/* ========================================
   ACADTECH - 全局样式
   ======================================== */

:root {
    --primary-dark: #0A2463;
    --primary: #1E3A8A;
    --secondary: #3E92CC;
    --accent: #0EA5E9;
    --text-dark: #1F2937;
    --text-gray: #6B7280;
    --text-light: #9CA3AF;
    --bg-light: #F9FAFB;
    --bg-white: #FFFFFF;
    --border: #E5E7EB;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --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);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --radius: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
}

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

html {
    scroll-behavior: smooth;
}

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

/* ========================================
   布局容器
   ======================================== */

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.container-sm {
    max-width: 1000px;
}

/* ========================================
   头部导航
   ======================================== */

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
    transition: all 0.3s ease;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    color: var(--text-dark);
}

.logo-img {
    height: 40px;
    width: auto;
}

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

.nav {
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-link {
    padding: 8px 16px;
    text-decoration: none;
    color: var(--text-gray);
    font-weight: 500;
    border-radius: var(--radius);
    transition: all 0.2s ease;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary);
    background: rgba(30, 58, 138, 0.05);
}

.lang-switcher {
    display: flex;
    gap: 4px;
    margin-left: 16px;
    padding-left: 16px;
    border-left: 1px solid var(--border);
}

.lang-btn {
    padding: 6px 12px;
    border: 1px solid var(--border);
    background: var(--bg-white);
    color: var(--text-gray);
    font-size: 14px;
    font-weight: 500;
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.2s ease;
}

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

.mobile-menu-btn {
    display: none;
    padding: 8px;
    background: none;
    border: none;
    cursor: pointer;
}

/* ========================================
   Hero 区域
   ======================================== */

.hero {
    margin-top: 72px;
    padding: 120px 0;
    background: linear-gradient(135deg, #0A2463 0%, #1E3A8A 50%, #3E92CC 100%);
    color: white;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><defs><pattern id="grid" width="100" height="100" patternUnits="userSpaceOnUse"><path d="M 100 0 L 0 0 0 100" fill="none" stroke="rgba(255,255,255,0.05)" stroke-width="1"/></pattern></defs><rect width="100%" height="100%" fill="url(%23grid)" /></svg>');
    opacity: 0.5;
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 900px;
    margin: 0 auto;
}

.hero-title {
    font-size: 48px;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 24px;
}

.hero-subtitle {
    font-size: 18px;
    line-height: 1.8;
    opacity: 0.9;
    margin-bottom: 40px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

/* ========================================
   按钮
   ======================================== */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 32px;
    font-size: 16px;
    font-weight: 600;
    text-decoration: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    border: none;
    transition: all 0.3s ease;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid rgba(255, 255, 255, 0.5);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: white;
}

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

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

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

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

/* ========================================
   Section 通用样式
   ======================================== */

.section {
    padding: 100px 0;
}

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

.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-title {
    font-size: 36px;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 16px;
}

.section-subtitle {
    font-size: 18px;
    color: var(--text-gray);
    max-width: 700px;
    margin: 0 auto;
}

/* ========================================
   品牌介绍
   ======================================== */

.brand-intro {
    text-align: center;
    max-width: 900px;
    margin: 0 auto;
}

.brand-intro h2 {
    font-size: 32px;
    font-weight: 700;
    color: var(--primary-dark);
    margin-bottom: 24px;
}

.brand-intro p {
    font-size: 18px;
    color: var(--text-gray);
    line-height: 1.8;
}

/* ========================================
   卡片网格
   ======================================== */

.card-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

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

.card-grid-4 {
    grid-template-columns: repeat(4, 1fr);
}

.card {
    background: var(--bg-white);
    border-radius: var(--radius-xl);
    padding: 32px;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
}

.card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
}

.card-icon {
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    color: white;
    font-size: 24px;
}

.card-title {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 12px;
}

.card-text {
    font-size: 15px;
    color: var(--text-gray);
    line-height: 1.7;
}

/* ========================================
   优势列表
   ======================================== */

.advantage-list {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 24px;
}

.advantage-item {
    text-align: center;
    padding: 24px 16px;
}

.advantage-icon {
    width: 64px;
    height: 64px;
    background: var(--bg-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 16px;
    font-size: 28px;
}

.advantage-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 8px;
}

.advantage-text {
    font-size: 14px;
    color: var(--text-gray);
    line-height: 1.6;
}

/* ========================================
   CTA 区域
   ======================================== */

.cta-section {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 100%);
    color: white;
    text-align: center;
    padding: 80px 0;
    border-radius: var(--radius-xl);
}

.cta-title {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 16px;
}

.cta-text {
    font-size: 18px;
    opacity: 0.9;
    margin-bottom: 32px;
}

.cta-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

/* ========================================
   服务详情页
   ======================================== */

.service-detail {
    background: var(--bg-white);
    border-radius: var(--radius-xl);
    padding: 48px;
    margin-bottom: 32px;
    box-shadow: var(--shadow);
}

.service-tagline {
    font-size: 18px;
    color: var(--primary);
    font-weight: 600;
    margin-bottom: 16px;
}

.service-detail h3 {
    font-size: 28px;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 24px;
}

.service-detail p {
    font-size: 16px;
    color: var(--text-gray);
    line-height: 1.8;
    margin-bottom: 24px;
}

.service-scenarios {
    background: var(--bg-light);
    border-radius: var(--radius-lg);
    padding: 24px 32px;
}

.service-scenarios h4 {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 16px;
}

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

.service-scenarios li {
    padding: 8px 0;
    padding-left: 24px;
    position: relative;
    color: var(--text-gray);
}

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

/* ========================================
   行业解决方案
   ======================================== */

.industry-card {
    background: var(--bg-white);
    border-radius: var(--radius-xl);
    padding: 40px;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
}

.industry-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.industry-icon {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 24px;
    color: white;
    font-size: 28px;
}

.industry-card h3 {
    font-size: 22px;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 16px;
}

.industry-card p {
    font-size: 16px;
    color: var(--text-gray);
    line-height: 1.7;
}

/* ========================================
   联系表单
   ======================================== */

.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
}

.contact-form-wrapper {
    background: var(--bg-white);
    border-radius: var(--radius-xl);
    padding: 40px;
    box-shadow: var(--shadow);
}

.contact-form h3 {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 24px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 8px;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    font-size: 15px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    transition: all 0.2s ease;
    font-family: inherit;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(30, 58, 138, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

.contact-info {
    padding: 40px 0;
}

.contact-info h3 {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 16px;
}

.contact-info p {
    font-size: 16px;
    color: var(--text-gray);
    line-height: 1.7;
    margin-bottom: 32px;
}

.contact-detail {
    display: flex;
    gap: 16px;
    margin-bottom: 24px;
}

.contact-detail-icon {
    width: 48px;
    height: 48px;
    background: var(--bg-light);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    font-size: 20px;
}

.contact-detail-text h4 {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: 4px;
}

.contact-detail-text p {
    font-size: 15px;
    color: var(--text-gray);
    margin: 0;
}

/* ========================================
   页脚
   ======================================== */

.footer {
    background: var(--primary-dark);
    color: white;
    padding: 64px 0 24px;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 48px;
    margin-bottom: 48px;
}

.footer-brand {
    max-width: 360px;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
}

.footer-logo-img {
    height: 36px;
    width: auto;
    filter: brightness(0) invert(1);
}

.footer-tagline {
    font-size: 15px;
    opacity: 0.8;
    line-height: 1.7;
}

.footer-column h4 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 20px;
}

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

.footer-links li {
    margin-bottom: 12px;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    font-size: 14px;
    transition: color 0.2s ease;
}

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

.footer-bottom {
    padding-top: 24px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
}

.footer-copyright {
    font-size: 14px;
    opacity: 0.7;
}

/* ========================================
   响应式
   ======================================== */

@media (max-width: 1024px) {
    .card-grid-4 {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .advantage-list {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .footer-content {
        grid-template-columns: 1fr 1fr;
    }
    
    .contact-wrapper {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .nav {
        display: none;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .hero {
        padding: 80px 0;
    }
    
    .hero-title {
        font-size: 32px;
    }
    
    .hero-subtitle {
        font-size: 16px;
    }
    
    .section {
        padding: 64px 0;
    }
    
    .section-title {
        font-size: 28px;
    }
    
    .card-grid {
        grid-template-columns: 1fr;
    }
    
    .card-grid-2 {
        grid-template-columns: 1fr;
    }
    
    .card-grid-4 {
        grid-template-columns: 1fr;
    }
    
    .advantage-list {
        grid-template-columns: 1fr;
    }
    
    .cta-title {
        font-size: 24px;
    }
    
    .service-detail {
        padding: 32px 24px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 32px;
    }
}