/* 基础重置与全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    line-height: 1.6;
    color: #222;
    background: #f8f9fa;
    transition: background 0.3s, color 0.3s;
}

a {
    color: #1a73e8;
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    text-decoration: underline;
    color: #d32f2f;
}

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

/* 头部导航 */
header {
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(224, 224, 224, 0.5);
    position: sticky;
    top: 0;
    z-index: 100;
    transition: background 0.3s, border-color 0.3s;
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 0;
    flex-wrap: wrap;
}

.logo {
    font-size: 1.8rem;
    font-weight: 700;
    color: #1a3a5c;
    letter-spacing: -0.5px;
    transition: color 0.3s;
}

.logo span {
    color: #d32f2f;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 20px;
}

nav a {
    color: #333;
    font-weight: 500;
    padding: 5px 10px;
    border-radius: 4px;
    transition: background 0.2s, color 0.2s, transform 0.2s;
    position: relative;
}

nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: #d32f2f;
    transition: width 0.3s, left 0.3s;
}

nav a:hover {
    background: #e8f0fe;
    color: #1a73e8;
    transform: translateY(-2px);
}

nav a:hover::after {
    width: 100%;
    left: 0;
}

.search-box {
    display: flex;
    align-items: center;
    background: rgba(241, 243, 244, 0.8);
    backdrop-filter: blur(4px);
    border-radius: 24px;
    padding: 5px 15px;
    transition: background 0.3s, box-shadow 0.3s;
}

.search-box:focus-within {
    background: #fff;
    box-shadow: 0 0 0 2px #1a73e8;
}

.search-box input {
    border: none;
    background: transparent;
    outline: none;
    padding: 5px;
    font-size: 0.9rem;
    width: 180px;
    transition: width 0.3s;
}

.search-box input:focus {
    width: 220px;
}

.search-box button {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1.2rem;
    color: #555;
    padding: 5px;
    transition: color 0.2s, transform 0.2s;
}

.search-box button:hover {
    color: #d32f2f;
    transform: scale(1.1);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 1.8rem;
    cursor: pointer;
    color: #1a3a5c;
    transition: color 0.2s;
}

.mobile-menu-btn:hover {
    color: #d32f2f;
}

.dark-mode-toggle {
    background: rgba(255, 255, 255, 0.2);
    border: 1px solid rgba(204, 204, 204, 0.5);
    border-radius: 20px;
    padding: 5px 12px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: background 0.3s, border-color 0.3s, transform 0.2s;
    backdrop-filter: blur(4px);
}

.dark-mode-toggle:hover {
    background: rgba(255, 255, 255, 0.4);
    transform: scale(1.05);
}

/* Banner - 渐变背景 */
.banner {
    background: linear-gradient(135deg, #1a3a5c 0%, #2a5a8c 50%, #4a7aac 100%);
    color: #fff;
    padding: 80px 0;
    text-align: center;
    position: relative;
    overflow: hidden;
    animation: gradientShift 8s ease infinite;
    background-size: 200% 200%;
}

@keyframes gradientShift {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

.banner::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: shimmer 10s linear infinite;
}

@keyframes shimmer {
    0% { transform: translate(0, 0); }
    50% { transform: translate(20%, 20%); }
    100% { transform: translate(0, 0); }
}

.banner h1 {
    font-size: 2.5rem;
    margin-bottom: 20px;
    text-shadow: 0 2px 10px rgba(0,0,0,0.3);
    animation: fadeInUp 1s ease;
}

.banner p {
    font-size: 1.2rem;
    max-width: 800px;
    margin: 0 auto 30px;
    opacity: 0.95;
    animation: fadeInUp 1.2s ease;
}

.banner .btn {
    background: linear-gradient(135deg, #d32f2f, #b71c1c);
    color: #fff;
    padding: 14px 35px;
    border-radius: 30px;
    font-weight: 600;
    display: inline-block;
    transition: transform 0.3s, box-shadow 0.3s, background 0.3s;
    box-shadow: 0 4px 15px rgba(211, 47, 47, 0.4);
    animation: fadeInUp 1.4s ease;
}

.banner .btn:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 6px 20px rgba(211, 47, 47, 0.6);
    background: linear-gradient(135deg, #b71c1c, #8e0000);
}

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

/* 通用区块 */
.section {
    padding: 60px 0;
    transition: background 0.3s;
}

.section-title {
    text-align: center;
    margin-bottom: 40px;
}

.section-title h2 {
    font-size: 2rem;
    color: #1a3a5c;
    position: relative;
    display: inline-block;
    padding-bottom: 10px;
    transition: color 0.3s;
}

.section-title h2::after {
    content: '';
    display: block;
    width: 60px;
    height: 3px;
    background: #d32f2f;
    margin: 10px auto 0;
    transition: width 0.3s;
}

.section-title:hover h2::after {
    width: 100px;
}

/* 网格布局 */
.grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
}

.grid-3 {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 30px;
}

.grid-4 {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr 1fr;
    gap: 20px;
}

/* 卡片 - 圆角+毛玻璃 */
.card {
    background: rgba(255, 255, 255, 0.75);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border-radius: 16px;
    padding: 25px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.06), 0 1px 3px rgba(0,0,0,0.04);
    transition: transform 0.3s, box-shadow 0.3s, background 0.3s;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.card:hover {
    transform: translateY(-8px) scale(1.01);
    box-shadow: 0 12px 30px rgba(0,0,0,0.12), 0 4px 8px rgba(0,0,0,0.06);
    background: rgba(255, 255, 255, 0.9);
}

.card h3 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: #1a3a5c;
    transition: color 0.3s;
}

.card p {
    color: #555;
    font-size: 0.95rem;
    line-height: 1.7;
}

/* FAQ */
.faq-item {
    border-bottom: 1px solid rgba(224, 224, 224, 0.5);
    padding: 15px 0;
    transition: border-color 0.3s;
}

.faq-question {
    font-weight: 600;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 1.1rem;
    color: #1a3a5c;
    padding: 5px 0;
    transition: color 0.3s;
}

.faq-question:hover {
    color: #d32f2f;
}

.faq-question::after {
    content: '+';
    font-size: 1.5rem;
    transition: transform 0.3s, color 0.3s;
    color: #1a3a5c;
}

.faq-item.active .faq-question::after {
    transform: rotate(45deg);
    color: #d32f2f;
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease, padding 0.3s ease;
    padding-top: 0;
}

.faq-item.active .faq-answer {
    max-height: 500px;
    padding-top: 15px;
}

.faq-answer p {
    color: #555;
    line-height: 1.8;
}

/* HowTo 步骤 */
.howto-steps {
    counter-reset: step;
}

.howto-step {
    margin-bottom: 20px;
    padding-left: 50px;
    position: relative;
    transition: transform 0.2s;
}

.howto-step:hover {
    transform: translateX(5px);
}

.howto-step::before {
    counter-increment: step;
    content: counter(step);
    position: absolute;
    left: 0;
    top: 0;
    background: linear-gradient(135deg, #1a3a5c, #2a5a8c);
    color: #fff;
    width: 35px;
    height: 35px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    box-shadow: 0 2px 8px rgba(26, 58, 92, 0.3);
    transition: transform 0.3s, box-shadow 0.3s;
}

.howto-step:hover::before {
    transform: scale(1.1);
    box-shadow: 0 4px 12px rgba(26, 58, 92, 0.5);
}

.howto-step h4 {
    font-size: 1.1rem;
    color: #1a3a5c;
    margin-bottom: 5px;
    transition: color 0.3s;
}

.howto-step p {
    color: #555;
    line-height: 1.7;
}

/* 文章列表 */
.article-list article {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(6px);
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 20px;
    box-shadow: 0 1px 4px rgba(0,0,0,0.06);
    transition: transform 0.3s, box-shadow 0.3s, background 0.3s;
    border: 1px solid rgba(255, 255, 255, 0.15);
}

.article-list article:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 20px rgba(0,0,0,0.1);
    background: rgba(255, 255, 255, 0.9);
}

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

.article-list article h3 a {
    color: #1a3a5c;
    transition: color 0.2s;
}

.article-list article h3 a:hover {
    color: #d32f2f;
}

.article-list article .meta {
    font-size: 0.85rem;
    color: #888;
    margin-bottom: 10px;
}

.article-list article p {
    color: #555;
}

.read-more {
    color: #d32f2f;
    font-weight: 500;
    display: inline-block;
    transition: transform 0.2s, color 0.2s;
}

.read-more:hover {
    transform: translateX(5px);
    color: #b71c1c;
}

/* 页脚 */
.footer {
    background: linear-gradient(135deg, #1a3a5c, #0d1b2a);
    color: #ccc;
    padding: 40px 0;
    position: relative;
}

.footer a {
    color: #bbb;
    transition: color 0.2s, transform 0.2s;
    display: inline-block;
}

.footer a:hover {
    color: #fff;
    transform: translateX(3px);
}

.footer .grid-4 {
    gap: 30px;
}

.footer h4 {
    color: #fff;
    margin-bottom: 15px;
    font-size: 1.1rem;
    position: relative;
    padding-bottom: 8px;
}

.footer h4::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 30px;
    height: 2px;
    background: #d32f2f;
}

.footer ul {
    list-style: none;
}

.footer ul li {
    margin-bottom: 8px;
}

.footer-bottom {
    border-top: 1px solid rgba(42, 74, 108, 0.5);
    padding-top: 20px;
    margin-top: 30px;
    text-align: center;
    font-size: 0.9rem;
}

.footer-bottom a {
    color: #bbb;
}

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

/* 返回顶部 */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    background: linear-gradient(135deg, #1a3a5c, #2a5a8c);
    color: #fff;
    width: 45px;
    height: 45px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 1.5rem;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
    z-index: 99;
    opacity: 0;
    transition: opacity 0.3s, transform 0.3s, box-shadow 0.3s;
    border: none;
}

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

.back-to-top:hover {
    transform: translateY(-3px) scale(1.1);
    box-shadow: 0 6px 20px rgba(0,0,0,0.3);
}

/* SVG 图标 */
.svg-icon {
    width: 48px;
    height: 48px;
    fill: #1a3a5c;
    margin-bottom: 15px;
    transition: fill 0.3s, transform 0.3s;
}

.card:hover .svg-icon {
    transform: scale(1.1) rotate(5deg);
    fill: #d32f2f;
}

/* 客户Logo */
.client-logos {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    justify-content: center;
    padding: 20px 0;
}

.client-logos svg {
    width: 80px;
    height: 40px;
    fill: #aaa;
    transition: fill 0.3s, transform 0.3s;
    cursor: pointer;
}

.client-logos svg:hover {
    fill: #1a3a5c;
    transform: scale(1.1);
}

/* 新闻通讯 */
.newsletter {
    background: rgba(232, 240, 254, 0.7);
    backdrop-filter: blur(8px);
    padding: 30px;
    border-radius: 16px;
    text-align: center;
    transition: background 0.3s;
}

.newsletter h3 {
    color: #1a3a5c;
    margin-bottom: 10px;
}

.newsletter p {
    color: #555;
    margin-bottom: 20px;
}

.newsletter input {
    padding: 12px 20px;
    border: 1px solid rgba(204, 204, 204, 0.5);
    border-radius: 30px;
    width: 250px;
    max-width: 80%;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(4px);
    transition: border-color 0.3s, box-shadow 0.3s;
    outline: none;
}

.newsletter input:focus {
    border-color: #1a73e8;
    box-shadow: 0 0 0 3px rgba(26, 115, 232, 0.2);
}

.newsletter button {
    padding: 12px 25px;
    background: linear-gradient(135deg, #d32f2f, #b71c1c);
    color: #fff;
    border: none;
    border-radius: 30px;
    cursor: pointer;
    margin-left: 10px;
    font-weight: 600;
    transition: transform 0.3s, box-shadow 0.3s;
    box-shadow: 0 2px 8px rgba(211, 47, 47, 0.3);
}

.newsletter button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(211, 47, 47, 0.5);
}

/* 暗色模式 */
body.dark {
    background: #121212;
    color: #e0e0e0;
}

body.dark header {
    background: rgba(30, 30, 30, 0.9);
    backdrop-filter: blur(12px);
    border-bottom-color: rgba(51, 51, 51, 0.5);
}

body.dark .logo {
    color: #90caf9;
}

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

body.dark nav a:hover {
    background: rgba(144, 202, 249, 0.1);
    color: #90caf9;
}

body.dark .search-box {
    background: rgba(51, 51, 51, 0.8);
}

body.dark .search-box input {
    color: #eee;
}

body.dark .search-box input::placeholder {
    color: #888;
}

body.dark .card {
    background: rgba(30, 30, 30, 0.8);
    backdrop-filter: blur(8px);
    border-color: rgba(255, 255, 255, 0.05);
    color: #ddd;
}

body.dark .card:hover {
    background: rgba(40, 40, 40, 0.9);
}

body.dark .card h3 {
    color: #90caf9;
}

body.dark .card p {
    color: #bbb;
}

body.dark .section-title h2 {
    color: #90caf9;
}

body.dark .faq-question {
    color: #90caf9;
}

body.dark .faq-question::after {
    color: #90caf9;
}

body.dark .footer {
    background: linear-gradient(135deg, #0d1b2a, #1a1a2e);
}

body.dark .banner {
    background: linear-gradient(135deg, #0d1b2a, #1a3a5c, #2a5a8c);
}

body.dark .article-list article {
    background: rgba(30, 30, 30, 0.7);
    backdrop-filter: blur(6px);
    border-color: rgba(255, 255, 255, 0.05);
}

body.dark .article-list article:hover {
    background: rgba(40, 40, 40, 0.9);
}

body.dark .article-list article h3 a {
    color: #90caf9;
}

body.dark .article-list article .meta {
    color: #888;
}

body.dark .article-list article p {
    color: #bbb;
}

body.dark .svg-icon {
    fill: #90caf9;
}

body.dark .card:hover .svg-icon {
    fill: #d32f2f;
}

body.dark .newsletter {
    background: rgba(30, 42, 58, 0.7);
}

body.dark .newsletter h3 {
    color: #90caf9;
}

body.dark .newsletter p {
    color: #bbb;
}

body.dark .newsletter input {
    background: rgba(51, 51, 51, 0.8);
    border-color: rgba(204, 204, 204, 0.3);
    color: #eee;
}

body.dark .newsletter input:focus {
    border-color: #90caf9;
    box-shadow: 0 0 0 3px rgba(144, 202, 249, 0.2);
}

body.dark .dark-mode-toggle {
    border-color: rgba(204, 204, 204, 0.3);
    color: #eee;
}

body.dark .dark-mode-toggle:hover {
    background: rgba(255, 255, 255, 0.1);
}

body.dark .mobile-menu-btn {
    color: #90caf9;
}

body.dark .howto-step h4 {
    color: #90caf9;
}

body.dark .howto-step p {
    color: #bbb;
}

body.dark .howto-step::before {
    background: linear-gradient(135deg, #1a3a5c, #2a5a8c);
}

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

body.dark .faq-item {
    border-bottom-color: rgba(51, 51, 51, 0.5);
}

body.dark .client-logos svg:hover {
    fill: #90caf9;
}

/* 滚动动画 - 配合JS */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.animate-on-scroll.animated {
    opacity: 1;
    transform: translateY(0);
}

/* 响应式布局 */
@media (max-width: 768px) {
    nav ul {
        display: none;
        flex-direction: column;
        background: rgba(255, 255, 255, 0.95);
        backdrop-filter: blur(12px);
        position: absolute;
        top: 60px;
        left: 0;
        width: 100%;
        padding: 20px;
        box-shadow: 0 4px 20px rgba(0,0,0,0.1);
        border-radius: 0 0 12px 12px;
        z-index: 99;
    }

    body.dark nav ul {
        background: rgba(30, 30, 30, 0.95);
    }

    nav ul.show {
        display: flex;
    }

    .mobile-menu-btn {
        display: block;
    }

    .grid-2, .grid-3, .grid-4 {
        grid-template-columns: 1fr;
    }

    .banner h1 {
        font-size: 1.8rem;
    }

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

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

    .search-box input:focus {
        width: 150px;
    }

    .header-inner {
        gap: 10px;
    }

    .section {
        padding: 40px 0;
    }

    .section-title h2 {
        font-size: 1.6rem;
    }

    .card {
        padding: 20px;
    }

    .footer .grid-4 {
        grid-template-columns: 1fr 1fr;
    }

    .newsletter input {
        width: 100%;
        margin-bottom: 10px;
    }

    .newsletter button {
        margin-left: 0;
        width: 100%;
    }

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

@media (max-width: 480px) {
    .logo {
        font-size: 1.4rem;
    }

    .banner {
        padding: 50px 0;
    }

    .banner h1 {
        font-size: 1.5rem;
    }

    .banner .btn {
        padding: 10px 25px;
        font-size: 0.9rem;
    }

    .footer .grid-4 {
        grid-template-columns: 1fr;
    }

    .search-box input {
        width: 80px;
    }

    .search-box input:focus {
        width: 100px;
    }
}

/* 额外动画 */
.card, .article-list article, .faq-item, .howto-step {
    animation: fadeInUp 0.6s ease forwards;
    opacity: 0;
}

.card:nth-child(1) { animation-delay: 0.1s; }
.card:nth-child(2) { animation-delay: 0.2s; }
.card:nth-child(3) { animation-delay: 0.3s; }
.card:nth-child(4) { animation-delay: 0.4s; }

.article-list article:nth-child(1) { animation-delay: 0.1s; }
.article-list article:nth-child(2) { animation-delay: 0.2s; }
.article-list article:nth-child(3) { animation-delay: 0.3s; }
.article-list article:nth-child(4) { animation-delay: 0.4s; }
.article-list article:nth-child(5) { animation-delay: 0.5s; }
.article-list article:nth-child(6) { animation-delay: 0.6s; }
.article-list article:nth-child(7) { animation-delay: 0.7s; }
.article-list article:nth-child(8) { animation-delay: 0.8s; }
.article-list article:nth-child(9) { animation-delay: 0.9s; }
.article-list article:nth-child(10) { animation-delay: 1s; }

/* 块引用样式 */
blockquote {
    border-left: 4px solid #d32f2f;
    padding-left: 20px;
    margin: 20px 0;
    font-style: italic;
    color: #555;
    background: rgba(211, 47, 47, 0.05);
    border-radius: 0 8px 8px 0;
    padding: 15px 20px;
    transition: background 0.3s;
}

body.dark blockquote {
    color: #bbb;
    background: rgba(211, 47, 47, 0.1);
}

/* 列表样式 */
ul[style*="list-style:disc"] {
    padding-left: 20px;
    color: #555;
    line-height: 2;
}

body.dark ul[style*="list-style:disc"] {
    color: #bbb;
}

/* 联系方式内联样式增强 */
.section p strong {
    color: #1a3a5c;
}

body.dark .section p strong {
    color: #90caf9;
}