/* 重置样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Microsoft YaHei', 'SimHei', sans-serif;
    line-height: 1.6;
    color: #2d3748;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部导航 */
header {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    transition: all 0.3s ease;
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.logo a {
    font-size: 1.5rem;
    font-weight: bold;
    color: #1a365d;
    text-decoration: none;
}

nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

nav ul li {
    position: relative;
}

nav a {
    color: #4a5568;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

nav ul .dropdown > a {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

nav ul .dropdown > a::after {
    content: '\25BE';
    font-size: 0.65rem;
    color: #a0aec0;
    transition: transform 0.3s ease, color 0.3s ease;
}

nav ul .dropdown:hover > a::after,
nav ul .dropdown:focus-within > a::after {
    transform: rotate(180deg);
    color: #d69e2e;
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 200px;
    background: #ffffff;
    border-radius: 12px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.12);
    padding: 12px 0;
    opacity: 0;
    visibility: hidden;
    transform: translateY(12px);
    transition: all 0.25s ease;
    pointer-events: none;
    z-index: 999;
}

nav ul .dropdown:hover .dropdown-menu,
nav ul .dropdown:focus-within .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    pointer-events: auto;
}

.dropdown-menu li {
    list-style: none;
}

.dropdown-menu a {
    display: block;
    padding: 10px 20px;
    color: #2d3748;
    font-weight: 500;
    text-decoration: none;
    transition: background 0.3s ease, color 0.3s ease;
}

.dropdown-menu a:hover {
    background: rgba(214, 158, 46, 0.12);
    color: #1a365d;
}

nav a:hover {
    color: #d69e2e;
}

/* 主视觉区 */
#hero {
    position: relative;
    height: 100vh;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #1a365d, #274b7a);
}

#hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(26, 54, 93, 0.85), rgba(214, 158, 46, 0.45));
    z-index: 0;
}

#hero-video {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    z-index: -1;
}

.hero-content {
    text-align: center;
    color: white;
    z-index: 1;
    background: rgba(10, 26, 52, 0.55);
    padding: 3rem;
    border-radius: 10px;
}

.hero-content h1 {
    font-size: 4rem;
    margin-bottom: 1rem;
    animation: fadeInUp 1s ease;
}

.hero-content p {
    font-size: 1.5rem;
    margin-bottom: 2rem;
    animation: fadeInUp 1s ease 0.3s both;
}

.btn {
    display: inline-block;
    background: #d69e2e;
    color: white;
    padding: 1rem 2rem;
    text-decoration: none;
    border-radius: 5px;
    font-weight: bold;
    transition: all 0.3s ease;
    animation: fadeInUp 1s ease 0.6s both;
}

.btn:hover {
    background: #b7791f;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(214, 158, 46, 0.4);
}

/* 关于我们 */
#about {
    padding: 5rem 0;
    background: #f7fafc;
}

#about h2 {
    text-align: center;
    font-size: 2.5rem;
    color: #1a365d;
    margin-bottom: 3rem;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.about-text p {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    line-height: 1.8;
}

.stats {
    display: flex;
    gap: 2rem;
}

.stat {
    text-align: center;
}

.stat .count {
    display: block;
    font-size: 2rem;
    font-weight: bold;
    color: #d69e2e;
}

.about-image img {
    width: 100%;
    border-radius: 10px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

/* 核心业务 */
#services {
    padding: 5rem 0;
}

#services h2 {
    text-align: center;
    font-size: 2.5rem;
    color: #1a365d;
    margin-bottom: 3rem;
}

.service-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.service-card {
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

.service-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
}

.service-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.service-card-content {
    padding: 1.5rem;
}

.service-card h3 {
    color: #1a365d;
    margin-bottom: 1rem;
}

.service-card p {
    color: #4a5568;
    margin-bottom: 1rem;
}

.service-card a {
    color: #d69e2e;
    text-decoration: none;
    font-weight: bold;
}

/* 项目案例 */
#projects {
    padding: 5rem 0;
    background: #f7fafc;
}

#projects h2 {
    text-align: center;
    font-size: 2.5rem;
    color: #1a365d;
    margin-bottom: 3rem;
}

.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.project-card {
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

.project-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
}

.project-card img {
    width: 100%;
    height: 250px;
    object-fit: cover;
}

.project-card-content {
    padding: 1.5rem;
}

.project-card h3 {
    color: #1a365d;
    margin-bottom: 0.5rem;
}

.project-card .project-type {
    color: #d69e2e;
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.project-card p {
    color: #4a5568;
}

/* 我们的优势 */
#strengths {
    padding: 5rem 0;
    background: linear-gradient(135deg, #1a365d, #2d3748);
    color: white;
}

#strengths h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
}

.strength-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.strength-item {
    text-align: center;
    padding: 2rem;
}

.strength-item img {
    width: 64px;
    height: 64px;
    margin-bottom: 1rem;
}

.strength-item h3 {
    margin-bottom: 1rem;
    color: #d69e2e;
}

/* 新闻中心 */
#news {
    padding: 5rem 0;
}

#news h2 {
    text-align: center;
    font-size: 2.5rem;
    color: #1a365d;
    margin-bottom: 3rem;
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.news-card {
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

.news-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.15);
}

.news-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.news-card-content {
    padding: 1.5rem;
}

.news-card .date {
    color: #d69e2e;
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.news-card h3 {
    color: #1a365d;
    margin-bottom: 1rem;
}

.news-card p {
    color: #4a5568;
    margin-bottom: 1rem;
}

.news-card a {
    color: #d69e2e;
    text-decoration: none;
    font-weight: bold;
}

/* 合作伙伴 */
#partners {
    padding: 3rem 0;
    background: #f7fafc;
}

#partners h2 {
    text-align: center;
    font-size: 2.5rem;
    color: #1a365d;
    margin-bottom: 3rem;
}

.partner-logos {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 3rem;
    flex-wrap: wrap;
}

.partner-logos img {
    height: 60px;
    opacity: 0.7;
    transition: opacity 0.3s ease;
}

.partner-logos img:hover {
    opacity: 1;
}

/* 联系我们 */
#contact {
    padding: 5rem 0;
}

#contact h2 {
    text-align: center;
    font-size: 2.5rem;
    color: #1a365d;
    margin-bottom: 3rem;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
}

.contact-info p {
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.contact-form {
    background: #f7fafc;
    padding: 2rem;
    border-radius: 10px;
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 1rem;
    margin-bottom: 1rem;
    border: 1px solid #e2e8f0;
    border-radius: 5px;
    font-size: 1rem;
}

.contact-form textarea {
    height: 120px;
    resize: vertical;
}

/* 页脚 */
footer {
    background: #2d3748;
    color: white;
    text-align: center;
    padding: 2rem 0;
}

/* 动画 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .hero-content h1 {
        font-size: 2.5rem;
    }
    
    .hero-content p {
        font-size: 1.2rem;
    }
    
    .about-content {
        grid-template-columns: 1fr;
    }
    
    .stats {
        justify-content: center;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
    }
    
    nav ul {
        display: none;
    }
    
    .service-grid,
    .project-grid,
    .news-grid {
        grid-template-columns: 1fr;
    }
    
    .strength-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero-content {
        padding: 2rem;
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .strength-grid {
        grid-template-columns: 1fr;
    }
}