/* 全局样式 */
:root {
    --primary-blue: #1a237e;
    --primary-orange: #ff6b00;
    --gradient-primary: linear-gradient(135deg, #1a237e 0%, #ff6b00 100%);
    --gradient-hover: linear-gradient(135deg, #ff6b00 0%, #1a237e 100%);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

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

/* 页眉样式 */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: #fff;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    z-index: 1000;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

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

.logo-img {
    height: 50px;
    margin-right: 1rem;
}

.logo h1 {
    font-size: 1.5rem;
    color: var(--primary-blue);
}

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

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

.nav-links a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s ease;
    padding: 0.5rem 0;
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--gradient-primary);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

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

.nav-links a:hover::after,
.nav-links a.active::after {
    transform: scaleX(1);
}

/* 页脚样式 */
footer {
    background-color: #1a237e;
    color: #fff;
    padding: 3rem 2rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.contact-info h3,
.footer-links h3 {
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

.contact-info p {
    margin-bottom: 0.5rem;
}

.footer-links ul {
    list-style: none;
}

.footer-links li {
    margin-bottom: 0.5rem;
}

.footer-links a {
    color: #fff;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: var(--primary-orange);
}

.copyright {
    max-width: 1200px;
    margin: 2rem auto 0;
    padding-top: 1rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    text-align: center;
    font-size: 0.9rem;
}

/* 通用标题样式 */
.section-title {
    text-align: center;
    margin-bottom: 3rem;
}

.section-title h2 {
    font-size: 2.5rem;
    color: var(--primary-blue);
    margin-bottom: 1rem;
    position: relative;
    display: inline-block;
}

.section-title h2::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: var(--gradient-primary);
    border-radius: 2px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    nav {
        flex-direction: column;
        padding: 1rem;
    }
    
    .logo {
        margin-bottom: 1rem;
    }
    
    .nav-links {
        width: 100%;
        justify-content: space-around;
    }
    
    .nav-links li {
        margin: 0;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
    }
}