/* 全局样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    word-wrap: break-word;
    overflow-wrap: break-word;
}

/* 全局container类 - 核心：统一页面容器样式 */
.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

/* 基础样式 */
body {
    font-family: 'Poppins', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
    font-size: 16px;
}

/* ========== 头部样式 ========== */
.header {
    background-color: #1a5293;
    color: white;
    padding: 1rem 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
}

/* LOGO样式 */
.logo {
    flex: 0 0 auto;
    display: flex;
    align-items: center;
}

.logo-link {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: white;
    -webkit-tap-highlight-color: rgba(0,0,0,0);
    tap-highlight-color: rgba(0,0,0,0);
}

.logo-abbr {
    font-size: 1.8rem;
    font-weight: 700;
    letter-spacing: 0.5px;
    color: #ffffff;
    background-color: #2c7ad2;
    padding: 0.3rem 0.8rem;
    border-radius: 4px;
    margin-right: 0.5rem;
    text-transform: uppercase;
}

.logo-full {
    font-size: 1rem;
    font-weight: 500;
    color: #e0e7ff;
    text-transform: uppercase;
    letter-spacing: 0.3px;
}

/* 导航栏样式 */
.nav {
    flex: 1 1 auto;
    display: flex;
    justify-content: center;
    margin: 0 1rem;
}

.nav ul {
    display: flex;
    list-style: none;
    gap: 1.5rem;
    margin: 0;
    padding: 0;
}

.nav a {
    color: white;
    text-decoration: none;
    font-weight: 400;
    transition: color 0.3s;
    padding: 0.5rem 0;
    position: relative;
    -webkit-tap-highlight-color: rgba(0,0,0,0);
    tap-highlight-color: rgba(0,0,0,0);
}

.nav a.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: white;
}

.nav a:hover {
    color: #e0e7ff;
}

/* 语言切换样式 */
.lang-switch {
    flex: 0 0 auto;
    display: flex;
    gap: 0.5rem;
    margin: 0;
}

.lang-btn {
    padding: 0.4rem 0.8rem;
    border: none;
    border-radius: 4px;
    background-color: #2c7ad2;
    color: white;
    cursor: pointer;
    transition: background-color 0.3s;
    font-size: 16px; /* 防止移动端缩放 */
    -webkit-tap-highlight-color: rgba(0,0,0,0);
    tap-highlight-color: rgba(0,0,0,0);
}

.lang-btn.active {
    background-color: #ffffff;
    color: #1a5293;
    font-weight: 500;
}

.lang-btn:hover {
    background-color: #3b88e5;
}

/* ========== 核心页面模块 ========== */
/* 英雄区域 */
.hero {
    background: linear-gradient(135deg, #1a5293 0%, #2c7ad2 100%);
    color: white;
    padding: 5rem 0;
    text-align: center;
}

.hero-content h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    font-weight: 600;
}

.hero-content p {
    font-size: 1.2rem;
    max-width: 800px;
    margin: 0 auto 2rem;
    opacity: 0.9;
}

.btn {
    display: inline-block;
    padding: 0.8rem 2rem;
    background-color: white;
    color: #1a5293;
    text-decoration: none;
    border-radius: 4px;
    font-weight: 500;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    font-size: 16px;
    -webkit-tap-highlight-color: rgba(0,0,0,0);
    tap-highlight-color: rgba(0,0,0,0);
}

.btn:hover {
    background-color: #f0f4ff;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

/* 核心优势 */
.features {
    padding: 4rem 0;
    background-color: white;
}

.features h3 {
    text-align: center;
    font-size: 2rem;
    margin-bottom: 3rem;
    color: #1a5293;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-card {
    background-color: #f8f9fa;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 15px rgba(0,0,0,0.05);
    transition: transform 0.3s, box-shadow 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.1);
}

.feature-card h4 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: #1a5293;
}

/* 通用页面样式 */
.page-content {
    padding: 4rem 0;
    background-color: white;
    min-height: 70vh;
}

.page-title {
    font-size: 2rem;
    color: #1a5293;
    margin-bottom: 2rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #eee;
}

.page-text {
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

.page-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.page-card {
    padding: 1.5rem;
    border-radius: 8px;
    background-color: #f8f9fa;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.page-card h4 {
    color: #1a5293;
    margin-bottom: 1rem;
}

/* 证书页面样式 */
.certificate-container {
    text-align: center;
    margin: 2rem 0;
    padding: 0 1rem;
    width: 100%;
}

.certificate-grid {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
    width: 100%;
    margin: 0 auto;
}

.certificate-img {
    border-radius: 8px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    width: 40%;
    min-width: 280px;
    height: auto;
    object-fit: contain;
    max-width: 100%; /* 强制图片不溢出 */
}

/* 页脚样式 */
.footer {
    background-color: #1a5293;
    color: white;
    padding: 4rem 0 2rem;
    margin-top: 2rem;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-col h4 {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #2c7ad2;
}

.footer-col p {
    margin-bottom: 0.8rem;
    opacity: 0.9;
}

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

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

.footer-col a {
    color: white;
    text-decoration: none;
    opacity: 0.9;
    transition: opacity 0.3s;
    -webkit-tap-highlight-color: rgba(0,0,0,0);
    tap-highlight-color: rgba(0,0,0,0);
}

.footer-col a:hover {
    opacity: 1;
    text-decoration: underline;
}

.copyright {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    opacity: 0.8;
    font-size: 0.9rem;
}

/* ========== 通用移动端优化 ========== */
img {
    max-width: 100%;
    height: auto;
}

input, button, select {
    font-size: 16px; /* 防止移动端输入框缩放 */
}

/* ========== 响应式样式（按屏幕尺寸从大到小） ========== */
/* 大屏适配 (1200px以下) */
@media (max-width: 1200px) {
    .container {
        width: 95%;
        padding: 0 10px;
    }
}

/* 平板端 (992px以下) */
@media (max-width: 992px) {
    /* 头部布局 */
    .header .container {
        flex-direction: column;
        gap: 1rem;
        padding: 0.5rem 10px;
    }
    
    .logo {
        margin-bottom: 0.5rem;
    }
    
    .nav {
        margin: 0;
        width: 100%;
    }
    
    .nav ul {
        justify-content: center;
        gap: 1rem;
    }
    
    /* 英雄区域 */
    .hero {
        padding: 3rem 0;
    }
    
    .hero-content h2 {
        font-size: 2rem;
    }
    
    /* 关于我们页面 */
    .about-intro {
        grid-template-columns: 1fr;
    }
    
    .intro-img {
        order: -1;
        margin-bottom: 1.5rem;
    }
    
    /* 证书页面 */
    .certificate-grid {
        gap: 0.5rem;
    }
    
    /* 页脚 */
    .footer {
        padding: 3rem 0 1.5rem;
    }
}

/* 手机横屏 (768px以下) */
@media (max-width: 768px) {
    /* 基础样式 */
    body {
        font-size: 15px;
    }
    
    /* 头部 */
    .nav ul {
        flex-wrap: wrap;
        row-gap: 0.5rem;
    }
    
    .nav a {
        font-size: 0.9rem;
        padding: 0.3rem 0;
    }
    
    .lang-switch {
        margin-top: 0.5rem;
    }
    
    .lang-btn {
        padding: 0.3rem 0.6rem;
        font-size: 0.9rem;
    }
    
    /* 英雄区域 */
    .hero {
        padding: 2rem 0;
    }
    
    .hero-content h2 {
        font-size: 1.8rem;
    }
    
    .hero-content p {
        font-size: 1rem;
    }
    
    .btn {
        padding: 0.7rem 1.5rem;
        font-size: 0.9rem;
    }
    
    /* 核心优势 */
    .features {
        padding: 2.5rem 0;
    }
    
    .features h3 {
        font-size: 1.8rem;
    }
    
    .feature-card {
        padding: 1.5rem;
    }
    
    /* 通用页面 */
    .page-content {
        padding: 2.5rem 0;
    }
    
    .page-title {
        font-size: 1.8rem;
        margin-bottom: 1.5rem;
    }
    
    /* 关于我们页面 */
    .about-hero {
        padding: 1.5rem 0;
        margin-bottom: 2rem;
    }
    
    .about-hero h1 {
        font-size: 1.8rem;
    }
    
    .about-hero p {
        font-size: 1rem;
    }
    
    .intro-text h2, 
    .about-values h2, 
    .office-gallery h2, 
    .contact-info h2 {
        font-size: 1.5rem;
    }
    
    .value-card {
        padding: 1.5rem;
    }
    
    /* 证书页面 */
    .certificate-grid {
        flex-direction: column;
        gap: 1rem;
    }
    .certificate-img {
        width: 80%;
        min-width: unset;
    }
    
    /* 联系信息 */
    .contact-info {
        padding: 1.5rem;
    }
}

/* 手机竖屏 (576px以下) */
@media (max-width: 576px) {
    /* LOGO简化 */
    .logo-abbr {
        font-size: 1.5rem;
        padding: 0.2rem 0.6rem;
    }
    
    .logo-full {
        font-size: 0.8rem;
    }
    
    /* 导航栏 */
    .nav ul {
        gap: 0.8rem;
    }
    
    .nav a {
        font-size: 0.85rem;
    }
    
    /* 英雄区域 */
    .hero-content h2 {
        font-size: 1.6rem;
        line-height: 1.4;
    }
    
    /* 核心优势 */
    .features-grid {
        gap: 1rem;
    }
    
    .feature-card h4 {
        font-size: 1.2rem;
    }
    
    /* 通用页面 */
    .page-text {
        font-size: 0.95rem;
        line-height: 1.7;
    }
    
    /* 办公场所图片 */
    .gallery-item img {
        height: 200px;
    }
    
    .gallery-item p {
        font-size: 0.9rem;
        padding: 0.8rem;
    }
    
    /* 联系信息 */
    .contact-grid {
        gap: 1rem;
    }
    
    .contact-item h3 {
        font-size: 1rem;
    }
    
    .contact-item p {
        font-size: 0.9rem;
    }
    
    /* 页脚 */
    .footer-grid {
        gap: 1.5rem;
    }
    
    .footer-col h4 {
        font-size: 1.1rem;
    }
    
    .footer-col p, .footer-col a {
        font-size: 0.9rem;
    }
    
    .copyright {
        font-size: 0.8rem;
        padding-top: 1.5rem;
    }
    
    /* 通用页面标题 */
    .features h3, .page-title {
        font-size: 1.6rem;
    }
}

/* 超小屏 (480px以下) */
@media (max-width: 480px) {
    /* 导航栏进一步简化 */
    .nav ul {
        gap: 0.5rem;
    }
    
    .nav a {
        font-size: 0.8rem;
        padding: 0.2rem 0;
    }
    
    /* 按钮适配 */
    .btn {
        width: 100%;
        max-width: 300px;
        display: block;
        margin: 0 auto;
    }
    
    /* 证书图片 */
    .certificate-img {
        width: 90%;
    }
    
    /* 办公图片 */
    .gallery-item img {
        height: 180px;
    }
}