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

:root {
    --main: #0F4C81;
    --primary: #2A76BE;
    --dark: #1E293B;
    --light: #f5f7fa;
}

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

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
}

/* 导航 */
.header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 999;
}
.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
}
.logo h2 {
    color: var(--main);
    font-size: 22px;
}
.logo .logo-link {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
}
.logo .logo-text h2 {
    font-size: 20px;
    margin-bottom: 2px;
}
.logo .logo-text p {
    font-size: 10px;
    color: var(--primary);
    letter-spacing: 1px;
}
.logo-icon {
    transition: transform 0.3s;
}
.logo:hover .logo-icon {
    transform: rotate(360deg);
}
.logo p {
    font-size: 12px;
    color: #666;
}
.nav ul {
    display: flex;
    list-style: none;
}
.nav a {
    margin-left: 30px;
    text-decoration: none;
    color: #333;
    font-weight: 500;
}
.nav a:hover {
    color: var(--primary);
}
.mobile-menu {
    display: none;
    font-size: 24px;
    cursor: pointer;
}

/* Banner */
.banner {
    margin-top: 80px;
    background: linear-gradient(135deg, var(--main), var(--primary));
    color: #fff;
    padding: 100px 0;
    text-align: center;
}
.banner h1 {
    font-size: 36px;
    margin-bottom: 20px;
}
.banner p {
    font-size: 18px;
    margin-bottom: 30px;
}
.btns {
    display: flex;
    justify-content: center;
    gap: 20px;
}
.btn {
    padding: 12px 30px;
    border: 1px solid #fff;
    color: #fff;
    text-decoration: none;
    border-radius: 5px;
}
.btn-primary {
    background: #fff;
    color: var(--main);
}

/* 标题通用 */
.title {
    text-align: center;
    margin-bottom: 40px;
}
.title h2 {
    font-size: 28px;
    color: var(--dark);
    margin-bottom: 10px;
}
.title p {
    font-size: 14px;
    color: #999;
    letter-spacing: 2px;
}

/* 关于我们 */
.about {
    padding: 80px 0;
    background: var(--light);
}
.about-content {
    max-width: 900px;
    margin: 0 auto;
    font-size: 16px;
    line-height: 1.8;
    text-align: center;
}
.about-content strong {
    color: var(--main);
}

/* 业务服务 */
.service {
    padding: 80px 0;
}
.service-list {
    display: grid;
    grid-template-columns: repeat(4,1fr);
    gap: 20px;
}
.service-item {
    background: var(--light);
    padding: 30px 20px;
    border-radius: 8px;
    text-align: center;
    transition: 0.3s;
}
.service-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}
.service-item h3 {
    color: var(--main);
    margin-bottom: 10px;
}

/* 解决方案 */
.solution {
    padding: 80px 0;
    background: var(--light);
}
.solution-list {
    display: grid;
    grid-template-columns: repeat(4,1fr);
    gap: 20px;
}
.solution-item {
    background: #fff;
    padding: 30px 20px;
    border-left: 4px solid var(--primary);
    border-radius: 5px;
}

/* 案例 */
.case {
    padding: 80px 0;
}
.case-list {
    display: grid;
    grid-template-columns: repeat(3,1fr);
    gap: 20px;
}
.case-item {
    background: var(--light);
    height: 180px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    color: var(--main);
    font-weight: bold;
}

/* 联系我们 */
.contact {
    padding: 80px 0;
    background: var(--dark);
    color: #fff;
}
.contact .title h2 {
    color: #fff;
}
.contact-info {
    text-align: center;
    font-size: 16px;
    line-height: 2.2;
}

/* 页脚 */
.footer {
    background: #111;
    color: #ccc;
    text-align: center;
    padding: 20px 0;
    font-size: 14px;
}

/* 响应式 */
@media (max-width: 992px) {
    .service-list, .solution-list {
        grid-template-columns: repeat(2,1fr);
    }
    .case-list {
        grid-template-columns: 1fr;
    }
    .floating-ad {
        display: none;
    }
}
@media (max-width: 768px) {
    .nav {
        display: none;
    }
    .mobile-menu {
        display: block;
    }
    .banner h1 {
        font-size: 26px;
    }
}

/* 悬浮广告栏 */
.floating-ad {
    position: fixed;
    top: 50%;
    transform: translateY(-50%);
    z-index: 998;
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.15);
    padding: 15px;
    width: 160px;
    animation: slideIn 0.5s ease;
}
.left-ad {
    left: 20px;
}
.right-ad {
    right: 20px;
}
@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(-50%) translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(-50%) translateX(0);
    }
}
.right-ad {
    animation: slideInRight 0.5s ease;
}
@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateY(-50%) translateX(20px);
    }
    to {
        opacity: 1;
        transform: translateY(-50%) translateX(0);
    }
}
.floating-ad .ad-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    text-align: center;
}
.floating-ad .ad-icon {
    width: 45px;
    height: 45px;
    background: linear-gradient(135deg, #f5f7fa, #e8ecf1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}
.floating-ad .ad-text h4 {
    font-size: 14px;
    color: var(--main);
    margin-bottom: 2px;
}
.floating-ad .ad-text p {
    font-size: 11px;
    color: #666;
}
.floating-ad .ad-btn {
    display: inline-block;
    padding: 6px 20px;
    background: linear-gradient(135deg, var(--main), var(--primary));
    color: #fff;
    text-decoration: none;
    border-radius: 20px;
    font-size: 12px;
    transition: all 0.3s;
}
.floating-ad .ad-btn:hover {
    transform: scale(1.05);
    box-shadow: 0 3px 10px rgba(15, 76, 129, 0.3);
}
.floating-ad .ad-close {
    position: absolute;
    top: -8px;
    right: -8px;
    width: 22px;
    height: 22px;
    background: #999;
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    cursor: pointer;
    transition: background 0.3s;
}
.floating-ad .ad-close:hover {
    background: #666;
}