/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background-color: #ffffff;
    color: #1e1e1e;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

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

/* 导航 */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
    border-bottom: 1px solid #f0f0f0;
    flex-wrap: wrap;
}

.logo a {
    font-size: 1.8rem;
    font-weight: 700;
    letter-spacing: -0.5px;
    text-decoration: none;
    color: #1e1e1e;
}

.logo span {
    color: #2563eb;
}

.nav-links {
    display: flex;
    gap: 30px;
    align-items: center;
    flex-wrap: wrap;
}

.nav-links a {
    text-decoration: none;
    color: #4b4b4b;
    font-weight: 500;
    transition: color 0.2s;
}

.nav-links a:hover {
    color: #2563eb;
}

.nav-links .social-icons a {
    margin-left: 12px;
    color: #6b6b6b;
    font-size: 1.2rem;
}

/* 页脚 */
.footer {
    border-top: 1px solid #f0f0f0;
    padding: 48px 0 32px;
    margin-top: 60px;
    color: #6b6b6b;
    font-size: 0.9rem;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    margin-bottom: 40px;
}

.footer-col h5 {
    margin-bottom: 16px;
    color: #2d2d2d;
}

.footer-links {
    list-style: none;
}

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

.footer-links a {
    text-decoration: none;
    color: #6b6b6b;
    transition: color 0.2s;
}

.footer-links a:hover {
    color: #2563eb;
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 32px;
    border-top: 1px solid #f0f0f0;
}

/* 通用标题 */
.section-title {
    font-size: 2.2rem;
    font-weight: 700;
    letter-spacing: -0.5px;
    margin: 40px 0 24px;
}

.section-sub {
    color: #6b6b6b;
    max-width: 600px;
    margin-bottom: 40px;
}

/* 按钮 */
.btn {
    display: inline-block;
    background-color: #2563eb;
    color: white;
    font-weight: 600;
    padding: 12px 32px;
    border-radius: 40px;
    text-decoration: none;
    transition: background-color 0.2s;
}

.btn:hover {
    background-color: #1d4ed8;
}

/* 产品网格（复用） */
.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 30px;
    margin: 40px 0;
}

.product-card {
    background: white;
    border-radius: 20px;
    padding: 24px;
    box-shadow: 0 8px 30px rgba(0,0,0,0.02);
    border: 1px solid #f0f0f0;
    transition: all 0.25s;
}

.product-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 20px 40px rgba(0,0,0,0.06);
}

.product-icon {
    width: 52px;
    height: 52px;
    background: #f0f4ff;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #2563eb;
    font-size: 1.8rem;
    margin-bottom: 18px;
}

.product-title {
    font-size: 1.4rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.product-desc {
    color: #5f5f5f;
    font-size: 0.95rem;
    margin-bottom: 20px;
    flex: 1;
}

.product-meta {
    display: flex;
    gap: 8px;
    margin-bottom: 18px;
    flex-wrap: wrap;
}

.badge {
    background: #f0f0f0;
    border-radius: 30px;
    padding: 4px 12px;
    font-size: 0.75rem;
    font-weight: 500;
    color: #4b4b4b;
}

.badge.blue {
    background: #e6f0ff;
    color: #2563eb;
}

.download-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-top: 1px solid #f0f0f0;
    padding-top: 16px;
}

.download-count {
    color: #8a8a8a;
    font-size: 0.85rem;
}

.download-count i {
    margin-right: 4px;
    color: #2563eb;
}

.download-btn {
    background: none;
    border: 1px solid #d0d0d0;
    border-radius: 30px;
    padding: 8px 22px;
    font-weight: 500;
    color: #1e1e1e;
    text-decoration: none;
    transition: all 0.2s;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.download-btn:hover {
    background: #2563eb;
    border-color: #2563eb;
    color: white;
}

/* 博客卡片 */
.blog-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
    margin: 40px 0;
}

.blog-card {
    background: white;
    border-radius: 20px;
    overflow: hidden;
    border: 1px solid #f0f0f0;
    transition: all 0.25s;
}

.blog-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.05);
}

.blog-image {
    width: 100%;
    height: 180px;
    object-fit: cover;
}

.blog-content {
    padding: 20px;
}

.blog-date {
    color: #2563eb;
    font-size: 0.85rem;
    margin-bottom: 8px;
}

.blog-title {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 10px;
}

.blog-summary {
    color: #5f5f5f;
    font-size: 0.9rem;
    margin-bottom: 16px;
}

.read-more {
    color: #2563eb;
    text-decoration: none;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

/* 响应式 */
@media (max-width: 900px) {
    .navbar {
        flex-direction: column;
        gap: 16px;
    }
    .nav-links {
        justify-content: center;
    }
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 600px) {
    .footer-grid {
        grid-template-columns: 1fr;
    }
    .footer-bottom {
        flex-direction: column;
        gap: 16px;
        text-align: center;
    }
}