/* ============================================
   VittelTech 官网样式表
   ============================================ */

/* ============================================
   CSS变量定义
   ============================================ */
:root {
    /* 主色调 */
    --primary-color: #1E3A8A;
    --primary-light: #3B82F6;
    --primary-dark: #1E40AF;

    /* 辅助色 */
    --accent-color: #F59E0B;
    --accent-light: #FBBF24;

    /* 中性色 */
    --text-primary: #1F2937;
    --text-secondary: #4B5563;
    --text-muted: #9CA3AF;
    --text-light: #F9FAFB;

    /* 背景色 */
    --bg-white: #FFFFFF;
    --bg-light: #F8FAFC;
    --bg-gray: #F3F4F6;
    --bg-dark: #111827;

    /* 边框色 */
    --border-color: #E5E7EB;
    --border-light: #F3F4F6;

    /* 阴影 */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 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);

    /* 过渡 */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;

    /* 圆角 */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-full: 9999px;

    /* 间距 */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;

    /* 容器宽度 */
    --container-max: 1280px;
    --container-narrow: 960px;

    /* 导航栏高度 */
    --header-height: 60px;
    --header-height-scrolled: 50px;

    /* 字体 */
    --font-primary: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-heading: 'Inter', 'Noto Sans SC', sans-serif;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
    scroll-padding-top: 80px;
}

/* 锚点跳转时避免被固定导航栏遮挡 */
[id] {
    scroll-margin-top: 80px;
}

body {
    font-family: var(--font-primary);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* 图片懒加载样式 */
img[data-src] {
    opacity: 0;
    transition: opacity 0.3s ease;
}

img.loaded {
    opacity: 1;
}

/* 图片加载占位 */
.img-placeholder {
    background: var(--bg-gray);
    position: relative;
    overflow: hidden;
}

.img-placeholder::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.5), transparent);
    animation: shimmer 1.5s infinite;
}

@keyframes shimmer {
    100% {
        left: 100%;
    }
}

a {
    color: inherit;
    text-decoration: none;
    transition: color var(--transition-fast);
}

ul, ol {
    list-style: none;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

input, textarea, select {
    font-family: inherit;
    font-size: inherit;
}

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

/* ============================================
   导航栏
   ============================================ */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    z-index: 1000;
    transition: all var(--transition-normal);
}

.header.scrolled {
    height: var(--header-height-scrolled);
    box-shadow: var(--shadow-md);
}

.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex-shrink: 0;
}

.logo-img {
    max-width: 120px;
    height: 50px;
    width: auto;
}

.logo-text {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    letter-spacing: -0.02em;
}

/* 导航菜单 */
.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.nav-item {
    position: relative;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--text-secondary);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

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

.nav-link i {
    font-size: 0.75rem;
    transition: transform var(--transition-fast);
}

.nav-item:hover .nav-link i {
    transform: rotate(180deg);
}

/* 下拉菜单 */
.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 180px;
    padding: var(--spacing-sm) 0;
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: all var(--transition-fast);
}

.nav-item:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-menu li a {
    display: block;
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: 0.875rem;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.dropdown-menu li a:hover {
    color: var(--primary-color);
    background: var(--bg-light);
    padding-left: var(--spacing-xl);
}

/* 导航操作区 */
.nav-actions {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.search-toggle {
    width: 44px;  /* 增加宽度 */
    height: 44px; /* 增加高度 */
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
    order: 2; /* 搜索按钮在导航操作区内排第二（汉堡按钮后） */
}

.search-toggle i {
    font-size: 1.25rem; /* 增大搜索图标 */
}

.search-toggle:hover {
    color: var(--primary-color);
    background: var(--bg-light);
}

.lang-switch {
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

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

/* 汉堡菜单按钮 - 移动端显示 */
.nav-toggle {
    display: none;
    width: 40px;
    height: 40px;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 6px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 1001;
    order: 1; /* 汉堡按钮在导航操作区内排第一（搜索按钮前） */
}

.hamburger,
.hamburger::before,
.hamburger::after {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: all var(--transition-fast);
}

.hamburger {
    position: relative;
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    left: 0;
}

.hamburger::before {
    top: -7px;
}

.hamburger::after {
    top: 7px;
}

.nav-toggle.active .hamburger {
    background: transparent;
}

.nav-toggle.active .hamburger::before {
    top: 0;
    transform: rotate(45deg);
}

.nav-toggle.active .hamburger::after {
    top: 0;
    transform: rotate(-45deg);
}

/* 搜索覆盖层 */
.search-overlay {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    padding: var(--spacing-lg);
    background: var(--bg-white);
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all var(--transition-fast);
}

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

.search-form {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    max-width: 600px;
    margin: 0 auto;
}

.search-input {
    flex: 1;
    padding: var(--spacing-md) var(--spacing-lg);
    font-size: 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-full);
    outline: none;
    transition: border-color var(--transition-fast);
}

.search-input:focus {
    border-color: var(--primary-color);
}

.search-btn,
.search-close {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
}

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

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

.search-close {
    color: var(--text-secondary);
}

.search-close:hover {
    background: var(--bg-light);
}

/* ============================================
   主Banner轮播
   ============================================ */
.hero-slider {
    position: relative;
    height: 100vh;
    min-height: 600px;
    max-height: 900px;
    overflow: hidden;
}

.slider-wrapper {
    height: 100%;
}

.slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.8s ease, visibility 0.8s ease;
}

.slide.active {
    opacity: 1;
    visibility: visible;
}

.slide-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(30, 58, 138, 0.85) 0%, rgba(30, 58, 138, 0.6) 50%, rgba(30, 58, 138, 0.4) 100%);
}

.slide-content {
    position: relative;
    z-index: 1;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    padding-top: calc(var(--header-height) + 8vh);
    color: var(--text-light);
}

.slide-title {
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    letter-spacing: -0.02em;
}

.slide-subtitle {
    font-size: 1.25rem;
    font-weight: 400;
    opacity: 0.9;
    margin-bottom: var(--spacing-lg);
    letter-spacing: 0.05em;
}

.slide-desc {
    font-size: 1.125rem;
    opacity: 0.85;
    margin-bottom: var(--spacing-xl);
    max-width: 500px;
}

.slide-btns {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

/* 轮播动画 */
.animate-fade-up {
    opacity: 0;
    transform: translateY(30px);
    animation: fadeUp 0.8s ease forwards;
}

.delay-1 { animation-delay: 0.2s; }
.delay-2 { animation-delay: 0.4s; }
.delay-3 { animation-delay: 0.6s; }

@keyframes fadeUp {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 轮播控制 */
.slider-controls {
    position: absolute;
    bottom: var(--spacing-2xl);
    left: 0;
    right: 0;
    z-index: 10;
}

.slider-dots {
    display: flex;
    gap: var(--spacing-sm);
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: var(--radius-full);
    background: rgba(255, 255, 255, 0.4);
    transition: all var(--transition-fast);
}

.dot:hover {
    background: rgba(255, 255, 255, 0.7);
}

.dot.active {
    width: 36px;
    background: var(--accent-color);
}

/* 滚动提示 */
.scroll-indicator {
    position: absolute;
    bottom: var(--spacing-3xl);
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--text-light);
    font-size: 0.875rem;
    opacity: 0.7;
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% { transform: translateX(-50%) translateY(0); }
    40% { transform: translateX(-50%) translateY(-10px); }
    60% { transform: translateX(-50%) translateY(-5px); }
}

/* ============================================
   按钮样式
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 0.9375rem;
    font-weight: 500;
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
    cursor: pointer;
    white-space: nowrap;
}

.btn-sm {
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 0.875rem;
}

.btn-lg {
    padding: var(--spacing-lg) var(--spacing-2xl);
    font-size: 1rem;
}

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

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

.btn-outline {
    background: transparent;
    color: var(--text-light);
    border: 2px solid rgba(255, 255, 255, 0.5);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.8);
}

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

.btn-white:hover {
    background: var(--bg-light);
    border-color: var(--bg-light);
}

/* ============================================
   Section通用样式
   ============================================ */
.section {
    padding: var(--spacing-3xl) 0;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-3xl);
}

.section-title {
    font-size: 2.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
    letter-spacing: -0.02em;
}

.section-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

.section-footer {
    text-align: center;
    margin-top: var(--spacing-3xl);
}

/* ============================================
   核心业务区
   ============================================ */
.core-business {
    background: var(--bg-light);
}

.business-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xl);
}

.business-card {
    background: var(--bg-white);
    padding: var(--spacing-2xl);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
}

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

.card-icon {
    width: 64px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-lg);
}

.card-icon i {
    font-size: 1.75rem;
    color: var(--text-light);
}

.card-title {
    font-size: 1.375rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-md);
}

.card-desc {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: var(--spacing-lg);
}

.card-features {
    margin-bottom: var(--spacing-lg);
}

.card-features li {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-xs) 0;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.card-features li i {
    color: var(--accent-color);
    font-size: 0.75rem;
}

.card-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--primary-color);
    transition: all var(--transition-fast);
}

.card-link:hover {
    gap: var(--spacing-md);
    color: var(--primary-dark);
}

/* ============================================
   热门产品展示
   ============================================ */
.products-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-lg);
}

.product-card {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
    border: 1px solid var(--border-light);
}

.product-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-light);
}

.product-image {
    position: relative;
    aspect-ratio: 1;
    overflow: hidden;
    background: var(--bg-gray);
}

.product-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

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

.product-overlay {
    position: absolute;
    inset: 0;
    background: rgba(30, 58, 138, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.product-card:hover .product-overlay {
    opacity: 1;
}

.product-info {
    padding: var(--spacing-lg);
}

.product-category {
    display: inline-block;
    padding: 2px 10px;
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--primary-color);
    background: rgba(30, 58, 138, 0.1);
    border-radius: var(--radius-full);
    margin-bottom: var(--spacing-sm);
}

.product-name {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
}

.product-model {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-md);
    font-family: monospace;
}

.product-specs {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.product-specs li {
    font-size: 0.8125rem;
    color: var(--text-secondary);
}

.product-specs li span {
    color: var(--text-muted);
}

/* ============================================
   数据统计区
   ============================================ */
.stats-section {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: var(--text-light);
    padding: var(--spacing-3xl) 0;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-xl);
    text-align: center;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.stat-number {
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1;
}

.stat-suffix {
    font-size: 2rem;
    font-weight: 700;
    color: var(--accent-color);
}

.stat-label {
    font-size: 1rem;
    opacity: 0.9;
    margin-top: var(--spacing-sm);
}

/* ============================================
   应用场景
   ============================================ */
.solutions-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-lg);
}

.solution-card {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
}

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

.solution-image {
    position: relative;
    height: 180px;
    overflow: hidden;
}

.solution-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

.solution-card:hover .solution-image img {
    transform: scale(1.1);
}

.solution-content {
    padding: var(--spacing-lg);
    position: relative;
}

.solution-icon {
    position: absolute;
    top: -24px;
    left: var(--spacing-lg);
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-color);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
}

.solution-icon i {
    font-size: 1.25rem;
    color: var(--text-light);
}

.solution-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-top: var(--spacing-lg);
    margin-bottom: var(--spacing-sm);
}

.solution-desc {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: var(--spacing-md);
}

.solution-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--primary-color);
    transition: all var(--transition-fast);
}

.solution-link:hover {
    gap: var(--spacing-md);
}

/* ============================================
   为什么选择我们
   ============================================ */
.why-us-section {
    background: var(--bg-light);
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xl);
}

.advantage-item {
    background: var(--bg-white);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    text-align: center;
    transition: all var(--transition-normal);
}

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

.advantage-icon {
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary-light), var(--primary-color));
    border-radius: var(--radius-full);
    margin: 0 auto var(--spacing-lg);
}

.advantage-icon i {
    font-size: 1.5rem;
    color: var(--text-light);
}

.advantage-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
}

.advantage-desc {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ============================================
   新闻动态
   ============================================ */
.news-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
}

.news-card {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
}

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

.news-image {
    position: relative;
    height: 200px;
    overflow: hidden;
}

.news-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

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

.news-tag {
    position: absolute;
    top: var(--spacing-md);
    left: var(--spacing-md);
    padding: 4px 12px;
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--text-light);
    background: var(--primary-color);
    border-radius: var(--radius-full);
}

.news-content {
    padding: var(--spacing-lg);
}

.news-date {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 0.8125rem;
    color: var(--text-muted);
    margin-bottom: var(--spacing-sm);
}

.news-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.4;
    margin-bottom: var(--spacing-sm);
}

.news-excerpt {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: var(--spacing-md);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.news-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--primary-color);
    transition: all var(--transition-fast);
}

.news-link:hover {
    gap: var(--spacing-md);
}

/* ============================================
   合作伙伴
   ============================================ */
.partners-section {
    background: var(--bg-light);
    padding: var(--spacing-2xl) 0;
}

.partners-slider {
    overflow: hidden;
}

.partners-track {
    display: flex;
    gap: var(--spacing-2xl);
    animation: scroll 20s linear infinite;
}

.partner-logo {
    flex-shrink: 0;
    width: 120px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-white);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    filter: grayscale(100%);
    opacity: 0.7;
    transition: all var(--transition-fast);
}

.partner-logo:hover {
    filter: grayscale(0);
    opacity: 1;
}

.partner-logo img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

@keyframes scroll {
    0% { transform: translateX(0); }
    100% { transform: translateX(-50%); }
}

/* ============================================
   页脚
   ============================================ */
.footer {
    background: var(--bg-dark);
    color: var(--text-light);
}

.footer-top {
    padding: var(--spacing-3xl) 0;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1fr 1.2fr;
    gap: var(--spacing-xl);
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-lg);
}

.footer-logo img {
    height: 36px;
}

.footer-logo span {
    font-size: 1.25rem;
    font-weight: 700;
}

.footer-desc {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.7;
    margin-bottom: var(--spacing-lg);
}

.footer-social {
    display: flex;
    gap: var(--spacing-sm);
}

.social-link {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-full);
    color: var(--text-light);
    transition: all var(--transition-fast);
}

.social-link:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
}

.footer-title {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
}

.footer-links li {
    margin-bottom: var(--spacing-sm);
}

.footer-links a {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.7);
    transition: all var(--transition-fast);
}

.footer-links a:hover {
    color: var(--text-light);
    padding-left: var(--spacing-sm);
}

.contact-list li {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.7);
}

.contact-list li i {
    margin-top: 4px;
    color: var(--primary-light);
}

.contact-list a {
    color: rgba(255, 255, 255, 0.7);
}

.contact-list a:hover {
    color: var(--text-light);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding: var(--spacing-lg) 0;
}

.footer-bottom-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.copyright,
.icp {
    font-size: 0.8125rem;
    color: rgba(255, 255, 255, 0.5);
}

.footer-bottom-links {
    display: flex;
    gap: var(--spacing-lg);
}

.footer-bottom-links a {
    font-size: 0.8125rem;
    color: rgba(255, 255, 255, 0.5);
    transition: color var(--transition-fast);
}

.footer-bottom-links a:hover {
    color: var(--text-light);
}

/* ============================================
   返回顶部按钮
   ============================================ */
.back-to-top {
    position: fixed;
    right: var(--spacing-xl);
    bottom: var(--spacing-xl);
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-color);
    color: var(--text-light);
    border-radius: var(--radius-full);
    box-shadow: var(--shadow-lg);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all var(--transition-fast);
    z-index: 999;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-3px);
}

.back-to-top i {
    font-size: 1.25rem;
}

/* ============================================
   动画效果
   ============================================ */
[data-aos="fade-up"] {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

[data-aos="fade-up"].aos-animate {
    opacity: 1;
    transform: translateY(0);
}

[data-aos="zoom-in"] {
    opacity: 0;
    transform: scale(0.9);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

[data-aos="zoom-in"].aos-animate {
    opacity: 1;
    transform: scale(1);
}

/* 动画延迟 */
[data-aos-delay="50"] { transition-delay: 50ms; }
[data-aos-delay="100"] { transition-delay: 100ms; }
[data-aos-delay="150"] { transition-delay: 150ms; }
[data-aos-delay="200"] { transition-delay: 200ms; }
[data-aos-delay="250"] { transition-delay: 250ms; }
[data-aos-delay="300"] { transition-delay: 300ms; }