/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    color: #333;
}

/* 导航栏样式 */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 5%;
    background-color: #fff;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    width: 100%;
    z-index: 1000;
}

.logo {
    display: flex;
    align-items: center;
}

.logo h1 {
    color: #2c3e50;
    font-size: 1.5rem;
}

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

.nav-links li {
    margin-left: 2rem;
}

.nav-links a {
    text-decoration: none;
    color: #2c3e50;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: #3498db;
}

.menu-toggle {
    display: none;
    font-size: 1.5rem;
    cursor: pointer;
}

/* 章节通用样式 */
section {
    padding: 4rem 10%;
}

section:first-of-type {
    padding-top: 6rem;
}

section h2 {
    text-align: center;
    margin-bottom: 3rem;
    color: #2c3e50;
    font-size: 2.2rem;
}

/* 关于我们样式 */
.about-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.about-text {
    margin-bottom: 2rem;
    padding: 1.5rem;
    background: #f8f9fa;
    border-radius: 10px;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.about-text::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(
        90deg,
        transparent,
        rgba(52, 152, 219, 0.2),
        transparent
    );
    transition: 0.5s;
}

.about-text:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.about-text:hover::before {
    left: 100%;
}

/* 服务卡片样式 */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.service-card {
    background: #fff;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 3px 10px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
    text-align: center;
}

.service-card:hover {
    transform: translateY(-5px);
}

.service-card i {
    font-size: 2.5rem;
    color: #3498db;
    margin-bottom: 1rem;
}

.service-card h3 {
    color: #2c3e50;
    margin-bottom: 1rem;
}

/* 项目案例样式 */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.project-card {
    background: #fff;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 3px 10px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
}

.project-card:hover {
    transform: translateY(-5px);
}

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

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

.project-card h3 {
    color: #2c3e50;
    margin-bottom: 0.5rem;
}

.project-card p {
    color: #666;
}

/* 页脚样式 */
footer {
    background-color: #2c3e50;
    color: white;
    padding: 3rem 5%;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
}

.copyright {
    padding-top: 1rem;
    border-top: 1px solid rgba(255,255,255,0.1);
}

/* 返回顶部按钮 */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background: #3498db;
    color: white;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: none;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    transition: background-color 0.3s ease;
    z-index: 1000;
}

.back-to-top:hover {
    background: #2980b9;
}

/* 动画 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .menu-toggle {
        display: block;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: white;
        padding: 1rem;
        box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    }

    .nav-links.active {
        display: flex;
        flex-direction: column;
    }

    .nav-links li {
        margin: 0.5rem 0;
    }
    
    section {
        padding: 3rem 5%;
    }
    
    section:first-of-type {
        padding-top: 5rem;
    }
    
    section h2 {
        font-size: 1.8rem;
    }
    
    .services-grid,
    .projects-grid {
        grid-template-columns: 1fr;
    }
}

/* 占位图样式 */
.hero-placeholder {
    height: 60vh;
    background: linear-gradient(135deg, #b38fec, #2c3e50);
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: white;
    padding: 0 1rem;
    margin-bottom: 2rem;
}

.placeholder-content {
    max-width: 800px;
    margin: 0 auto;
}

.placeholder-content h2 {
    font-size: 3rem;
    margin-bottom: 1.5rem;
    animation: fadeInUp 1s ease;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.placeholder-content p {
    font-size: 1.4rem;
    margin-bottom: 2rem;
    animation: fadeInUp 1s ease 0.3s;
    animation-fill-mode: both;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.3);
}