/* ===== CSS 变量 ===== */
:root {
    --primary: #0077C3;
    --primary-light: #00A8E8;
    --dark-bg: #1A2A3A;
    --light-bg: #F5F9FF;
    --highlight: #FF6B35;
    --success: #2DCA8C;
    --text-primary: #1A2A3A;
    --text-secondary: #5A6A7A;
    --card-bg: #ffffff;
    --border-color: #e0e8f0;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    --radius: 12px;
}

[data-theme="dark"] {
    --text-primary: #E8F0F8;
    --text-secondary: #9AACB8;
    --card-bg: #161B22;
    --border-color: #2D3748;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

[data-theme="dark"] body {
    background-color: #0D1117;
}

body {
    margin: 0;
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    color: var(--text-primary);
    background-color: var(--light-bg);
    line-height: 1.6;
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 12px 0;
    transition: background 0.3s, backdrop-filter 0.3s;
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(12px);
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] .navbar.scrolled {
    background: rgba(13, 17, 23, 0.85);
}

.navbar-inner {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    gap: 32px;
}

.navbar-logo {
    display: flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
}

.navbar-logo span {
    color: var(--primary);
    font-weight: 700;
    font-size: 18px;
}

.navbar-logo img {
    height: 32px;
}

.navbar-links {
    display: flex;
    gap: 24px;
    margin-left: auto;
}

.navbar-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: color 0.2s;
}

.navbar-links a:hover {
    color: var(--primary);
}

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

.theme-toggle {
    background: none;
    border: none;
    font-size: 18px;
    cursor: pointer;
    padding: 6px 10px;
    border-radius: 50%;
    transition: background 0.2s, transform 0.2s;
}

.theme-toggle:hover {
    background: var(--border-color);
    transform: scale(1.1);
}

.btn-download {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    color: #fff !important;
    text-decoration: none;
    padding: 8px 20px;
    border-radius: 20px;
    font-weight: 600;
    font-size: 14px;
    transition: all 0.3s;
    box-shadow: 0 2px 12px rgba(0, 119, 195, 0.3);
}

.btn-download:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 20px rgba(0, 119, 195, 0.5);
    background: linear-gradient(135deg, var(--primary-light) 0%, var(--primary) 100%);
}

/* ===== 通用按钮 ===== */
.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.2s;
    cursor: pointer;
    border: none;
    font-size: 16px;
}

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

.btn-primary:hover {
    background: var(--primary-light);
    transform: translateY(-2px);
}

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

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

/* ===== Section 通用 ===== */
section {
    padding: 80px 24px;
}

.section-header {
    text-align: center;
    margin-bottom: 48px;
}

.section-header h2 {
    font-size: 36px;
    margin: 0 0 12px;
    color: var(--text-primary);
}

/* ===== Hero 首屏 ===== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 80px;
    background: linear-gradient(135deg, var(--light-bg) 0%, #D6E8F8 100%);
}

[data-theme="dark"] .hero {
    background: linear-gradient(135deg, #0D1117 0%, #161B22 100%);
}

.hero-inner {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    align-items: center;
}

.hero-title {
    font-size: 48px;
    line-height: 1.2;
    margin: 0 0 16px;
    color: var(--text-primary);
}

.hero-subtitle {
    font-size: 18px;
    color: var(--text-secondary);
    margin: 0 0 24px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    margin-bottom: 24px;
}

.hero-users {
    font-size: 16px;
    color: var(--text-secondary);
}

.hero-screenshot {
    width: 100%;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

/* ===== AI 演示区 ===== */
.ai-demo {
    background: var(--card-bg);
}

.ai-demo-inner {
    max-width: 1000px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 32px;
    align-items: center;
}

.chat-panel {
    background: var(--light-bg);
    border-radius: var(--radius);
    padding: 24px;
    min-height: 200px;
}

[data-theme="dark"] .chat-panel {
    background: #161B22;
}

.chat-bubble {
    background: var(--primary);
    color: #fff;
    padding: 16px 20px;
    border-radius: 16px 16px 16px 4px;
    font-size: 16px;
    min-height: 24px;
}

.video-panel video {
    width: 100%;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.ai-demo-footer {
    text-align: center;
    margin-top: 32px;
}

/* ===== 定价区 ===== */
.pricing {
    background: var(--light-bg);
}

[data-theme="dark"] .pricing {
    background: #0D1117;
}

.pricing-calculator {
    max-width: 600px;
    margin: 0 auto 48px;
    text-align: center;
}

.slider-label {
    display: block;
    font-size: 18px;
    margin-bottom: 16px;
}

.pricing-slider {
    width: 100%;
    height: 8px;
    border-radius: 4px;
    background: var(--border-color);
    outline: none;
    -webkit-appearance: none;
    margin-bottom: 24px;
}

.pricing-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--primary);
    cursor: pointer;
    box-shadow: 0 2px 8px rgba(0, 119, 195, 0.3);
}

.price-display {
    padding: 20px;
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.price-amount {
    font-size: 24px;
}

.price-note {
    font-size: 14px;
    color: var(--success);
    margin: 8px 0 0;
}

.pricing-cards {
    max-width: 800px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.pricing-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 32px;
    box-shadow: var(--shadow);
    border: 2px solid var(--border-color);
}

.pricing-card.featured {
    border-color: var(--primary);
}

.pricing-card h3 {
    margin: 0 0 16px;
    font-size: 24px;
}

.pricing-card ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.pricing-card li {
    padding: 8px 0;
    font-size: 16px;
}

.pricing-hint {
    text-align: center;
    font-size: 14px;
    color: var(--text-secondary);
    margin-top: 16px;
}

/* ===== 信任背书区 ===== */
.trust {
    background: var(--card-bg);
}

.trust-cards {
    max-width: 1000px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    margin-bottom: 48px;
}

.trust-card {
    text-align: center;
    padding: 32px 24px;
    background: var(--light-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

[data-theme="dark"] .trust-card {
    background: #161B22;
}

.trust-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.trust-card h3 {
    margin: 0 0 12px;
    font-size: 20px;
}

.trust-card p {
    margin: 0;
    color: var(--text-secondary);
}

.trust-stats {
    max-width: 800px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    text-align: center;
}

.stat-item {
    padding: 24px;
}

.stat-number {
    font-size: 42px;
    font-weight: 700;
    color: var(--primary);
    display: block;
}

.stat-item p {
    margin: 8px 0 0;
    color: var(--text-secondary);
}

/* ===== 下载引导区 ===== */
.download-guide {
    background: var(--light-bg);
}

[data-theme="dark"] .download-guide {
    background: #0D1117;
}

.guide-steps {
    max-width: 1000px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.step-card {
    text-align: center;
    padding: 32px 24px;
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.step-number {
    width: 48px;
    height: 48px;
    line-height: 48px;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    font-size: 24px;
    font-weight: 700;
    margin: 0 auto 16px;
}

.step-card h3 {
    margin: 0 0 12px;
}

.step-card p {
    margin: 0 0 16px;
    color: var(--text-secondary);
}

/* ===== 新闻资讯区 ===== */
.news-section {
    background: var(--card-bg);
    padding: 80px 24px;
}

.section-desc {
    font-size: 16px;
    color: var(--text-secondary);
    margin: 8px 0 48px;
}

.news-grid-home {
    max-width: 1000px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.news-card-home {
    background: var(--light-bg);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.2s, box-shadow 0.2s;
}

[data-theme="dark"] .news-card-home {
    background: #161B22;
}

.news-card-home:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
}

.news-card-image {
    height: 120px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    display: flex;
    align-items: flex-end;
    padding: 12px;
}

.news-category-tag {
    background: rgba(255, 255, 255, 0.2);
    color: #fff;
    font-size: 12px;
    padding: 4px 10px;
    border-radius: 12px;
    backdrop-filter: blur(4px);
}

.news-card-body {
    padding: 20px;
}

.news-card-body h3 {
    font-size: 16px;
    margin: 0 0 8px;
    line-height: 1.4;
}

.news-card-body h3 a {
    color: var(--text-primary);
    text-decoration: none;
}

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

.news-card-body p {
    font-size: 13px;
    color: var(--text-secondary);
    margin: 0 0 12px;
    line-height: 1.5;
}

.news-meta {
    font-size: 12px;
    color: var(--text-secondary);
}

.news-more {
    text-align: center;
    margin-top: 32px;
}

/* ===== 博客列表页 ===== */
.news-list {
    padding: 80px 24px 80px;
    max-width: 1000px;
    margin: 0 auto;
}

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

.news-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.2s;
}

.news-card:hover {
    transform: translateY(-4px);
}

.news-card-body h3 {
    font-size: 18px;
    margin: 16px 16px 8px;
}

.news-card-body p {
    font-size: 14px;
    color: var(--text-secondary);
    margin: 0 16px 12px;
    line-height: 1.5;
}

.news-card-body .news-meta {
    margin: 0 16px 16px;
}

/* ===== 新闻详情页 ===== */
.news-detail {
    padding: 120px 24px 80px;
    max-width: 800px;
    margin: 0 auto;
}

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

.news-detail-header {
    margin-bottom: 32px;
    padding-bottom: 24px;
    border-bottom: 1px solid var(--border-color);
}

.news-category {
    background: var(--primary);
    color: #fff;
    font-size: 12px;
    padding: 4px 12px;
    border-radius: 12px;
}

.news-detail-header h1 {
    font-size: 28px;
    margin: 16px 0;
    color: var(--text-primary);
}

.news-detail-content {
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-primary);
}

.news-detail-footer {
    margin-top: 48px;
    padding-top: 24px;
    border-top: 1px solid var(--border-color);
}

/* ===== 分页 ===== */
.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 12px;
    margin-top: 40px;
}

.page-btn {
    display: inline-block;
    padding: 6px 12px;
    border-radius: 6px;
    background: var(--card-bg);
    color: var(--text-primary);
    text-decoration: none;
    font-size: 14px;
    border: 1px solid var(--border-color);
    transition: all 0.2s;
}

#pageNumbers .page-btn + .page-btn {
    margin-left: 8px;
}

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

.page-btn.active {
    background: var(--primary);
    color: #fff;
    border-color: var(--primary);
}

.pagination-info {
    text-align: center;
    font-size: 14px;
    color: var(--text-secondary);
    margin-top: 16px;
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .news-grid-home,
    .news-grid {
        grid-template-columns: 1fr;
    }

    .news-detail-inner {
        padding: 24px;
    }
}

/* ===== FAQ 区 ===== */
.faq {
    background: var(--card-bg);
}

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

.faq-item {
    padding: 24px;
    border-bottom: 1px solid var(--border-color);
}

.faq-item:last-child {
    border-bottom: none;
}

.faq-item h3 {
    margin: 0 0 12px;
    font-size: 18px;
    color: var(--text-primary);
}

.faq-item p {
    margin: 0;
    color: var(--text-secondary);
}

/* ===== 页脚 ===== */
.footer {
    background: var(--dark-bg);
    color: #9AACB8;
    padding: 32px 24px;
    text-align: center;
}

.footer-inner p {
    margin: 4px 0;
    font-size: 14px;
}

/* ===== 联系悬浮窗 ===== */
.contact-float {
    position: fixed;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    z-index: 999;
    background: var(--card-bg);
    border-radius: 12px 0 0 12px;
    box-shadow: -2px 4px 16px rgba(0, 0, 0, 0.15);
    padding: 12px;
    cursor: pointer;
    transition: transform 0.2s;
}

.contact-float:hover {
    transform: translateY(-50%) scale(1.05);
}

.contact-inner {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
}

.contact-qq-img {
    width: 80px;
    height: auto;
    border-radius: 4px;
}

.contact-label {
    font-size: 12px;
    font-weight: 600;
    color: var(--primary);
    margin: 0;
}

.contact-tip {
    font-size: 11px;
    color: var(--text-secondary);
    text-align: center;
    margin: 0;
    white-space: nowrap;
}

@media (max-width: 768px) {
    .contact-float {
        right: 0;
        top: auto;
        bottom: 20px;
        transform: none;
    }

    .contact-float:hover {
        transform: scale(1.05);
    }
}

/* ===== 模态框 ===== */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    z-index: 2000;
    align-items: center;
    justify-content: center;
}

.modal.show {
    display: flex;
}

.modal-content {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 32px;
    max-width: 500px;
    width: 90%;
    position: relative;
}

.modal-close {
    position: absolute;
    top: 12px;
    right: 16px;
    font-size: 28px;
    cursor: pointer;
    color: var(--text-secondary);
}

.modal-chat-bubble {
    background: var(--primary);
    color: #fff;
    padding: 16px 20px;
    border-radius: 16px 16px 16px 4px;
    font-size: 16px;
    min-height: 48px;
    margin-top: 16px;
}

/* ===== 滚动渐入动画 ===== */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* ===== 响应式 ===== */
@media (max-width: 768px) {
    .hero-inner,
    .ai-demo-inner,
    .trust-cards,
    .trust-stats,
    .guide-steps,
    .pricing-cards {
        grid-template-columns: 1fr;
    }

    .hero-title {
        font-size: 32px;
    }

    .navbar-links {
        display: none;
    }

    section {
        padding: 48px 16px;
    }
}