/* ===== 全局重置 & 基础 ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
}

body {
    background: #f8fafc;
    color: #1e293b;
    line-height: 1.6;
    transition: background 0.3s, color 0.3s;
}

body.dark {
    background: #0f172a;
    color: #e2e8f0;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== 头部 ===== */
header {
    background: linear-gradient(135deg, #1e3a8a, #3b82f6);
    color: #fff;
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    backdrop-filter: blur(10px);
    background: rgba(30, 58, 138, 0.9);
}

body.dark header {
    background: rgba(15, 23, 42, 0.9);
}

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

.logo {
    font-size: 1.8rem;
    font-weight: 700;
    background: linear-gradient(135deg, #fbbf24, #f59e0b);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

nav a {
    color: #fff;
    text-decoration: none;
    margin: 0 1rem;
    font-weight: 500;
    transition: color 0.3s;
}

nav a:hover {
    color: #fbbf24;
}

body.dark nav a {
    color: #e2e8f0;
}

body.dark nav a:hover {
    color: #fbbf24;
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    color: #fff;
    font-size: 1.5rem;
    cursor: pointer;
}

.dark-toggle {
    background: none;
    border: none;
    color: #fff;
    font-size: 1.3rem;
    cursor: pointer;
    padding: 0.5rem;
}

/* ===== 面包屑 ===== */
.breadcrumb {
    background: #f1f5f9;
    padding: 0.8rem 0;
    font-size: 0.9rem;
}

body.dark .breadcrumb {
    background: #1e293b;
}

.breadcrumb a {
    color: #3b82f6;
    text-decoration: none;
}

body.dark .breadcrumb a {
    color: #fbbf24;
}

.breadcrumb span {
    color: #64748b;
}

body.dark .breadcrumb span {
    color: #94a3b8;
}

/* ===== Hero ===== */
.hero {
    background: linear-gradient(135deg, #1e3a8a, #3b82f6, #06b6d4);
    color: #fff;
    padding: 6rem 0;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
    animation: pulse 4s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    animation: fadeInUp 1s ease;
}

.hero p {
    font-size: 1.3rem;
    max-width: 700px;
    margin: 0 auto 2rem;
    animation: fadeInUp 1.2s ease;
}

.hero .btn {
    display: inline-block;
    background: #fbbf24;
    color: #1e3a8a;
    padding: 1rem 2.5rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 700;
    transition: transform 0.3s, box-shadow 0.3s;
}

.hero .btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 30px rgba(251, 191, 36, 0.4);
}

/* ===== 轮播 ===== */
.slider {
    overflow: hidden;
    position: relative;
    height: 500px;
}

.slider-inner {
    display: flex;
    transition: transform 0.5s ease;
}

.slider-item {
    min-width: 100%;
    height: 500px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #1e3a8a, #3b82f6);
    color: #fff;
    font-size: 2rem;
    font-weight: 700;
}

.slider-controls {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 10px;
}

.slider-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    cursor: pointer;
    transition: background 0.3s;
}

.slider-dot.active {
    background: #fbbf24;
}

/* ===== 通用区块 ===== */
.section {
    padding: 5rem 0;
}

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 3rem;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 80px;
    height: 4px;
    background: linear-gradient(135deg, #3b82f6, #06b6d4);
    margin: 1rem auto;
    border-radius: 2px;
}

body.dark .section-title::after {
    background: linear-gradient(135deg, #fbbf24, #f59e0b);
}

/* ===== 网格 & 卡片 ===== */
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.card {
    background: #fff;
    border-radius: 20px;
    padding: 2rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s, box-shadow 0.3s;
    backdrop-filter: blur(10px);
    background: rgba(255, 255, 255, 0.9);
}

.card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.15);
}

body.dark .card {
    background: rgba(30, 41, 59, 0.9);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

body.dark .card:hover {
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
}

.card-icon {
    width: 60px;
    height: 60px;
    margin-bottom: 1rem;
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
}

.card h3 {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
}

.card p {
    color: #64748b;
    font-size: 0.95rem;
}

body.dark .card p {
    color: #94a3b8;
}

/* ===== 统计数据 ===== */
.stats {
    background: linear-gradient(135deg, #1e3a8a, #3b82f6);
    color: #fff;
    padding: 4rem 0;
}

.stats .grid {
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

.stat-item {
    text-align: center;
    padding: 2rem;
}

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

.stat-label {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* ===== 客户评价 ===== */
.testimonial-card {
    background: #fff;
    border-radius: 20px;
    padding: 2rem;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    text-align: center;
}

body.dark .testimonial-card {
    background: rgba(30, 41, 59, 0.9);
}

.testimonial-card img {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    margin-bottom: 1rem;
    object-fit: cover;
}

.testimonial-card h4 {
    font-weight: 600;
}

.testimonial-card p {
    color: #64748b;
    font-style: italic;
    margin: 1rem 0;
}

body.dark .testimonial-card p {
    color: #94a3b8;
}

/* ===== FAQ ===== */
.faq-item {
    border-bottom: 1px solid #e2e8f0;
    padding: 1rem 0;
    cursor: pointer;
}

body.dark .faq-item {
    border-color: #334155;
}

.faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-weight: 600;
    font-size: 1.1rem;
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    color: #64748b;
    padding-top: 0.5rem;
}

body.dark .faq-answer {
    color: #94a3b8;
}

.faq-item.active .faq-answer {
    max-height: 300px;
}

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

.faq-icon {
    transition: transform 0.3s;
    font-size: 1.5rem;
}

/* ===== 联系信息 ===== */
.contact-info {
    background: linear-gradient(135deg, #1e3a8a, #3b82f6);
    color: #fff;
    padding: 3rem;
    border-radius: 20px;
    text-align: center;
}

.contact-info p {
    margin: 0.5rem 0;
    font-size: 1.1rem;
}

/* ===== 页脚 ===== */
footer {
    background: #0f172a;
    color: #94a3b8;
    padding: 3rem 0 1rem;
}

footer a {
    color: #94a3b8;
    text-decoration: none;
    transition: color 0.3s;
}

footer a:hover {
    color: #fbbf24;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-grid h4 {
    color: #fff;
    margin-bottom: 1rem;
}

.footer-grid ul {
    list-style: none;
}

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

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #1e293b;
}

/* ===== 回到顶部 ===== */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: #3b82f6;
    color: #fff;
    border: none;
    cursor: pointer;
    font-size: 1.5rem;
    display: none;
    align-items: center;
    justify-content: center;
    box-shadow: 0 5px 20px rgba(59, 130, 246, 0.4);
    transition: background 0.3s, transform 0.3s;
    z-index: 999;
}

.back-to-top:hover {
    background: #1e3a8a;
    transform: translateY(-3px);
}

body.dark .back-to-top {
    background: #fbbf24;
    color: #1e3a8a;
    box-shadow: 0 5px 20px rgba(251, 191, 36, 0.4);
}

body.dark .back-to-top:hover {
    background: #f59e0b;
}

/* ===== 搜索栏 ===== */
.search-bar {
    display: flex;
    max-width: 400px;
    margin: 0 auto 2rem;
}

.search-bar input {
    flex: 1;
    padding: 0.8rem 1rem;
    border: 2px solid #e2e8f0;
    border-radius: 50px 0 0 50px;
    outline: none;
    font-size: 1rem;
}

body.dark .search-bar input {
    background: #1e293b;
    border-color: #334155;
    color: #e2e8f0;
}

.search-bar button {
    padding: 0.8rem 1.5rem;
    background: #3b82f6;
    color: #fff;
    border: none;
    border-radius: 0 50px 50px 0;
    cursor: pointer;
    transition: background 0.3s;
}

.search-bar button:hover {
    background: #1e3a8a;
}

/* ===== 文章导航 ===== */
.article-nav {
    display: flex;
    justify-content: space-between;
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid #e2e8f0;
}

body.dark .article-nav {
    border-color: #334155;
}

.article-nav a {
    color: #3b82f6;
    text-decoration: none;
    font-weight: 500;
}

body.dark .article-nav a {
    color: #fbbf24;
}

/* ===== 动画 & 滚动 ===== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s, transform 0.6s;
}

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

.lazy {
    opacity: 0;
    transition: opacity 0.3s;
}

.lazy.loaded {
    opacity: 1;
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .menu-toggle {
        display: block;
    }

    nav {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: rgba(30, 58, 138, 0.95);
        padding: 1rem;
    }

    nav.active {
        display: flex;
    }

    nav a {
        margin: 0.5rem 0;
    }

    .hero h1 {
        font-size: 2.2rem;
    }

    .hero p {
        font-size: 1rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .slider {
        height: 300px;
    }

    .slider-item {
        height: 300px;
        font-size: 1.5rem;
    }
}