```css
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    background: #f9f9fb;
    color: #1a1a2e;
    line-height: 1.7;
    transition: background 0.3s, color 0.3s;
}

body.dark-mode {
    background: #121212;
    color: #e0e0e0;
}

a {
    color: #8B5CF6;
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    color: #6d28d9;
}

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

ul,
ol {
    list-style: none;
}

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

/* 导航吸顶 */
.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(139, 92, 246, 0.15);
    transition: background 0.3s;
}

body.dark-mode .navbar {
    background: rgba(18, 18, 18, 0.95);
    border-bottom-color: rgba(139, 92, 246, 0.3);
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: #8B5CF6;
    letter-spacing: 0.5px;
}

.logo span {
    color: #1a1a2e;
}

body.dark-mode .logo span {
    color: #e0e0e0;
}

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

.nav-links a {
    font-size: 0.95rem;
    font-weight: 500;
    color: #333;
    position: relative;
}

body.dark-mode .nav-links a {
    color: #ccc;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: #8B5CF6;
    transition: width 0.3s;
}

.nav-links a:hover::after {
    width: 100%;
}

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

#darkModeToggle {
    background: none;
    border: 1px solid #ddd;
    border-radius: 20px;
    padding: 0.3rem 0.8rem;
    cursor: pointer;
    font-size: 0.9rem;
    color: #333;
    transition: all 0.2s;
}

body.dark-mode #darkModeToggle {
    border-color: #555;
    color: #ccc;
}

#searchInput {
    padding: 0.4rem 1rem;
    border: 1px solid #ddd;
    border-radius: 20px;
    font-size: 0.9rem;
    width: 180px;
    outline: none;
    transition: border 0.2s;
}

#searchInput:focus {
    border-color: #8B5CF6;
}

body.dark-mode #searchInput {
    background: #2a2a2a;
    border-color: #444;
    color: #eee;
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 1.8rem;
    cursor: pointer;
    color: #333;
}

body.dark-mode .mobile-menu-btn {
    color: #ccc;
}

/* 移动菜单 */
.mobile-nav {
    display: none;
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background: #fff;
    padding: 1rem 1.5rem;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    z-index: 999;
}

body.dark-mode .mobile-nav {
    background: #1a1a1a;
}

.mobile-nav a {
    display: block;
    padding: 0.6rem 0;
    border-bottom: 1px solid #eee;
    font-size: 1rem;
}

body.dark-mode .mobile-nav a {
    border-bottom-color: #333;
}

/* Banner轮播 */
.banner {
    position: relative;
    overflow: hidden;
    background: linear-gradient(135deg, #f5f3ff 0%, #ede9fe 100%);
    min-height: 420px;
    display: flex;
    align-items: center;
}

body.dark-mode .banner {
    background: linear-gradient(135deg, #1e1e2f, #2a2a40);
}

.banner-slides {
    display: flex;
    transition: transform 0.6s ease;
    width: 100%;
}

.banner-slide {
    min-width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 3rem 0;
}

.banner-content {
    text-align: center;
    max-width: 700px;
}

.banner-content h1 {
    font-size: 2.8rem;
    font-weight: 800;
    color: #1a1a2e;
    margin-bottom: 1rem;
    line-height: 1.2;
}

body.dark-mode .banner-content h1 {
    color: #f0f0f0;
}

.banner-content p {
    font-size: 1.2rem;
    color: #555;
    margin-bottom: 2rem;
}

body.dark-mode .banner-content p {
    color: #bbb;
}

.banner-cta {
    display: inline-block;
    background: #8B5CF6;
    color: #fff;
    padding: 0.8rem 2rem;
    border-radius: 30px;
    font-weight: 600;
    transition: background 0.3s;
}

.banner-cta:hover {
    background: #6d28d9;
    color: #fff;
}

.banner-dots {
    position: absolute;
    bottom: 1.5rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 0.6rem;
}

.banner-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(139, 92, 246, 0.3);
    cursor: pointer;
    transition: background 0.3s;
}

.banner-dot.active {
    background: #8B5CF6;
}

/* 通用section */
section {
    padding: 4rem 0;
}

.section-title {
    text-align: center;
    margin-bottom: 3rem;
}

.section-title h2 {
    font-size: 2rem;
    font-weight: 700;
    color: #1a1a2e;
    position: relative;
    display: inline-block;
}

body.dark-mode .section-title h2 {
    color: #f0f0f0;
}

.section-title h2::after {
    content: '';
    display: block;
    width: 60px;
    height: 3px;
    background: #8B5CF6;
    margin: 0.5rem auto 0;
    border-radius: 2px;
}

.section-title p {
    color: #666;
    margin-top: 0.5rem;
    font-size: 1rem;
}

body.dark-mode .section-title p {
    color: #aaa;
}

/* 品牌介绍/企业简介等卡片布局 */
.grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.grid-3 {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 2rem;
}

.grid-4 {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr 1fr;
    gap: 1.5rem;
}

.card {
    background: #fff;
    border-radius: 16px;
    padding: 1.8rem;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
    transition: transform 0.2s, box-shadow 0.2s;
}

body.dark-mode .card {
    background: #1e1e2e;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.2);
}

.card:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(139, 92, 246, 0.1);
}

.card h3 {
    font-size: 1.2rem;
    margin-bottom: 0.8rem;
    color: #1a1a2e;
}

body.dark-mode .card h3 {
    color: #e0e0e0;
}

.card p,
.card li {
    color: #555;
    font-size: 0.95rem;
    line-height: 1.6;
}

body.dark-mode .card p,
body.dark-mode .card li {
    color: #bbb;
}

.card svg {
    margin-bottom: 1rem;
    width: 48px;
    height: 48px;
}

/* 文章卡片 */
.article-card {
    background: #fff;
    border-radius: 16px;
    padding: 1.5rem;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
    transition: transform 0.2s;
}

body.dark-mode .article-card {
    background: #1e1e2e;
}

.article-card h3 {
    font-size: 1.1rem;
    margin-bottom: 0.4rem;
}

.article-card .meta {
    font-size: 0.85rem;
    color: #999;
    margin-bottom: 0.6rem;
}

.article-card p {
    color: #555;
    font-size: 0.9rem;
}

body.dark-mode .article-card p {
    color: #aaa;
}

.read-more {
    color: #8B5CF6;
    font-weight: 500;
    font-size: 0.9rem;
}

/* FAQ */
.faq-item {
    background: #fff;
    border-radius: 12px;
    margin-bottom: 1rem;
    padding: 0 1.5rem;
    box-shadow: 0 1px 6px rgba(0, 0, 0, 0.04);
    overflow: hidden;
}

body.dark-mode .faq-item {
    background: #1e1e2e;
}

.faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.2rem 0;
    cursor: pointer;
    font-weight: 600;
    color: #1a1a2e;
}

body.dark-mode .faq-question {
    color: #e0e0e0;
}

.faq-question::after {
    content: '+';
    font-size: 1.4rem;
    transition: transform 0.3s;
    color: #8B5CF6;
}

.faq-item.active .faq-question::after {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease;
    padding: 0 0 0 0;
    color: #555;
}

body.dark-mode .faq-answer {
    color: #bbb;
}

.faq-item.active .faq-answer {
    max-height: 400px;
    padding: 0 0 1.2rem 0;
}

/* HowTo */
.howto-step {
    display: flex;
    gap: 1.2rem;
    margin-bottom: 1.5rem;
    align-items: flex-start;
}

.step-number {
    background: #8B5CF6;
    color: #fff;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    flex-shrink: 0;
}

.step-content h4 {
    font-size: 1.05rem;
    margin-bottom: 0.3rem;
    color: #1a1a2e;
}

body.dark-mode .step-content h4 {
    color: #e0e0e0;
}

/* 客户评价 */
.testimonial {
    background: #fff;
    border-radius: 16px;
    padding: 1.8rem;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
    position: relative;
}

body.dark-mode .testimonial {
    background: #1e1e2e;
}

.testimonial::before {
    content: '"';
    font-size: 3rem;
    color: #8B5CF6;
    opacity: 0.2;
    position: absolute;
    top: 0.5rem;
    left: 1rem;
}

.testimonial p {
    font-style: italic;
    color: #444;
}

body.dark-mode .testimonial p {
    color: #bbb;
}

.testimonial .author {
    margin-top: 1rem;
    font-weight: 600;
    color: #8B5CF6;
}

/* 联系信息 */
.contact-info {
    display: flex;
    flex-wrap: wrap;
    gap: 1.5rem;
    justify-content: center;
}

.contact-info div {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: #fff;
    padding: 0.8rem 1.5rem;
    border-radius: 30px;
    box-shadow: 0 1px 6px rgba(0, 0, 0, 0.04);
}

body.dark-mode .contact-info div {
    background: #1e1e2e;
}

/* 面包屑 */
.breadcrumb {
    padding: 0.8rem 0;
    font-size: 0.9rem;
    color: #888;
}

.breadcrumb a {
    color: #8B5CF6;
}

.breadcrumb span {
    margin: 0 0.4rem;
}

/* 返回顶部 */
#backToTop {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 48px;
    height: 48px;
    background: #8B5CF6;
    color: #fff;
    border: none;
    border-radius: 50%;
    font-size: 1.4rem;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 12px rgba(139, 92, 246, 0.3);
    z-index: 999;
    transition: opacity 0.3s;
}

#backToTop:hover {
    background: #6d28d9;
}

/* 数字动画 */
.stat-number {
    font-size: 2.5rem;
    font-weight: 800;
    color: #8B5CF6;
}

/* 滚动动画 */
.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* 页脚 */
footer {
    background: #1a1a2e;
    color: #ccc;
    padding: 3rem 0 1.5rem;
    margin-top: 3rem;
}

body.dark-mode footer {
    background: #0d0d1a;
}

footer a {
    color: #a78bfa;
}

footer .footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 2rem;
}

footer h4 {
    color: #fff;
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

footer ul li {
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
}

footer .copyright {
    text-align: center;
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid #333;
    font-size: 0.85rem;
}

/* 响应式 */
@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    .mobile-menu-btn {
        display: block;
    }
    .mobile-nav.open {
        display: block;
    }
    .grid-2,
    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }
    .banner-content h1 {
        font-size: 2rem;
    }
    footer .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
    #searchInput {
        width: 130px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 1rem;
    }
    .banner-content h1 {
        font-size: 1.6rem;
    }
    footer .footer-grid {
        grid-template-columns: 1fr;
    }
}

/* 暗黑模式额外调整 */
body.dark-mode .card,
body.dark-mode .article-card,
body.dark-mode .faq-item,
body.dark-mode .testimonial,
body.dark-mode .contact-info div {
    background: #1e1e2e;
}

body.dark-mode .banner-dot {
    background: rgba(139, 92, 246, 0.4);
}

body.dark-mode .banner-dot.active {
    background: #8B5CF6;
}

body.dark-mode .stat-number {
    color: #a78bfa;
}
```