/**
 * QianTu Ark - 前台样式
 * 基于Tailwind思想的自定义CSS
 */

/* ==================== 基础重置 ==================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #3b82f6;
    --primary-dark: #2563eb;
    --secondary-color: #64748b;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-900: #111827;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--gray-900);
    background: #fff;
}

/* ==================== 容器 ==================== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* ==================== 头部导航 ==================== */
.header {
    background: #fff;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 1rem;
}

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

.logo-text {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--gray-900);
    text-decoration: none;
}

.nav-desktop {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    color: var(--gray-700);
    text-decoration: none;
    transition: color 0.3s;
    font-weight: 500;
}

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

/* 语言切换器 */
.lang-switcher {
    position: relative;
}

.lang-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    border: 1px solid var(--gray-300);
    border-radius: 0.5rem;
    background: #fff;
    cursor: pointer;
    transition: all 0.3s;
}

.lang-btn:hover {
    border-color: var(--primary-color);
}

.lang-dropdown {
    position: absolute;
    top: 100%;
    right: 0;
    margin-top: 0.5rem;
    background: #fff;
    border: 1px solid var(--gray-200);
    border-radius: 0.5rem;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    min-width: 120px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.3s;
}

.lang-dropdown.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.lang-option {
    display: block;
    width: 100%;
    padding: 0.75rem 1rem;
    border: none;
    background: none;
    text-align: left;
    cursor: pointer;
    transition: background 0.3s;
}

.lang-option:hover {
    background: var(--gray-100);
}

.lang-option.active {
    color: var(--primary-color);
    background: var(--gray-50);
}

/* 移动菜单按钮 */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 4px;
    padding: 0.5rem;
    border: none;
    background: none;
    cursor: pointer;
}

.mobile-menu-btn span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--gray-900);
    transition: all 0.3s;
}

.mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* 移动菜单 */
.mobile-menu {
    display: none;
    background: #fff;
    border-top: 1px solid var(--gray-200);
}

.mobile-menu.show {
    display: block;
}

.mobile-nav {
    padding: 1rem 0;
}

.mobile-nav-link {
    display: block;
    padding: 0.75rem 1.5rem;
    color: var(--gray-700);
    text-decoration: none;
    transition: all 0.3s;
}

.mobile-nav-link:hover {
    background: var(--gray-50);
    color: var(--primary-color);
}

.mobile-lang {
    display: flex;
    gap: 0.5rem;
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--gray-200);
}

.mobile-lang-option {
    flex: 1;
    padding: 0.5rem;
    border: 1px solid var(--gray-300);
    border-radius: 0.375rem;
    background: #fff;
    cursor: pointer;
    transition: all 0.3s;
}

.mobile-lang-option:hover {
    border-color: var(--primary-color);
}

.mobile-lang-option.active {
    background: var(--primary-color);
    color: #fff;
    border-color: var(--primary-color);
}

/* ==================== 主内容 ==================== */
.main-content {
    margin-top: 70px;
    min-height: calc(100vh - 70px);
}

/* Hero区域 */
.hero {
    position: relative;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    overflow: hidden;
}

/* Hero视频背景 */
.hero-video {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    min-width: 100%;
    min-height: 100%;
    width: auto;
    height: auto;
    max-width: none;
    object-fit: cover;
    z-index: 0;
}

/* Hero背景图片 */
.hero-bg {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    min-width: 100%;
    min-height: 100%;
    width: auto;
    height: auto;
    max-width: none;
    object-fit: cover;
    z-index: 0;
}

/* Hero遮罩层 */
.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1;
}

.hero .container {
    position: relative;
    z-index: 2;
}

.hero-content {
    max-width: 900px;
    margin: 0 auto;
    background: rgba(0, 0, 0, 0.3);
    padding: 3rem 2rem;
    border-radius: 1.5rem;
    backdrop-filter: blur(10px);
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 2.5rem;
    opacity: 0.95;
    text-shadow: 1px 1px 2px rgba(0,0,0,0.3);
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

/* 按钮 */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: 0.5rem;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
}

.btn-secondary {
    background: #fff;
    color: var(--primary-color);
}

.btn-secondary:hover {
    background: var(--gray-100);
}

/* 分类展示 */
.categories {
    padding: 4rem 0;
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
}

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

.category-card {
    background: #fff;
    padding: 2rem;
    border-radius: 1rem;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    text-align: center;
    transition: all 0.3s;
}

.category-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 15px rgba(0,0,0,0.15);
}

.category-icon {
    width: 60px;
    height: 60px;
    margin: 0 auto 1rem;
    color: var(--primary-color);
}

.category-name {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.category-description {
    color: var(--gray-600);
    margin-bottom: 1.5rem;
}

.category-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

/* 特性展示 */
.features {
    padding: 4rem 0;
    background: var(--gray-50);
}

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

.feature-card {
    background: #fff;
    padding: 2rem;
    border-radius: 0.5rem;
    text-align: center;
}

.feature-icon {
    width: 50px;
    height: 50px;
    margin: 0 auto 1rem;
    color: var(--primary-color);
}

/* 产品页面 */
.breadcrumb {
    padding: 2rem 0 1rem;
    color: var(--gray-600);
}

.breadcrumb a {
    color: var(--primary-color);
    text-decoration: none;
}

.breadcrumb-separator {
    margin: 0 0.5rem;
}

.page-header {
    text-align: center;
    margin-bottom: 3rem;
}

.page-header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
}

.page-header p {
    color: var(--gray-600);
    font-size: 1.125rem;
}

.product-category {
    margin-bottom: 4rem;
}

.category-header {
    margin-bottom: 2rem;
}

.category-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.category-desc {
    color: var(--gray-600);
    font-size: 1.125rem;
}

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

.product-card {
    background: #fff;
    border-radius: 1rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    overflow: hidden;
    transition: all 0.3s;
}

.product-card:hover {
    box-shadow: 0 8px 15px rgba(0,0,0,0.15);
}

.product-image {
    position: relative;
    height: 250px;
    overflow: hidden;
}

.product-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s;
}

.product-card:hover .product-image img {
    transform: scale(1.05);
}

.product-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(0,0,0,0.6), transparent);
}

.product-name {
    position: absolute;
    bottom: 1rem;
    left: 1rem;
    right: 1rem;
    color: #fff;
    font-size: 1.25rem;
    font-weight: 600;
}

.product-content {
    padding: 1.5rem;
}

.product-description {
    color: var(--gray-600);
    margin-bottom: 1rem;
}

.product-inquiry {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

/* 关于我们页面 */
.about-section {
    margin-bottom: 4rem;
}

.about-section h2 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 2rem;
}

.about-content p {
    margin-bottom: 1rem;
    line-height: 1.8;
    color: var(--gray-700);
}

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

.advantage-card {
    padding: 2rem;
    border-radius: 0.5rem;
    background: var(--gray-50);
}

.advantage-number {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

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

.business-card {
    padding: 2rem;
    background: #fff;
    border: 1px solid var(--gray-200);
    border-radius: 0.5rem;
}

.business-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

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

.business-card li {
    padding: 0.5rem 0;
    padding-left: 1.5rem;
    position: relative;
}

.business-card li:before {
    content: "•";
    position: absolute;
    left: 0;
    color: var(--primary-color);
}

.about-cta {
    text-align: center;
    padding: 4rem 2rem;
    background: var(--gray-50);
    border-radius: 1rem;
}

.about-cta h2 {
    margin-bottom: 1rem;
}

.cta-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-top: 2rem;
}

/* ==================== 底部 ==================== */
.footer {
    background: var(--gray-900);
    color: #fff;
    padding: 3rem 0 1rem;
}

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

.footer-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.footer-desc {
    color: var(--gray-300);
    line-height: 1.6;
}

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

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

.footer-links a {
    color: var(--gray-300);
    text-decoration: none;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: #fff;
}

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

.footer-contact li {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.75rem;
}

.footer-contact a {
    color: var(--gray-300);
    text-decoration: none;
}

.footer-contact a:hover {
    color: #fff;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid var(--gray-700);
    color: var(--gray-400);
}

/* ==================== 图标 ==================== */
.icon {
    width: 100%;
    height: 100%;
}

.icon-small {
    width: 20px;
    height: 20px;
}

.icon-tiny {
    width: 16px;
    height: 16px;
}

.icon-tiny.rotate {
    transform: rotate(180deg);
}

/* ==================== About Us Home Section ==================== */
.about-home {
    padding: 4rem 0;
    background: #f9fafb;
}

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

.about-content {
    /* 左侧内容 */
}

.about-subtitle {
    font-size: 1.5rem;
    font-weight: 600;
}

.about-text {
    font-size: 1rem;
}

.about-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

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

.about-feature-icon {
    flex-shrink: 0;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #eff6ff;
    border-radius: 0.5rem;
}

.about-feature-item h4 {
    margin: 0 0 0.25rem 0;
    font-size: 1rem;
    font-weight: 600;
}

.about-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.stat-card {
    padding: 2rem;
    border-radius: 1rem;
    text-align: center;
}

.stat-value {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 1rem;
    font-weight: 500;
}

/* ==================== 响应式 ==================== */
@media (max-width: 768px) {
    .nav-desktop {
        display: none;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
    }
    
    .logo-text {
        display: none;
    }
    
    .category-grid,
    .products-grid,
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .cta-buttons {
        flex-direction: column;
    }
    
    /* About Us 响应式 */
    .about-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .about-features {
        grid-template-columns: 1fr;
    }
    
    .about-stats {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 1.75rem;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .stat-value {
        font-size: 2rem;
    }
}