/* 全局重置与基础 */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif; background: #f8faf9; color: #1e2a2f; line-height: 1.7; }
a { color: #1a6b3b; text-decoration: none; }
a:hover { text-decoration: underline; }
img, svg { display: block; max-width: 100%; height: auto; }
ul, ol { padding-left: 1.2rem; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 1.2rem; }

/* 导航吸顶 */
.navbar { position: sticky; top: 0; z-index: 1000; background: rgba(255,255,255,0.96); backdrop-filter: blur(6px); border-bottom: 1px solid #e2e8e4; transition: box-shadow 0.2s; }
.navbar.scrolled { box-shadow: 0 4px 20px rgba(0,0,0,0.06); }
.navbar .container { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.navbar .logo { font-size: 1.6rem; font-weight: 700; color: #1a6b3b; display: flex; align-items: center; gap: 0.4rem; }
.navbar .logo svg { width: 32px; height: 32px; }
.nav-links { display: flex; gap: 1.8rem; align-items: center; list-style: none; padding: 0; }
.nav-links a { font-size: 0.95rem; font-weight: 500; color: #2c3e3a; padding: 0.25rem 0; border-bottom: 2px solid transparent; transition: 0.2s; }
.nav-links a:hover, .nav-links a.active { color: #1a6b3b; border-bottom-color: #1a6b3b; text-decoration: none; }
.menu-toggle { display: none; background: none; border: none; font-size: 1.6rem; cursor: pointer; color: #1e2a2f; padding: 0.2rem; }

/* 移动菜单 */
.mobile-menu { display: none; background: #fff; border-top: 1px solid #e2e8e4; padding: 1rem 1.2rem; }
.mobile-menu.open { display: block; }
.mobile-menu a { display: block; padding: 0.6rem 0; font-size: 1rem; border-bottom: 1px solid #edf2ef; }

/* 面包屑 */
.breadcrumb { padding: 1rem 0 0.5rem; font-size: 0.85rem; color: #5a6e66; }
.breadcrumb a { color: #1a6b3b; }
.breadcrumb span { color: #7b8f86; }

/* 标题体系 */
h1 { font-size: 2.2rem; font-weight: 800; line-height: 1.25; margin-bottom: 0.8rem; color: #0f2b1f; }
h2 { font-size: 1.6rem; font-weight: 700; margin: 2.5rem 0 1rem; padding-bottom: 0.4rem; border-bottom: 3px solid #cfe6d8; color: #1a3d2c; }
h3 { font-size: 1.2rem; font-weight: 600; margin: 1.8rem 0 0.6rem; color: #25553b; }
h4 { font-size: 1.05rem; font-weight: 600; margin: 1.2rem 0 0.4rem; color: #2c6b47; }
p { margin-bottom: 1rem; }
section { margin-bottom: 2rem; }

/* 首屏特色 */
.hero { background: linear-gradient(135deg, #e6f3ed 0%, #cde8db 100%); border-radius: 20px; padding: 2.5rem 2rem; margin: 1.5rem 0 2rem; display: flex; flex-wrap: wrap; gap: 2rem; align-items: center; }
.hero-text { flex: 1 1 300px; }
.hero-text p { font-size: 1.1rem; color: #1f4030; }
.hero-visual { flex: 0 0 180px; text-align: center; }
.hero-visual svg { width: 160px; height: 160px; }
.btn { display: inline-block; background: #1a6b3b; color: #fff; padding: 0.6rem 1.6rem; border-radius: 30px; font-weight: 600; margin-top: 0.8rem; transition: 0.2s; border: none; cursor: pointer; }
.btn:hover { background: #0f522a; text-decoration: none; color: #fff; }

/* 栅格卡片 */
.grid-2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 1.5rem; margin: 1.2rem 0; }
.grid-3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 1.2rem; }
.card { background: #fff; border-radius: 16px; padding: 1.5rem; box-shadow: 0 2px 12px rgba(0,0,0,0.04); border: 1px solid #eef3f0; transition: 0.2s; }
.card:hover { box-shadow: 0 6px 24px rgba(0,0,0,0.08); }
.card-icon { margin-bottom: 0.8rem; }
.card-icon svg { width: 44px; height: 44px; }

/* FAQ */
.faq-item { border-bottom: 1px solid #e2e8e4; padding: 0.8rem 0; }
.faq-question { font-weight: 600; cursor: pointer; display: flex; justify-content: space-between; align-items: center; padding: 0.4rem 0; font-size: 1.05rem; }
.faq-question::after { content: '+'; font-size: 1.4rem; color: #1a6b3b; transition: 0.2s; }
.faq-item.open .faq-question::after { content: '−'; }
.faq-answer { max-height: 0; overflow: hidden; transition: max-height 0.35s ease, padding 0.25s; padding: 0 0.4rem; color: #2d4438; }
.faq-item.open .faq-answer { max-height: 600px; padding: 0.6rem 0.4rem 1rem; }

/* 文章列表 */
.article-list { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 1.5rem; margin: 1.2rem 0; }
.article-card { background: #fff; border-radius: 16px; padding: 1.2rem 1.5rem; border: 1px solid #eef3f0; transition: 0.2s; }
.article-card:hover { box-shadow: 0 4px 16px rgba(0,0,0,0.06); }
.article-card h4 { margin-top: 0; }
.article-meta { font-size: 0.8rem; color: #6d8579; margin-bottom: 0.4rem; }
.article-card p { font-size: 0.95rem; }
.read-more { display: inline-block; margin-top: 0.4rem; font-weight: 500; color: #1a6b3b; }
.read-more:hover { text-decoration: underline; }

/* 数字动画 */
.stats { display: flex; flex-wrap: wrap; gap: 2rem; justify-content: center; margin: 2rem 0; }
.stat-item { text-align: center; flex: 1 0 120px; }
.stat-number { font-size: 2.4rem; font-weight: 800; color: #1a6b3b; line-height: 1.2; }
.stat-label { font-size: 0.9rem; color: #4b6659; }

/* banner轮播 */
.carousel { position: relative; overflow: hidden; border-radius: 20px; background: #d9ebe2; min-height: 200px; margin: 1.5rem 0; }
.carousel-slide { display: flex; transition: transform 0.6s ease; }
.carousel-item { min-width: 100%; padding: 2rem; display: flex; align-items: center; justify-content: center; flex-direction: column; text-align: center; }
.carousel-item h3 { margin: 0 0 0.5rem; }
.carousel-controls { position: absolute; bottom: 12px; left: 50%; transform: translateX(-50%); display: flex; gap: 0.6rem; }
.carousel-dot { width: 10px; height: 10px; border-radius: 50%; background: #b3cdbf; border: none; cursor: pointer; transition: 0.2s; }
.carousel-dot.active { background: #1a6b3b; }
.carousel-dot:hover { background: #4a8f6a; }

/* 返回顶部 */
#back-to-top { position: fixed; bottom: 2rem; right: 2rem; width: 48px; height: 48px; border-radius: 50%; background: #1a6b3b; color: #fff; border: none; font-size: 1.6rem; cursor: pointer; opacity: 0; transform: translateY(20px); transition: 0.3s; box-shadow: 0 4px 12px rgba(0,0,0,0.15); display: flex; align-items: center; justify-content: center; z-index: 999; }
#back-to-top.visible { opacity: 1; transform: translateY(0); }
#back-to-top:hover { background: #0f522a; }

/* 暗黑模式 */
.dark-toggle { background: none; border: 1px solid #c0d4c8; border-radius: 30px; padding: 0.3rem 0.8rem; font-size: 0.9rem; cursor: pointer; color: #1e2a2f; transition: 0.2s; }
.dark-toggle:hover { background: rgba(26, 107, 59, 0.1); }
body.dark { background: #121c17; color: #dce6e0; }
body.dark .navbar { background: rgba(20,30,25,0.96); border-bottom-color: #2a3d33; }
body.dark .navbar .logo { color: #6fbf8a; }
body.dark .nav-links a { color: #b7cfc2; }
body.dark .card, body.dark .article-card { background: #1c2b23; border-color: #2a3d33; }
body.dark .hero { background: linear-gradient(135deg, #1c3328, #14261e); }
body.dark .breadcrumb a { color: #7fc99a; }
body.dark .faq-item { border-color: #2a3d33; }
body.dark .btn { background: #2b7a4b; }
body.dark .btn:hover { background: #1f5e38; }
body.dark .stat-number { color: #6fbf8a; }
body.dark .dark-toggle { border-color: #4b6659; color: #dce6e0; }
body.dark .carousel { background: #1a2b22; }
body.dark .carousel-dot { background: #2d4438; }
body.dark .carousel-dot.active { background: #4a9f6a; }
body.dark .mobile-menu { background: #1c2b23; }
body.dark .mobile-menu a { border-color: #2a3d33; color: #b7cfc2; }
body.dark .faq-question::after { color: #6fbf8a; }
body.dark h1 { color: #d4e8dd; }
body.dark h2 { color: #c0dcc8; border-bottom-color: #2a5a3f; }
body.dark h3 { color: #8fcba5; }
body.dark h4 { color: #7fc99a; }

/* 站内搜索 */
.search-box { display: flex; gap: 0.4rem; margin: 1rem 0; }
.search-box input { flex: 1; padding: 0.6rem 1rem; border: 1px solid #d0dfd6; border-radius: 30px; font-size: 0.95rem; background: #fff; transition: 0.2s; }
.search-box input:focus { outline: none; border-color: #1a6b3b; box-shadow: 0 0 0 2px rgba(26, 107, 59, 0.2); }
.search-box button { padding: 0.6rem 1.2rem; border-radius: 30px; border: none; background: #1a6b3b; color: #fff; font-weight: 600; cursor: pointer; transition: 0.2s; }
.search-box button:hover { background: #0f522a; }
body.dark .search-box input { background: #1f3028; border-color: #2a3d33; color: #dce6e0; }
body.dark .search-box input:focus { border-color: #6fbf8a; box-shadow: 0 0 0 2px rgba(111, 191, 138, 0.2); }

/* 页脚 */
.footer { background: #17241e; color: #b0c7bb; padding: 2.5rem 0 1.5rem; margin-top: 3rem; border-radius: 24px 24px 0 0; }
.footer a { color: #8fcba5; transition: 0.2s; }
.footer a:hover { color: #b0e0c0; text-decoration: underline; }
.footer-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 1.5rem; }
.footer h4 { color: #d4e8dd; margin-bottom: 0.8rem; }
.footer ul { list-style: none; padding: 0; }
.footer li { margin-bottom: 0.3rem; font-size: 0.9rem; }
.footer-bottom { border-top: 1px solid #2e4238; margin-top: 1.5rem; padding-top: 1rem; text-align: center; font-size: 0.85rem; }

/* 响应式 */
@media (max-width: 768px) {
    .nav-links { display: none; }
    .menu-toggle { display: block; }
    h1 { font-size: 1.6rem; }
    .hero { flex-direction: column; padding: 1.5rem; }
    .hero-visual { flex-basis: auto; }
    .stats { gap: 1rem; }
    .footer-grid { grid-template-columns: repeat(2, 1fr); }
    .carousel-item h3 { font-size: 1.1rem; }
    .carousel-item p { font-size: 0.9rem; }
}

@media (max-width: 480px) {
    .grid-2, .grid-3, .article-list { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; }
    .hero { padding: 1.2rem; }
    .hero-text p { font-size: 1rem; }
    .stat-number { font-size: 2rem; }
    #back-to-top { width: 40px; height: 40px; font-size: 1.3rem; bottom: 1.5rem; right: 1.5rem; }
}

/* 滚动动画初始 */
.fade-up { opacity: 0; transform: translateY(24px); transition: opacity 0.7s ease, transform 0.7s ease; }
.fade-up.visible { opacity: 1; transform: translateY(0); }

/* 图片懒加载辅助 */
.lazy-svg { background: #eef3f0; border-radius: 8px; }
body.dark .lazy-svg { background: #1f3028; }