/* ============================================================
   跨境导航 · 现代 SaaS 风样式
   靛蓝主色 + 圆角卡片 + 留白 + 响应式
   ============================================================ */

/* ---- 设计令牌（CSS Variables）---- */
:root {
  /* 主色系 - 靛蓝 */
  --color-primary: #4f46e5;
  --color-primary-dark: #4338ca;
  --color-primary-light: #6366f1;
  --color-primary-bg: #eef2ff;
  --color-primary-bg-hover: #e0e7ff;

  /* 中性色 */
  --color-bg: #f8fafc;
  --color-bg-alt: #f1f5f9;
  --color-surface: #ffffff;
  --color-border: #e2e8f0;
  --color-border-light: #f1f5f9;

  /* 文字色 */
  --color-text: #0f172a;
  --color-text-secondary: #475569;
  --color-text-muted: #94a3b8;

  /* 标签色 */
  --color-tag-featured: #4f46e5;
  --color-tag-free: #059669;
  --color-tag-overseas: #d97706;
  --color-tag-shopify: #10b981;
  --color-tag-china: #dc2626;
  --color-tag-saas: #7c3aed;

  /* 阴影 */
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.04);
  --shadow-md: 0 4px 6px -1px rgba(15, 23, 42, 0.07), 0 2px 4px -2px rgba(15, 23, 42, 0.05);
  --shadow-lg: 0 10px 15px -3px rgba(15, 23, 42, 0.08), 0 4px 6px -4px rgba(15, 23, 42, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(15, 23, 42, 0.1), 0 8px 10px -6px rgba(15, 23, 42, 0.06);

  /* 圆角 */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --radius-xl: 20px;
  --radius-full: 9999px;

  /* 间距 */
  --space-page: 32px;
  --container-max: 1200px;

  /* 过渡 */
  --transition: 0.18s cubic-bezier(0.4, 0, 0.2, 1);

  /* 字体 */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial,
    sans-serif;
}

/* ---- 基础重置 ---- */
*, *::before, *::after { box-sizing: border-box; }
* { margin: 0; padding: 0; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.65;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

img, svg { max-width: 100%; display: block; }
a { color: var(--color-primary); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--color-primary-dark); }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
ul { list-style: none; }

h1, h2, h3, h4 { line-height: 1.3; font-weight: 700; color: var(--color-text); }

.container { max-width: var(--container-max); margin: 0 auto; padding: 0 24px; width: 100%; }

/* ---- 站点头部 ---- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--color-border);
}
.header-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px;
}
.brand { display: flex; align-items: center; gap: 10px; color: var(--color-text); font-weight: 700; font-size: 18px; }
.brand:hover { color: var(--color-primary); }
.brand-icon { font-size: 24px; }
.main-nav ul { display: flex; gap: 4px; }
.main-nav a {
  display: block; padding: 8px 14px; border-radius: var(--radius-md);
  color: var(--color-text-secondary); font-size: 14px; font-weight: 500;
}
.main-nav a:hover { background: var(--color-bg-alt); color: var(--color-text); }
.main-nav a.active { color: var(--color-primary); background: var(--color-primary-bg); }

.nav-toggle { display: none; flex-direction: column; gap: 5px; padding: 8px; }
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--color-text); border-radius: 2px; transition: var(--transition); }

/* ---- Hero 区 ---- */
.hero {
  padding: 72px 0 48px;
  background:
    radial-gradient(ellipse 80% 60% at 50% 0%, var(--color-primary-bg) 0%, transparent 70%);
  text-align: center;
}
.hero-sm { padding: 40px 0 32px; }
.hero-title {
  font-size: 48px; font-weight: 800; letter-spacing: -0.02em;
  background: linear-gradient(135deg, var(--color-text) 0%, var(--color-primary) 100%);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero-title-sm { font-size: 36px; display: flex; align-items: center; justify-content: center; gap: 14px; }
.hero-title-accent { color: var(--color-primary); -webkit-text-fill-color: var(--color-primary); }
.hero-subtitle { font-size: 20px; color: var(--color-text-secondary); margin-top: 12px; font-weight: 500; }
.hero-desc { max-width: 640px; margin: 16px auto 0; color: var(--color-text-muted); font-size: 15px; }
.hero-stats {
  margin-top: 24px; display: flex; align-items: center; justify-content: center;
  gap: 12px; flex-wrap: wrap; color: var(--color-text-secondary); font-size: 14px;
}
.hero-stats strong { color: var(--color-primary); font-weight: 700; }
.hero-stats .sep { color: var(--color-border); }

/* ---- 搜索区 ---- */
.search-section { margin: -8px 0 40px; }
.search-box {
  position: relative; max-width: 640px; margin: 0 auto;
  display: flex; align-items: center;
  background: var(--color-surface); border: 1px solid var(--color-border);
  border-radius: var(--radius-full); padding: 4px 4px 4px 18px;
  box-shadow: var(--shadow-lg); transition: var(--transition);
}
.search-box:focus-within { border-color: var(--color-primary); box-shadow: 0 0 0 4px var(--color-primary-bg); }
.search-icon { display: flex; color: var(--color-text-muted); }
.search-input {
  flex: 1; border: none; outline: none; background: transparent;
  font-size: 16px; padding: 14px 12px; color: var(--color-text);
}
.search-input::placeholder { color: var(--color-text-muted); }
.search-clear {
  width: 36px; height: 36px; border-radius: var(--radius-full);
  font-size: 24px; color: var(--color-text-muted); display: flex; align-items: center; justify-content: center;
  transition: var(--transition);
}
.search-clear:hover { background: var(--color-bg-alt); color: var(--color-text); }

.filter-tags {
  max-width: 640px; margin: 20px auto 0;
  display: flex; align-items: center; flex-wrap: wrap; gap: 8px; justify-content: center;
}
.filter-label { color: var(--color-text-muted); font-size: 13px; }
.filter-chip {
  padding: 6px 14px; border-radius: var(--radius-full); font-size: 13px; font-weight: 500;
  background: var(--color-surface); border: 1px solid var(--color-border);
  color: var(--color-text-secondary); transition: var(--transition);
}
.filter-chip:hover { border-color: var(--color-primary); color: var(--color-primary); }
.filter-chip.active {
  background: var(--color-primary); border-color: var(--color-primary); color: #fff;
}
.search-stats { text-align: center; margin-top: 14px; color: var(--color-text-muted); font-size: 13px; }

/* ---- 主内容 ---- */
.main-content { padding-bottom: 64px; }

/* ---- 运营指南区块（首页文章预览）---- */
.blog-section { padding: 0 0 40px; }
.blog-section-head {
  display: flex; align-items: center; justify-content: space-between; margin-bottom: 20px;
}
.section-title { font-size: 22px; font-weight: 700; }
.blog-section-more {
  font-size: 14px; font-weight: 500; color: var(--color-primary);
}
.blog-section-more:hover { text-decoration: underline; }
.blog-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 16px;
}
.blog-card {
  background: var(--color-surface); border: 1px solid var(--color-border);
  border-radius: var(--radius-lg); transition: var(--transition); overflow: hidden;
}
.blog-card:hover { border-color: var(--color-primary-light); box-shadow: var(--shadow-md); transform: translateY(-2px); }
.blog-card-link { display: block; padding: 20px; color: inherit; }
.blog-card-link:hover { color: inherit; }
.blog-card-title { font-size: 16px; font-weight: 600; margin-bottom: 8px; color: var(--color-text); }
.blog-card-date { font-size: 12px; color: var(--color-text-muted); display: block; margin-bottom: 8px; }
.blog-card-excerpt { font-size: 13px; color: var(--color-text-secondary); line-height: 1.5; }

/* ---- 分类区块 ---- */
.category-section { margin-bottom: 56px; }
.category-head { margin-bottom: 20px; }
.category-title {
  font-size: 22px; display: flex; align-items: center; gap: 10px; font-weight: 700;
}
.category-title a { color: inherit; }
.category-title a:hover { color: var(--color-primary); }
.category-icon { font-size: 26px; }
.category-count {
  font-size: 13px; font-weight: 600; color: var(--color-primary);
  background: var(--color-primary-bg); padding: 2px 10px; border-radius: var(--radius-full);
}
.category-desc { color: var(--color-text-muted); margin-top: 8px; font-size: 14px; max-width: 720px; }

/* ---- 站点卡片网格 ---- */
.sites-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
}

.site-card {
  background: var(--color-surface); border: 1px solid var(--color-border);
  border-radius: var(--radius-lg); box-shadow: var(--shadow-sm);
  transition: var(--transition); overflow: hidden; position: relative;
}
.site-card:hover {
  transform: translateY(-2px); box-shadow: var(--shadow-lg); border-color: var(--color-primary-light);
}
.site-card.is-featured { border-color: var(--color-primary-bg-hover); }
.site-card.is-featured::before {
  content: ""; position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-primary-light));
}
.site-card-link { display: block; padding: 18px; color: inherit; }
.site-card-link:hover { color: inherit; }

.site-card-head { display: flex; align-items: center; gap: 12px; margin-bottom: 10px; }
.site-card-favicon {
  width: 36px; height: 36px; border-radius: var(--radius-md);
  background: var(--color-bg-alt); flex-shrink: 0;
}
.site-card-titles { flex: 1; min-width: 0; }
.site-card-name {
  font-size: 15px; font-weight: 600; color: var(--color-text);
  display: flex; align-items: center; gap: 4px;
}
.site-card-name .star { color: #f59e0b; font-size: 13px; }
.site-card-domain {
  font-size: 12px; color: var(--color-text-muted); display: block;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.site-card-desc {
  color: var(--color-text-secondary); font-size: 13px; line-height: 1.55;
  display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
}
.site-card-tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 12px; }

/* ---- 标签 ---- */
.tag {
  display: inline-block; padding: 2px 8px; border-radius: var(--radius-sm);
  font-size: 11px; font-weight: 600; letter-spacing: 0.02em;
}
/* 领域专属标签配色（跨境导航遗留，保留兼容） */
.tag-featured { background: var(--color-primary-bg); color: var(--color-tag-featured); }
.tag-free { background: #d1fae5; color: var(--color-tag-free); }
.tag-overseas-entity { background: #fef3c7; color: var(--color-tag-overseas); }
.tag-shopify-app { background: #d1fae5; color: var(--color-tag-shopify); }
.tag-china-team { background: #fee2e2; color: var(--color-tag-china); }
.tag-saas { background: #ede9fe; color: var(--color-tag-saas); }
.tag-default { background: var(--color-bg-alt); color: var(--color-text-secondary); }

/* 通用兜底：未定义专属配色的标签（任意领域的自定义标签）走中性灰 */
[class^="tag-"]:not(.tag-featured):not(.tag-free):not(.tag-overseas-entity):not(.tag-shopify-app):not(.tag-china-team):not(.tag-saas):not(.tag-default) {
  background: var(--color-bg-alt); color: var(--color-text-secondary);
}

/* ---- 卡片筛选隐藏（JS 控制）---- */
.site-card.is-hidden, .category-section.is-hidden { display: none; }

/* ---- 无结果 ---- */
.no-results { text-align: center; padding: 64px 24px; color: var(--color-text-muted); }
.no-results-icon { font-size: 48px; margin-bottom: 16px; }
.no-results p { font-size: 16px; }
.no-results-hint { font-size: 13px; margin-top: 8px; }

/* ---- 面包屑 ---- */
.breadcrumb {
  font-size: 13px; color: var(--color-text-muted);
  display: flex; align-items: center; gap: 8px; flex-wrap: wrap; margin-bottom: 20px;
}
.breadcrumb .sep { color: var(--color-border); }
.breadcrumb .current { color: var(--color-text-secondary); }

/* ---- 分类页 ---- */
.category-nav { margin-bottom: 24px; }
.back-link {
  display: inline-flex; align-items: center; gap: 4px;
  color: var(--color-text-muted); font-size: 14px; font-weight: 500;
}
.back-link:hover { color: var(--color-primary); }

/* ---- 文章列表 ---- */
.post-list { display: flex; flex-direction: column; gap: 16px; max-width: 760px; margin: 0 auto; }
.post-card {
  background: var(--color-surface); border: 1px solid var(--color-border);
  border-radius: var(--radius-lg); padding: 24px;
  transition: var(--transition);
}
.post-card:hover { border-color: var(--color-primary-light); box-shadow: var(--shadow-md); }
.post-card-link { color: inherit; display: block; }
.post-card-link:hover { color: inherit; }
.post-card-meta { font-size: 13px; color: var(--color-text-muted); margin-bottom: 10px; }
.post-card-meta .sep { margin: 0 6px; }
.post-card-title { font-size: 20px; margin-bottom: 8px; }
.post-card-title:hover { color: var(--color-primary); }
.post-card-excerpt { color: var(--color-text-secondary); font-size: 14px; }
.post-card-tags { display: flex; gap: 6px; margin-top: 12px; }
.empty-state { text-align: center; padding: 64px; color: var(--color-text-muted); }

/* ---- 分页 ---- */
.pagination {
  display: flex; align-items: center; justify-content: center; gap: 16px;
  margin-top: 48px; padding: 24px 0;
}
.page-link {
  padding: 8px 16px; border-radius: var(--radius-md); font-size: 14px; font-weight: 500;
  background: var(--color-surface); border: 1px solid var(--color-border); color: var(--color-text);
  transition: var(--transition);
}
.page-link:not(.disabled):hover { border-color: var(--color-primary); color: var(--color-primary); }
.page-link.disabled { color: var(--color-text-muted); cursor: not-allowed; opacity: 0.5; }
.page-info { color: var(--color-text-muted); font-size: 14px; }

/* ---- 文章详情 ---- */
.post { max-width: 760px; }
.post-header { margin: 32px 0; padding-bottom: 24px; border-bottom: 1px solid var(--color-border); }
.post-title { font-size: 34px; font-weight: 800; letter-spacing: -0.02em; margin-bottom: 12px; }
.post-subtitle { font-size: 18px; color: var(--color-text-secondary); }
.post-meta { font-size: 14px; color: var(--color-text-muted); display: flex; align-items: center; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.post-meta .sep { color: var(--color-border); }
.post-tags { display: flex; gap: 6px; margin-left: auto; }
.post-content { font-size: 16px; line-height: 1.8; color: var(--color-text); }
.post-content h2 { font-size: 26px; margin: 40px 0 16px; }
.post-content h3 { font-size: 20px; margin: 32px 0 12px; }
.post-content p { margin: 16px 0; }
.post-content ul, .post-content ol { margin: 16px 0; padding-left: 24px; }
.post-content li { margin: 6px 0; }
.post-content ul { list-style: disc; }
.post-content ol { list-style: decimal; }
.post-content blockquote {
  border-left: 4px solid var(--color-primary); background: var(--color-primary-bg);
  padding: 12px 20px; margin: 20px 0; border-radius: 0 var(--radius-md) var(--radius-md) 0;
  color: var(--color-text-secondary);
}
.post-content code {
  background: var(--color-bg-alt); padding: 2px 6px; border-radius: var(--radius-sm);
  font-size: 0.9em; font-family: "SF Mono", Monaco, Consolas, monospace;
}
.post-content pre {
  background: #1e293b; color: #e2e8f0; padding: 20px; border-radius: var(--radius-md);
  overflow-x: auto; margin: 20px 0;
}
.post-content pre code { background: none; padding: 0; color: inherit; }
.post-content img { border-radius: var(--radius-md); margin: 20px 0; }
.post-content a { text-decoration: underline; text-underline-offset: 2px; }
.post-content table { width: 100%; border-collapse: collapse; margin: 20px 0; }
.post-content th, .post-content td { border: 1px solid var(--color-border); padding: 10px 14px; text-align: left; }
.post-content th { background: var(--color-bg-alt); font-weight: 600; }
.post-footer { margin-top: 48px; padding-top: 24px; border-top: 1px solid var(--color-border); }

/* ---- 通用单页（关于/隐私等）---- */
.page { max-width: 760px; }
.page-header { margin: 32px 0; padding-bottom: 24px; border-bottom: 1px solid var(--color-border); }
.page-title { font-size: 34px; font-weight: 800; letter-spacing: -0.02em; }
.page-subtitle { font-size: 18px; color: var(--color-text-secondary); margin-top: 8px; }
.page-content { font-size: 16px; line-height: 1.8; color: var(--color-text); }
.page-content h2 { font-size: 22px; margin: 36px 0 14px; }
.page-content p { margin: 14px 0; }
.page-content ul { margin: 14px 0; padding-left: 24px; list-style: disc; }
.page-content li { margin: 6px 0; }

/* ---- 页脚 ---- */
.site-footer {
  background: var(--color-surface); border-top: 1px solid var(--color-border);
  margin-top: 64px; padding: 48px 0 0;
}
.footer-inner {
  display: grid; grid-template-columns: 1.5fr 2fr; gap: 48px; padding-bottom: 40px;
}
.footer-brand .brand { margin-bottom: 12px; }
.footer-tagline { color: var(--color-text-muted); font-size: 14px; max-width: 320px; }
.footer-nav { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }
.footer-col h4 { font-size: 13px; font-weight: 600; color: var(--color-text-muted); text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: 14px; }
.footer-col ul { display: flex; flex-direction: column; gap: 10px; }
.footer-col a { color: var(--color-text-secondary); font-size: 14px; }
.footer-col a:hover { color: var(--color-primary); }
.footer-bottom {
  border-top: 1px solid var(--color-border-light); padding: 24px 0;
  text-align: center; color: var(--color-text-muted); font-size: 13px;
}
.footer-bottom p { margin: 4px 0; }
.footer-disclaimer { font-size: 12px; opacity: 0.8; }

/* ---- 响应式 ---- */
@media (max-width: 900px) {
  .footer-inner { grid-template-columns: 1fr; gap: 32px; }
  .footer-nav { grid-template-columns: repeat(3, 1fr); }
}

/* ---- 移动端底部导航栏 ---- */
.mobile-bottom-nav {
  display: none;
  position: fixed; bottom: 0; left: 0; right: 0; z-index: 99;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-top: 1px solid var(--color-border);
  padding: 6px 8px env(safe-area-inset-bottom, 6px);
}
.mobile-bottom-nav-inner {
  display: flex; align-items: center; justify-content: space-around;
  max-width: 480px; margin: 0 auto;
}
.mbn-item {
  display: flex; flex-direction: column; align-items: center; gap: 2px;
  padding: 4px 12px; border-radius: var(--radius-md);
  color: var(--color-text-muted); font-size: 11px; font-weight: 500;
  transition: var(--transition); min-width: 56px; text-align: center;
}
.mbn-item:hover, .mbn-item.active { color: var(--color-primary); }
.mbn-icon { font-size: 20px; line-height: 1; }

@media (max-width: 768px) {
  .mobile-bottom-nav { display: block; }
  /* 给页面底部留出空间避免被底栏遮挡 */
  .site-footer { padding-bottom: calc(48px + env(safe-area-inset-bottom, 0px)); margin-bottom: 64px; }
  .container { padding: 0 16px; }
  .hero { padding: 48px 0 32px; }
  .hero-title { font-size: 36px; }
  .hero-title-sm { font-size: 28px; }
  .hero-subtitle { font-size: 17px; }
  .hero-stats { font-size: 13px; }

  /* 移动端汉堡菜单 */
  .nav-toggle { display: flex; }
  .main-nav {
    position: fixed; top: 64px; left: 0; right: 0; bottom: 0;
    background: var(--color-surface); padding: 16px;
    flex-direction: column; transform: translateX(100%);
    transition: transform var(--transition); border-top: 1px solid var(--color-border);
  }
  .main-nav.open { transform: translateX(0); }
  .main-nav ul { flex-direction: column; gap: 4px; }
  .main-nav a { padding: 14px; font-size: 16px; }
  body.nav-open { overflow: hidden; }

  .sites-grid { grid-template-columns: 1fr; }
  .category-title { font-size: 19px; }
  .post-title, .page-title { font-size: 26px; }
  .search-box { padding-left: 14px; }
  .search-input { padding: 12px 8px; font-size: 15px; }
  .filter-tags { justify-content: flex-start; overflow-x: auto; flex-wrap: nowrap; padding-bottom: 4px; -webkit-overflow-scrolling: touch; }
  .filter-label { flex-shrink: 0; }
  .filter-chip { flex-shrink: 0; }
  .footer-nav { grid-template-columns: 1fr; gap: 24px; }

  /* 移动端博客区块 */
  .blog-grid { grid-template-columns: 1fr; }
  .blog-section-head { flex-direction: column; align-items: flex-start; gap: 8px; }
}

@media (max-width: 480px) {
  .hero-title { font-size: 30px; }
  .hero-stats { gap: 8px; }
  .hero-stats .sep { display: none; }
}

/* ---- 可访问性 ---- */
:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 2px; border-radius: var(--radius-sm); }
@media (prefers-reduced-motion: reduce) {
  * { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; scroll-behavior: auto !important; }
}

/* ---- 选择文本配色 ---- */
::selection { background: var(--color-primary-bg); color: var(--color-primary-dark); }