/* 基础重置与变量定义 */
:root {
    --primary-color: #1a365d; /* 深蓝，体现专业与稳重 */
    --secondary-color: #4fd1c5; /* 青绿色，体现活力与创新 */
    --accent-color: #ed8936; /* 橙色，用于强调 */
    --light-color: #f7fafc;
    --dark-color: #2d3748;
    --text-color: #2d3748;
    --text-light: #718096;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
    --border-radius: 8px;
    --max-width: 1200px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--light-color);
    overflow-x: hidden;
}

.lang-zh { display: block; }
.lang-en { display: none; }

body.lang-en .lang-zh { display: none; }
body.lang-en .lang-en { display: block; }

/* 容器 */
.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* 按钮 */
.btn {
    display: inline-block;
    padding: 12px 28px;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: var(--border-radius);
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    text-align: center;
}

.btn:hover {
    background-color: #2c5282;
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.btn-outline {
    background-color: transparent;
    border: 2px solid var(--primary-color);
    color: var(--primary-color);
}

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

/* 语言切换器 */
.lang-switcher {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
    background: white;
    border-radius: 50px;
    padding: 5px;
    box-shadow: var(--shadow);
    display: flex;
}

.lang-btn {
    padding: 8px 16px;
    border: none;
    background: none;
    border-radius: 50px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

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

/* 导航栏 */
header {
    background-color: white;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 999;
    padding: 15px 0;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    text-decoration: none;
}

.logo-icon {
    font-size: 24px;
    color: var(--primary-color);
    margin-right: 10px;
}

.logo-text {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary-color);
}

.logo-text .sub {
    font-size: 12px;
    color: var(--text-light);
    font-weight: 400;
    display: block;
    line-height: 1.2;
}

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

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

.nav-links a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 600;
    transition: var(--transition);
    position: relative;
}

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

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: width 0.3s ease;
}

.nav-links a:hover::after {
    width: 100%;
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 24px;
    color: var(--primary-color);
    cursor: pointer;
}

/* 英雄区域 */
.hero {
    padding: 100px 0 80px;
    background: linear-gradient(135deg, #f6f9fc 0%, #ffffff 100%);
    text-align: center;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 20px;
    color: var(--primary-color);
    line-height: 1.2;
}

.hero p {
    font-size: 1.2rem;
    max-width: 800px;
    margin: 0 auto 40px;
    color: var(--text-light);
}

.hero-btns {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

/* 公司简介 */
.about {
    padding: 80px 0;
    background-color: white;
}

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

.section-title h2 {
    font-size: 2.5rem;
    color: var(--primary-color);
    display: inline-block;
    padding-bottom: 15px;
}

.section-title h2::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 3px;
    background-color: var(--secondary-color);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.about-text p {
    margin-bottom: 20px;
    font-size: 1.1rem;
}

.about-highlights {
    background-color: #f8f9fa;
    border-radius: var(--border-radius);
    padding: 30px;
    box-shadow: var(--shadow);
}

.highlight-item {
    display: flex;
    align-items: flex-start;
    margin-bottom: 25px;
}

.highlight-icon {
    background-color: var(--secondary-color);
    color: white;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 15px;
    flex-shrink: 0;
}

.highlight-text h4 {
    margin-bottom: 5px;
    color: var(--primary-color);
}

/* 业务范围 */
.services {
    padding: 80px 0;
    background-color: #f8f9fa;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
}

.service-card {
    background-color: white;
    border-radius: var(--border-radius);
    padding: 30px;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

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

.service-icon {
    font-size: 2.5rem;
    color: var(--secondary-color);
    margin-bottom: 20px;
}

.service-card h3 {
    margin-bottom: 15px;
    color: var(--primary-color);
}

.service-card p {
    color: var(--text-light);
}

/* 公司理念 */
.philosophy {
    padding: 80px 0;
    background-color: white;
}

.philosophy-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.philosophy-content p {
    font-size: 1.2rem;
    line-height: 1.8;
    margin-bottom: 30px;
    font-style: italic;
    color: var(--text-color);
}

.quote-author {
    color: var(--text-light);
    font-weight: 600;
}

/* 联系信息 */
.contact {
    padding: 80px 0;
    background-color: var(--primary-color);
    color: white;
}

.contact .section-title h2 {
    color: white;
}

.contact .section-title h2::after {
    background-color: var(--secondary-color);
}

.contact-info {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    text-align: center;
}

.contact-item {
    padding: 20px;
}

.contact-icon {
    font-size: 2.5rem;
    color: var(--secondary-color);
    margin-bottom: 20px;
}

.contact-item h3 {
    margin-bottom: 10px;
    font-size: 1.3rem;
}

.contact-item p {
    opacity: 0.9;
}

/* 页脚 */
footer {
    background-color: var(--dark-color);
    color: white;
    padding: 40px 0 20px;
    text-align: center;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    margin-bottom: 30px;
}

.footer-logo {
    font-size: 24px;
    font-weight: 700;
    color: white;
}

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

.footer-links li {
    margin-left: 20px;
}

.footer-links a {
    color: #cbd5e0;
    text-decoration: none;
    transition: var(--transition);
}

.footer-links a:hover {
    color: white;
}

.copyright {
    padding-top: 20px;
    border-top: 1px solid #4a5568;
    color: #a0aec0;
    font-size: 0.9rem;
}

/* 响应式设计 */
@media (max-width: 992px) {
    .about-content {
        grid-template-columns: 1fr;
    }

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

@media (max-width: 768px) {
    .mobile-menu-btn {
        display: block;
    }

    .nav-links {
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        background-color: white;
        flex-direction: column;
        align-items: center;
        padding: 20px 0;
        box-shadow: var(--shadow);
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: var(--transition);
    }

    .nav-links.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }

    .nav-links li {
        margin: 15px 0;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero-btns {
        flex-direction: column;
        align-items: center;
    }

    .footer-content {
        flex-direction: column;
        gap: 20px;
    }

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

    .footer-links li {
        margin: 0 10px;
    }
}

@media (max-width: 576px) {
    .hero {
        padding: 80px 0 60px;
    }

    .section-title h2 {
        font-size: 2rem;
    }

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