
}

.business-item:hover {
    transform: translateY(-6px);
    box-shadow: 0 8px 20px rgba(22,93,255,0.12);
    border-color: #165DFF;
}

.business-item h3 {
    color: #165DFF;
    margin-bottom: 1.2rem;
    font-size: 1.4rem;
}

/* 页脚样式 */
.footer {
    background-color: #165DFF;
    color: #fff;
    text-align: center;
    padding: 2rem 0;
    margin-top: 4rem;
}

.footer p {
    line-height: 1.8;
}

/* 响应式适配-手机端自动调整布局 */
@media (max-width: 768px) {
    .nav-container {
        flex-direction: column;
    }
    .nav-menu {
        margin-top: 1rem;
        flex-wrap: wrap;
        justify-content: center;
    }
    .nav-menu li {
        margin: 0.5rem 1rem;
    }
    .banner {
        height: 300px;
    }
    .banner h2 {
        font-size: 2rem;
    }
    .section-title {
        font-size: 1.6rem;
    }
}