/* 全局样式 */
:root {
    --primary-color: #0056b3;
    --secondary-color: #6c757d;
    --dark-color: #343a40;
    --light-color: #f8f9fa;
    --text-color: #333;
    --white: #ffffff;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--white);
}

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

a {
    text-decoration: none;
    color: inherit;
    transition: 0.3s;
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
}

.section {
    padding: 80px 0;
}

.bg-light {
    background-color: var(--light-color);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 50px;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: var(--primary-color);
    margin: 15px auto 0;
}

.btn {
    display: inline-block;
    padding: 12px 30px;
    background: var(--primary-color);
    color: var(--white);
    border-radius: 5px;
    font-weight: bold;
    border: none;
    cursor: pointer;
    transition: 0.3s;
}

.btn:hover {
    background: #004494;
    transform: translateY(-2px);
}

/* 导航栏 */
header {
    background: var(--white);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
}

nav {
    height: 80px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

.nav-links {
    display: flex;
}

.nav-links li {
    margin-left: 30px;
}

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

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

/* 英雄页 */
.hero {
    height: 100vh;
    background: linear-gradient(rgba(0,0,0,0.6), rgba(0,0,0,0.6)), url('https://images.unsplash.com/photo-1451187580459-43490279c0fa?ixlib=rb-1.2.1&auto=format&fit=crop&w=1352&q=80') no-repeat center center/cover;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--white);
    padding-top: 80px;
}

.hero-content h1 {
    font-size: 3.5rem;
    margin-bottom: 20px;
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 30px;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

/* 关于我们 */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.about-text p {
    margin-bottom: 20px;
}

.feature-item {
    display: flex;
    align-items: center;
    margin-bottom: 15px;
    font-size: 1.1rem;
}

.feature-item i {
    color: #28a745;
    margin-right: 15px;
    font-size: 1.5rem;
}

/* 核心业务 */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.service-card {
    background: var(--white);
    padding: 40px;
    border-radius: 10px;
    text-align: center;
    box-shadow: 0 5px 15px rgba(0,0,0,0.05);
    transition: 0.3s;
}

.service-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.1);
}

.service-card i {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 20px;
}

.service-card h3 {
    margin-bottom: 15px;
}

/* 联系我们 */
.contact-container {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 50px;
}

.info-item {
    display: flex;
    align-items: center;
    margin-bottom: 30px;
}

.info-item i {
    width: 50px;
    height: 50px;
    background: var(--light-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary-color);
    margin-right: 20px;
    font-size: 1.2rem;
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 12px;
    margin-bottom: 20px;
    border: 1px solid #ddd;
    border-radius: 5px;
    outline: none;
}

.contact-form input:focus,
.contact-form textarea:focus {
    border-color: var(--primary-color);
}

/* 页脚 */
footer {
    background: var(--dark-color);
    color: var(--white);
    padding: 40px 0;
    text-align: center;
}

.footer-links {
    margin-top: 20px;
}

.footer-links a {
    color: #ccc;
    font-size: 0.9rem;
}

.footer-links a:hover {
    color: var(--white);
    text-decoration: underline;
}

/* 响应式 */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .menu-toggle {
        display: block;
    }

    .hero-content h1 {
        font-size: 2.5rem;
    }

    .about-grid, .contact-container {
        grid-template-columns: 1fr;
    }
}