/* 全局重置与基础设置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', 'PingFang SC', Roboto, sans-serif;
    background: #f0f4f8;
    color: #1a2a3a;
    line-height: 1.6;
    transition: background 0.3s, color 0.3s;
}

body.dark {
    background: #0b1a2e;
    color: #e0e8f0;
}

a {
    color: #1e6f9f;
    text-decoration: none;
    transition: color 0.2s;
}

body.dark a {
    color: #7ab8e0;
}

a:hover {
    color: #165a7a;
}

body.dark a:hover {
    color: #a0d0f0;
}

/* 容器 */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

/* 玻璃拟态卡片 */
.glass-card {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-radius: 24px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
    padding: 32px;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

body.dark .glass-card {
    background: rgba(20, 40, 60, 0.7);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.glass-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.12);
}

body.dark .glass-card:hover {
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4);
}

/* 渐变背景 */
.gradient-bg {
    background: linear-gradient(135deg, #1e3a5f 0%, #2a5f8a 50%, #4a8bc2 100%);
}

body.dark .gradient-bg {
    background: linear-gradient(135deg, #0a1628 0%, #1a2e4a 50%, #2a4a6a 100%);
}

/* 导航 */
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    transition: background 0.3s, box-shadow 0.3s;
}

body.dark header {
    background: rgba(10, 20, 35, 0.85);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 24px;
    max-width: 1280px;
    margin: 0 auto;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo svg {
    width: 48px;
    height: 48px;
}

.logo span {
    font-size: 1.6rem;
    font-weight: 700;
    background: linear-gradient(135deg, #1e3a5f, #4a8bc2);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

body.dark .logo span {
    background: linear-gradient(135deg, #7ab8e0, #c0d8f0);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    gap: 32px;
    list-style: none;
}

.nav-links a {
    font-weight: 500;
    font-size: 1rem;
    color: #1a2a3a;
    transition: color 0.2s, font-weight 0.2s;
}

body.dark .nav-links a {
    color: #c0d0e0;
}

.nav-links a:hover {
    color: #1e6f9f;
}

body.dark .nav-links a:hover {
    color: #7ab8e0;
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.8rem;
    cursor: pointer;
    color: #1a2a3a;
    transition: color 0.2s;
}

body.dark .menu-toggle {
    color: #e0e8f0;
}

/* 搜索 */
.search-box {
    display: flex;
    align-items: center;
    gap: 8px;
}

.search-box input {
    padding: 8px 16px;
    border-radius: 40px;
    border: 1px solid #ccc;
    background: rgba(255, 255, 255, 0.6);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    font-size: 0.9rem;
    width: 180px;
    transition: width 0.3s ease, border-color 0.2s;
    color: #1a2a3a;
}

body.dark .search-box input {
    background: rgba(30, 50, 70, 0.6);
    border-color: #3a5a7a;
    color: #e0e8f0;
}

.search-box input:focus {
    width: 240px;
    outline: none;
    border-color: #1e6f9f;
}

body.dark .search-box input:focus {
    border-color: #7ab8e0;
}

.search-box button {
    background: #1e6f9f;
    color: #fff;
    border: none;
    border-radius: 40px;
    padding: 8px 16px;
    cursor: pointer;
    font-weight: 500;
    transition: background 0.2s;
}

.search-box button:hover {
    background: #165a7a;
}

body.dark .search-box button {
    background: #2a5f8a;
}

body.dark .search-box button:hover {
    background: #1e4a6a;
}

/* 暗黑切换 */
.dark-toggle {
    background: none;
    border: none;
    font-size: 1.4rem;
    cursor: pointer;
    padding: 4px;
    color: #1a2a3a;
    transition: color 0.2s;
}

body.dark .dark-toggle {
    color: #e0e8f0;
}

/* Banner */
.banner {
    padding-top: 100px;
    position: relative;
    overflow: hidden;
    min-height: 500px;
    display: flex;
    align-items: center;
}

.banner-slide {
    display: none;
    animation: fadeIn 0.8s ease;
}

.banner-slide.active {
    display: flex;
    align-items: center;
    gap: 40px;
    flex-wrap: wrap;
}

.banner-text {
    flex: 1;
    min-width: 280px;
}

.banner-text h1 {
    font-size: 2.8rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 16px;
}

.banner-text p {
    font-size: 1.2rem;
    opacity: 0.85;
    margin-bottom: 24px;
}

.banner-text .btn {
    display: inline-block;
    background: #1e6f9f;
    color: #fff;
    padding: 14px 36px;
    border-radius: 40px;
    font-weight: 600;
    transition: background 0.2s, transform 0.2s;
}

.banner-text .btn:hover {
    background: #165a7a;
    transform: scale(1.05);
}

body.dark .banner-text .btn {
    background: #2a5f8a;
}

body.dark .banner-text .btn:hover {
    background: #1e4a6a;
}

.banner-visual {
    flex: 1;
    min-width: 280px;
    text-align: center;
}

.banner-visual svg {
    max-width: 100%;
    height: auto;
}

.banner-controls {
    position: absolute;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 12px;
}

.banner-controls button {
    width: 14px;
    height: 14px;
    border-radius: 50%;
    border: none;
    background: rgba(255, 255, 255, 0.4);
    cursor: pointer;
    transition: background 0.3s, transform 0.2s;
}

.banner-controls button.active {
    background: #fff;
}

.banner-controls button:hover {
    transform: scale(1.2);
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 通用section */
section {
    padding: 80px 0;
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 40px;
    text-align: center;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: #1e6f9f;
    margin: 12px auto 0;
    border-radius: 4px;
}

body.dark .section-title::after {
    background: #7ab8e0;
}

/* 网格布局 */
.grid-2 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 32px;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
}

.grid-4 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

/* 团队 */
.team-card {
    text-align: center;
}

.team-card svg {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    margin-bottom: 16px;
}

/* 合作伙伴 */
.partner-item {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 16px;
}

.partner-item svg {
    max-width: 120px;
    height: 60px;
}

/* 评价 */
.review-card {
    font-style: italic;
}

.review-card .author {
    font-weight: 600;
    margin-top: 12px;
}

/* 新闻 */
.article-card {
    cursor: pointer;
}

.article-card h3 {
    font-size: 1.2rem;
    margin-bottom: 8px;
}

.article-card .date {
    font-size: 0.85rem;
    opacity: 0.7;
}

.article-card .summary {
    margin-top: 8px;
}

.article-card .read-more {
    color: #1e6f9f;
    font-weight: 500;
    transition: color 0.2s;
}

body.dark .article-card .read-more {
    color: #7ab8e0;
}

.article-card .read-more:hover {
    color: #165a7a;
}

body.dark .article-card .read-more:hover {
    color: #a0d0f0;
}

/* FAQ */
.faq-item {
    border-bottom: 1px solid rgba(0, 0, 0, 0.08);
    padding: 16px 0;
    cursor: pointer;
    transition: background 0.2s;
}

body.dark .faq-item {
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.faq-item:hover {
    background: rgba(0, 0, 0, 0.02);
}

body.dark .faq-item:hover {
    background: rgba(255, 255, 255, 0.02);
}

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

.faq-question span {
    transition: transform 0.3s;
}

.faq-item.open .faq-question span {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease, padding-top 0.4s ease;
    padding-top: 0;
}

.faq-item.open .faq-answer {
    max-height: 300px;
    padding-top: 12px;
}

/* HowTo */
.howto-step {
    display: flex;
    gap: 16px;
    margin-bottom: 16px;
}

.howto-step .step-num {
    background: #1e6f9f;
    color: #fff;
    border-radius: 50%;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    flex-shrink: 0;
}

body.dark .howto-step .step-num {
    background: #2a5f8a;
}

/* 联系我们 */
.contact-info p {
    margin-bottom: 8px;
}

/* 页脚 */
footer {
    background: #0b1a2e;
    color: #b0c8e0;
    padding: 48px 0 24px;
}

body.dark footer {
    background: #050e1a;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 32px;
    margin-bottom: 32px;
}

.footer-grid h4 {
    color: #fff;
    margin-bottom: 16px;
}

.footer-grid a {
    display: block;
    margin-bottom: 8px;
    color: #b0c8e0;
    transition: color 0.2s;
}

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

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 24px;
    text-align: center;
    font-size: 0.9rem;
}

/* 返回顶部 */
.back-to-top {
    position: fixed;
    bottom: 40px;
    right: 40px;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: #1e6f9f;
    color: #fff;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    opacity: 0;
    transition: opacity 0.3s, transform 0.2s;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
    z-index: 999;
}

body.dark .back-to-top {
    background: #2a5f8a;
}

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

.back-to-top:hover {
    transform: scale(1.1);
}

/* 响应式 */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        flex-direction: column;
        background: rgba(255, 255, 255, 0.95);
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        padding: 24px;
        gap: 16px;
        box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1);
    }

    body.dark .nav-links {
        background: rgba(10, 20, 35, 0.95);
    }

    .nav-links.open {
        display: flex;
    }

    .menu-toggle {
        display: block;
    }

    .search-box input {
        width: 120px;
    }

    .search-box input:focus {
        width: 160px;
    }

    .banner-text h1 {
        font-size: 2rem;
    }

    .banner-slide.active {
        flex-direction: column;
    }

    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 40px;
        height: 40px;
        font-size: 1.2rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }

    .banner-text h1 {
        font-size: 1.6rem;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .glass-card {
        padding: 24px;
    }
}

/* 滚动动画 */
.fade-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* 数字增长 */
.stat-number {
    font-size: 2.4rem;
    font-weight: 800;
    color: #1e6f9f;
}

body.dark .stat-number {
    color: #7ab8e0;
}

/* 面包屑 */
.breadcrumb {
    padding: 16px 0;
    font-size: 0.9rem;
    color: #666;
}

body.dark .breadcrumb {
    color: #a0b0c0;
}

.breadcrumb a {
    color: #1e6f9f;
}

body.dark .breadcrumb a {
    color: #7ab8e0;
}

/* 额外动画与细节 */
.banner-visual svg {
    transition: transform 0.3s;
}

.banner-visual svg:hover {
    transform: scale(1.02);
}

.nav-links a {
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: #1e6f9f;
    transition: width 0.3s;
}

body.dark .nav-links a::after {
    background: #7ab8e0;
}

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

/* 图片懒加载占位 */
img[loading="lazy"] {
    opacity: 0;
    transition: opacity 0.3s;
}

img[loading="lazy"].loaded {
    opacity: 1;
}