/* 基础样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary-color: #06b6d4;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --bg-light: #f9fafb;
    --bg-white: #ffffff;
    --border-color: #e5e7eb;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --transition: all 0.3s ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-white);
}

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

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.98);
    box-shadow: var(--shadow);
    z-index: 1000;
    transition: var(--transition);
}

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

.nav-brand .logo {
    height: 50px;
    width: auto;
    display: block;
}

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

.nav-link {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: var(--transition);
    padding: 0.5rem 0;
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 4px;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--text-dark);
    transition: var(--transition);
}

/* 首页横幅 */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 100px 20px 60px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    overflow: hidden;
}

.hero-content {
    position: relative;
    z-index: 2;
    color: white;
    max-width: 800px;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    line-height: 1.3;
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 300;
    margin-bottom: 1rem;
    opacity: 0.95;
}

.hero-description {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><circle cx="50" cy="50" r="40" fill="none" stroke="rgba(255,255,255,0.1)" stroke-width="0.5"/></svg>');
    background-size: 100px 100px;
    opacity: 0.3;
}

/* 按钮样式 */
.btn {
    display: inline-block;
    padding: 12px 32px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background: white;
    color: var(--primary-color);
}

.btn-primary:hover {
    background: var(--bg-light);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-block {
    width: 100%;
}

/* 通用区块样式 */
.section {
    padding: 80px 0;
}

.section-title {
    text-align: center;
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 3rem;
    color: var(--text-dark);
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
}

/* 关于我们 */
.about {
    background: var(--bg-light);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-text p {
    margin-bottom: 1.5rem;
    color: var(--text-light);
    line-height: 1.8;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.stat-item {
    text-align: center;
    padding: 2rem;
    background: white;
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.stat-label {
    color: var(--text-light);
    font-size: 0.9rem;
}

/* 主营业务 */
.services {
    background: white;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.service-card {
    background: var(--bg-light);
    padding: 2.5rem;
    border-radius: 12px;
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.service-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.service-icon {
    font-size: 3rem;
    margin-bottom: 1.5rem;
}

.service-card h3 {
    font-size: 1.3rem;
    margin-bottom: 1.5rem;
    color: var(--text-dark);
}

.service-card ul {
    list-style: none;
}

.service-card li {
    padding: 0.5rem 0;
    color: var(--text-light);
    padding-left: 1.5rem;
    position: relative;
}

.service-card li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: 700;
}

/* 核心优势 */
.advantages {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
}

.advantage-item {
    text-align: center;
    padding: 2rem;
    background: white;
    border-radius: 12px;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.advantage-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.advantage-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.advantage-item h4 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--text-dark);
}

.advantage-item p {
    color: var(--text-light);
    font-size: 0.9rem;
    line-height: 1.6;
}

/* 联系我们 */
.contact {
    background: white;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
}

.contact-icon {
    font-size: 2rem;
    flex-shrink: 0;
}

.contact-item h4 {
    font-size: 1.1rem;
    margin-bottom: 0.3rem;
    color: var(--text-dark);
}

.contact-item p {
    color: var(--text-light);
}

.contact-form {
    background: var(--bg-light);
    padding: 2.5rem;
    border-radius: 12px;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
    transition: var(--transition);
    background: white;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-group textarea {
    resize: vertical;
}

/* 页脚 */
.footer {
    background: var(--text-dark);
    color: white;
    padding: 3rem 0 1.5rem;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 2rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    margin-bottom: 1.5rem;
}

.footer-brand h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.footer-brand p {
    opacity: 0.7;
    font-size: 0.9rem;
}

.footer-links {
    display: flex;
    gap: 2rem;
}

.footer-links a {
    color: white;
    text-decoration: none;
    opacity: 0.7;
    transition: var(--transition);
}

.footer-links a:hover {
    opacity: 1;
}

.footer-bottom {
    text-align: center;
    opacity: 0.7;
    font-size: 0.9rem;
}

.footer-bottom p {
    margin: 0.3rem 0;
}

/* 响应式设计 */
@media (max-width: 968px) {
    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1.2rem;
    }

    .about-content,
    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .services-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .advantages-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .about-stats {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 2rem;
        gap: 1rem;
        box-shadow: var(--shadow);
        transform: translateY(-150%);
        transition: var(--transition);
    }

    .nav-menu.active {
        transform: translateY(0);
    }

    .hamburger {
        display: flex;
    }

    .services-grid {
        grid-template-columns: 1fr;
    }

    .advantages-grid {
        grid-template-columns: 1fr;
    }

    .footer-content {
        flex-direction: column;
        gap: 2rem;
        text-align: center;
    }

    .footer-links {
        flex-wrap: wrap;
        justify-content: center;
    }

    .hero-title {
        font-size: 1.8rem;
    }

    .section-title {
        font-size: 1.5rem;
    }
}

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

.hero-content {
    animation: fadeInUp 1s ease-out;
}

.service-card,
.advantage-item,
.stat-item {
    animation: fadeInUp 0.6s ease-out backwards;
}

.service-card:nth-child(1) { animation-delay: 0.1s; }
.service-card:nth-child(2) { animation-delay: 0.2s; }
.service-card:nth-child(3) { animation-delay: 0.3s; }

.advantage-item:nth-child(1) { animation-delay: 0.1s; }
.advantage-item:nth-child(2) { animation-delay: 0.2s; }
.advantage-item:nth-child(3) { animation-delay: 0.3s; }
.advantage-item:nth-child(4) { animation-delay: 0.4s; }