/* ============================================
   殴易官网 - 全局样式表
   专业数字资产交易平台风格
   ============================================ */

/* ===== CSS变量定义 ===== */
:root {
    --primary-color: #1a56db;
    --primary-dark: #0e42c6;
    --primary-light: #3b82f6;
    --secondary-color: #06b6d4;
    --accent-color: #f59e0b;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --text-dark: #1e293b;
    --text-gray: #64748b;
    --text-light: #94a3b8;
    --bg-light: #f8fafc;
    --bg-white: #ffffff;
    --bg-dark: #0f172a;
    --bg-gradient: linear-gradient(135deg, #0f172a 0%, #1e3a5f 50%, #1a56db 100%);
    --card-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --card-shadow-hover: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --transition: all 0.3s ease;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --max-width: 1200px;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-white);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

a:hover {
    color: var(--primary-dark);
}

ul, ol {
    list-style: none;
}

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

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

/* ===== 导航栏 ===== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.08);
    transition: var(--transition);
}

.header.scrolled {
    box-shadow: 0 2px 30px rgba(0, 0, 0, 0.15);
}

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

.nav-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-dark);
}

.nav-brand img {
    width: 40px;
    height: 40px;
    border-radius: 10px;
}

.nav-brand span {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-menu a {
    font-weight: 500;
    color: var(--text-dark);
    position: relative;
    padding: 8px 0;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    transition: var(--transition);
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--primary-color);
}

.nav-menu a:hover::after,
.nav-menu a.active::after {
    width: 100%;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 16px;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    font-size: 0.95rem;
    font-weight: 600;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    white-space: nowrap;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    color: #fff;
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
    color: #fff;
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(26, 86, 219, 0.3);
}

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

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

.btn-lg {
    padding: 16px 36px;
    font-size: 1.05rem;
}

.btn-mobile-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 8px;
}

.btn-mobile-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-dark);
    border-radius: 2px;
    transition: var(--transition);
}

/* ===== Hero区域 ===== */
.hero {
    min-height: 100vh;
    background: var(--bg-gradient);
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    padding-top: 72px;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 800px;
    height: 800px;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.3) 0%, transparent 70%);
    border-radius: 50%;
    animation: float 20s ease-in-out infinite;
}

.hero::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -10%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(6, 182, 212, 0.2) 0%, transparent 70%);
    border-radius: 50%;
    animation: float 25s ease-in-out infinite reverse;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(30px, -30px); }
}

.hero-content {
    position: relative;
    z-index: 2;
    color: #fff;
    max-width: 700px;
}

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 24px;
    animation: fadeInUp 1s ease;
}

.hero-content h1 .highlight {
    background: linear-gradient(135deg, #60a5fa, #22d3ee);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-content p {
    font-size: 1.2rem;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 40px;
    animation: fadeInUp 1s ease 0.2s both;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    animation: fadeInUp 1s ease 0.4s both;
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 30px;
    margin-top: 60px;
    animation: fadeInUp 1s ease 0.6s both;
}

.stat-item {
    text-align: left;
}

.stat-number {
    font-size: 2.25rem;
    font-weight: 800;
    background: linear-gradient(135deg, #60a5fa, #22d3ee);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.7);
    margin-top: 4px;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ===== 通用Section ===== */
.section {
    padding: 100px 0;
}

.section-title {
    text-align: center;
    margin-bottom: 60px;
}

.section-title h2 {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 16px;
}

.section-title p {
    font-size: 1.1rem;
    color: var(--text-gray);
    max-width: 600px;
    margin: 0 auto;
}

.section-title .title-bar {
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
    margin: 16px auto 0;
}

/* ===== 核心特性 ===== */
.features {
    background: var(--bg-light);
}

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

.feature-card {
    background: var(--bg-white);
    border-radius: var(--radius-md);
    padding: 40px 32px;
    box-shadow: var(--card-shadow);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    transform: scaleX(0);
    transition: var(--transition);
    transform-origin: left;
}

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

.feature-card:hover::before {
    transform: scaleX(1);
}

.feature-icon {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, rgba(26, 86, 219, 0.1), rgba(6, 182, 212, 0.1));
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    margin-bottom: 24px;
}

.feature-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 12px;
}

.feature-card p {
    color: var(--text-gray);
    font-size: 0.95rem;
    line-height: 1.7;
}

/* ===== 服务介绍 ===== */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
}

.service-card {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--card-shadow);
    transition: var(--transition);
    border: 1px solid rgba(0, 0, 0, 0.05);
}

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

.service-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.service-body {
    padding: 28px;
}

.service-tag {
    display: inline-block;
    padding: 4px 12px;
    background: linear-gradient(135deg, rgba(26, 86, 219, 0.1), rgba(6, 182, 212, 0.1));
    color: var(--primary-color);
    font-size: 0.8rem;
    font-weight: 600;
    border-radius: 20px;
    margin-bottom: 12px;
}

.service-card h3 {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 10px;
}

.service-card p {
    color: var(--text-gray);
    font-size: 0.9rem;
    line-height: 1.6;
}

.service-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-top: 16px;
    font-weight: 600;
    font-size: 0.9rem;
}

/* ===== 详细内容区 ===== */
.about-section {
    background: var(--bg-white);
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.about-image {
    position: relative;
}

.about-image img {
    border-radius: var(--radius-lg);
    box-shadow: var(--card-shadow-hover);
}

.about-image::after {
    content: '';
    position: absolute;
    bottom: -20px;
    right: -20px;
    width: 60%;
    height: 60%;
    background: linear-gradient(135deg, rgba(26, 86, 219, 0.2), rgba(6, 182, 212, 0.2));
    border-radius: var(--radius-lg);
    z-index: -1;
}

.about-content h2 {
    font-size: 2.25rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 24px;
}

.about-content p {
    color: var(--text-gray);
    font-size: 1rem;
    line-height: 1.8;
    margin-bottom: 20px;
}

.about-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-top: 32px;
}

.about-feature-item {
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 500;
    color: var(--text-dark);
}

.about-feature-item::before {
    content: '✓';
    width: 24px;
    height: 24px;
    background: var(--success-color);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    font-weight: 700;
}

/* ===== 数据统计 ===== */
.stats-section {
    background: var(--bg-gradient);
    color: #fff;
    padding: 80px 0;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    text-align: center;
}

.stats-item h3 {
    font-size: 3rem;
    font-weight: 800;
    background: linear-gradient(135deg, #60a5fa, #22d3ee);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 8px;
}

.stats-item p {
    font-size: 1rem;
    color: rgba(255, 255, 255, 0.8);
}

/* ===== CTA区域 ===== */
.cta {
    background: linear-gradient(135deg, #0f172a 0%, #1e3a5f 100%);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.cta::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(26, 86, 219, 0.3) 0%, transparent 70%);
    border-radius: 50%;
}

.cta-content {
    position: relative;
    z-index: 2;
}

.cta h2 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #fff;
    margin-bottom: 20px;
}

.cta p {
    font-size: 1.2rem;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 40px;
}

.cta .btn-primary {
    background: linear-gradient(135deg, var(--secondary-color), var(--primary-light));
}

/* ===== 常见问题FAQ ===== */
.faq {
    background: var(--bg-light);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: var(--bg-white);
    border-radius: var(--radius-md);
    margin-bottom: 16px;
    box-shadow: var(--card-shadow);
    overflow: hidden;
}

.faq-question {
    width: 100%;
    padding: 24px 28px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--text-dark);
    text-align: left;
    transition: var(--transition);
}

.faq-question:hover {
    color: var(--primary-color);
}

.faq-question .icon {
    width: 24px;
    height: 24px;
    position: relative;
    flex-shrink: 0;
    margin-left: 16px;
}

.faq-question .icon::before,
.faq-question .icon::after {
    content: '';
    position: absolute;
    background: currentColor;
    border-radius: 2px;
    transition: var(--transition);
}

.faq-question .icon::before {
    top: 50%;
    left: 50%;
    width: 16px;
    height: 2px;
    transform: translate(-50%, -50%);
}

.faq-question .icon::after {
    top: 50%;
    left: 50%;
    width: 2px;
    height: 16px;
    transform: translate(-50%, -50%);
}

.faq-item.active .faq-question .icon::after {
    opacity: 0;
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-answer-content {
    padding: 0 28px 24px;
    color: var(--text-gray);
    line-height: 1.8;
}

/* ===== 新闻列表页 ===== */
.news-list {
    padding: 120px 0 80px;
    background: var(--bg-light);
}

.news-list-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 30px;
}

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

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

.news-card-image {
    position: relative;
    height: 220px;
    overflow: hidden;
}

.news-card-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

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

.news-card-category {
    position: absolute;
    top: 16px;
    left: 16px;
    padding: 6px 14px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: #fff;
    font-size: 0.8rem;
    font-weight: 600;
    border-radius: 20px;
}

.news-card-body {
    padding: 28px;
}

.news-card-date {
    font-size: 0.85rem;
    color: var(--text-light);
    margin-bottom: 12px;
}

.news-card h3 {
    font-size: 1.15rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 12px;
    line-height: 1.5;
    transition: var(--transition);
}

.news-card:hover h3 {
    color: var(--primary-color);
}

.news-card p {
    color: var(--text-gray);
    font-size: 0.9rem;
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* ===== 新闻详情页 ===== */
.news-detail {
    padding: 120px 0 80px;
}

.news-detail-wrapper {
    max-width: 900px;
    margin: 0 auto;
}

.news-detail-header {
    margin-bottom: 40px;
}

.news-detail-category {
    display: inline-block;
    padding: 6px 16px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: #fff;
    font-size: 0.85rem;
    font-weight: 600;
    border-radius: 20px;
    margin-bottom: 20px;
}

.news-detail-header h1 {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text-dark);
    line-height: 1.3;
    margin-bottom: 20px;
}

.news-detail-meta {
    display: flex;
    gap: 24px;
    color: var(--text-gray);
    font-size: 0.9rem;
}

.news-detail-content {
    background: var(--bg-white);
    padding: 48px;
    border-radius: var(--radius-lg);
    box-shadow: var(--card-shadow);
}

.news-detail-content p {
    font-size: 1.05rem;
    line-height: 1.9;
    color: var(--text-dark);
    margin-bottom: 24px;
}

.news-detail-content h2 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-dark);
    margin: 40px 0 20px;
}

.news-detail-content img {
    border-radius: var(--radius-md);
    margin: 32px 0;
}

/* ===== 联系页 ===== */
.contact-section {
    padding: 120px 0 80px;
    background: var(--bg-light);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    max-width: 1100px;
    margin: 0 auto;
}

.contact-info h2 {
    font-size: 2.25rem;
    font-weight: 700;
    margin-bottom: 20px;
}

.contact-info p {
    color: var(--text-gray);
    margin-bottom: 40px;
    line-height: 1.8;
}

.contact-item {
    display: flex;
    gap: 16px;
    align-items: flex-start;
    margin-bottom: 24px;
}

.contact-item-icon {
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, rgba(26, 86, 219, 0.1), rgba(6, 182, 212, 0.1));
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    flex-shrink: 0;
}

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

.contact-item-content p {
    color: var(--text-gray);
    font-size: 0.95rem;
    margin: 0;
}

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

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

.form-group label {
    display: block;
    font-weight: 500;
    color: var(--text-dark);
    margin-bottom: 8px;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid #e2e8f0;
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: 0.95rem;
    transition: var(--transition);
    background: var(--bg-white);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
}

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

/* ===== 关于页 ===== */
.about-page-hero {
    padding: 160px 0 80px;
    background: var(--bg-gradient);
    color: #fff;
    text-align: center;
}

.about-page-hero h1 {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 16px;
}

.about-page-hero p {
    font-size: 1.2rem;
    opacity: 0.9;
}

/* ===== 404页面 ===== */
.error-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 120px 20px 60px;
    background: var(--bg-gradient);
    color: #fff;
}

.error-content h1 {
    font-size: 10rem;
    font-weight: 800;
    line-height: 1;
    background: linear-gradient(135deg, #60a5fa, #22d3ee);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 20px;
}

.error-content h2 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.error-content p {
    font-size: 1.1rem;
    opacity: 0.85;
    margin-bottom: 40px;
}

.error-content .btn-primary {
    background: linear-gradient(135deg, var(--secondary-color), var(--primary-light));
}

/* ===== 页脚 ===== */
.footer {
    background: var(--bg-dark);
    color: rgba(255, 255, 255, 0.8);
    padding: 80px 0 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 60px;
    margin-bottom: 60px;
}

.footer-brand img {
    width: 50px;
    height: 50px;
    border-radius: 12px;
    margin-bottom: 16px;
}

.footer-brand h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: #fff;
    margin-bottom: 12px;
}

.footer-brand p {
    font-size: 0.9rem;
    line-height: 1.8;
    margin-bottom: 20px;
}

.footer-social {
    display: flex;
    gap: 12px;
}

.footer-social a {
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
    transition: var(--transition);
    color: #fff;
}

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

.footer-col h4 {
    font-size: 1.1rem;
    font-weight: 600;
    color: #fff;
    margin-bottom: 24px;
}

.footer-col ul li {
    margin-bottom: 14px;
}

.footer-col ul li a {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9rem;
    transition: var(--transition);
}

.footer-col ul li a:hover {
    color: var(--secondary-color);
    padding-left: 5px;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 30px;
    text-align: center;
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.5);
}

/* ===== 返回顶部 ===== */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 48px;
    height: 48px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    box-shadow: 0 4px 15px rgba(26, 86, 219, 0.4);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 999;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

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

/* ===== 产品页面 ===== */
.product-hero {
    padding: 160px 0 80px;
    background: var(--bg-gradient);
    color: #fff;
    text-align: center;
}

.product-hero h1 {
    font-size: 2.75rem;
    font-weight: 800;
    margin-bottom: 16px;
}

.product-hero p {
    font-size: 1.15rem;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto;
}

.product-showcase {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
}

.product-item {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--card-shadow);
    transition: var(--transition);
}

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

.product-item-header {
    height: 180px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 4rem;
    color: #fff;
}

.product-item:nth-child(1) .product-item-header {
    background: linear-gradient(135deg, #1a56db, #3b82f6);
}

.product-item:nth-child(2) .product-item-header {
    background: linear-gradient(135deg, #0891b2, #06b6d4);
}

.product-item:nth-child(3) .product-item-header {
    background: linear-gradient(135deg, #059669, #10b981);
}

.product-item:nth-child(4) .product-item-header {
    background: linear-gradient(135deg, #d97706, #f59e0b);
}

.product-item:nth-child(5) .product-item-header {
    background: linear-gradient(135deg, #dc2626, #ef4444);
}

.product-item:nth-child(6) .product-item-header {
    background: linear-gradient(135deg, #7c3aed, #8b5cf6);
}

.product-item-body {
    padding: 32px;
}

.product-item-body h3 {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 12px;
}

.product-item-body p {
    color: var(--text-gray);
    line-height: 1.7;
    margin-bottom: 20px;
}

.product-item-features {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.product-item-features span {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.9rem;
    color: var(--text-dark);
}

.product-item-features span::before {
    content: '✓';
    color: var(--success-color);
    font-weight: 700;
}

/* ===== 面包屑导航 ===== */
.breadcrumb {
    padding: 100px 0 20px;
    background: var(--bg-light);
}

.breadcrumb ol {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}

.breadcrumb li {
    font-size: 0.9rem;
    color: var(--text-gray);
}

.breadcrumb li a {
    color: var(--primary-color);
}

.breadcrumb li + li::before {
    content: '/';
    margin-right: 10px;
    color: var(--text-light);
}

/* ===== 动画 ===== */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ===== 响应式设计 ===== */
@media (max-width: 1024px) {
    .hero-content h1 {
        font-size: 2.75rem;
    }
    
    .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 40px;
    }
    
    .about-grid,
    .contact-grid {
        grid-template-columns: 1fr;
        gap: 50px;
    }
    
    .hero-stats {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-menu,
    .nav-actions .btn-outline {
        display: none;
    }
    
    .nav-menu.open {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #fff;
        padding: 24px;
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
        gap: 16px;
    }
    
    .btn-mobile-toggle {
        display: flex;
    }
    
    .hero {
        padding: 120px 0 80px;
    }
    
    .hero-content {
        text-align: center;
    }
    
    .hero-content h1 {
        font-size: 2.25rem;
    }
    
    .hero-content p {
        font-size: 1rem;
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .hero-stats {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
    }
    
    .stat-item {
        text-align: center;
    }
    
    .section {
        padding: 60px 0;
    }
    
    .section-title h2 {
        font-size: 1.75rem;
    }
    
    .about-page-hero h1,
    .product-hero h1 {
        font-size: 2rem;
    }
    
    .contact-form,
    .news-detail-content {
        padding: 28px;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .about-features {
        grid-template-columns: 1fr;
    }
    
    .error-content h1 {
        font-size: 6rem;
    }
    
    .btn-mobile-toggle.active span:nth-child(1) {
        transform: translateY(7px) rotate(45deg);
    }
    
    .btn-mobile-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    
    .btn-mobile-toggle.active span:nth-child(3) {
        transform: translateY(-7px) rotate(-45deg);
    }
}

@media (max-width: 480px) {
    .hero-content h1 {
        font-size: 1.85rem;
    }
    
    .hero-stats {
        grid-template-columns: 1fr 1fr;
    }
    
    .stat-number {
        font-size: 1.75rem;
    }
    
    .news-list-grid {
        grid-template-columns: 1fr;
    }
    
    .features-grid,
    .services-grid,
    .product-showcase {
        grid-template-columns: 1fr;
    }
    
    .cta h2 {
        font-size: 1.75rem;
    }
}

/* ===== 打印样式 ===== */
@media print {
    .header,
    .footer,
    .back-to-top,
    .cta {
        display: none;
    }
    
    body {
        color: #000;
        background: #fff;
    }
}