/* ===== Main Layout ===== */
.main-container {
  max-width: 1200px; margin: 0 auto; padding: 0 20px 60px;
  display: grid; grid-template-columns: 1fr 320px; gap: 24px; align-items: start;
}

/* ===== CSS-only Article Switching ===== */
.news-detail { display: none; }
.news-detail:target { display: block; }
/* 当没有任何 article 被 target 时，显示第一个 */
.articles-wrap:not(:has(.news-detail:target)) .news-detail:first-child { display: block; }

/* ===== Article Card ===== */
.article-card { background: #FFF; border-radius: 12px; box-shadow: 0 2px 12px rgba(0,0,0,0.06); overflow: hidden; }
.article-banner {
  height: 220px;
  background: linear-gradient(135deg, #FFF3E0 0%, #FFE0B2 50%, #FFCC80 100%);
  display: flex; align-items: center; justify-content: center; position: relative;
}
.article-banner-icon { font-size: 72px; opacity: 0.4; }
.article-category {
  position: absolute; top: 16px; left: 16px; background: #F57C00; color: #FFF;
  padding: 5px 16px; border-radius: 16px; font-size: 13px; font-weight: 600;
}
.article-body { padding: 32px; }
.article-title { font-size: 24px; font-weight: 700; color: #37474F; line-height: 1.5; margin-bottom: 16px; }
.article-meta {
  display: flex; align-items: center; gap: 20px; padding-bottom: 20px; margin-bottom: 24px;
  border-bottom: 1px solid #ECEFF1; font-size: 13px; color: #78909C; flex-wrap: wrap;
}
.article-meta-item { display: flex; align-items: center; gap: 5px; }
.article-content { font-size: 15px; line-height: 1.9; color: #455A64; }
.article-content p { margin-bottom: 16px; text-align: justify; }
.article-content strong { color: #37474F; font-weight: 700; }
.article-tags { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 28px; padding-top: 20px; border-top: 1px solid #ECEFF1; }
.article-tag { padding: 4px 14px; background: #FFF3E0; border-radius: 14px; font-size: 12px; color: #F57C00; font-weight: 500; }

/* ===== Article Nav ===== */
.article-nav { display: flex; justify-content: space-between; margin-top: 24px; padding-top: 20px; border-top: 1px solid #ECEFF1; gap: 16px; }
.article-nav-btn {
  display: flex; align-items: center; gap: 8px; padding: 10px 20px;
  background: #FFF; border: 2px solid #ECEFF1; border-radius: 8px;
  font-size: 13px; color: #78909C; transition: all 0.2s; text-decoration: none; max-width: 48%;
}
.article-nav-btn:hover { border-color: #F57C00; color: #F57C00; }
.nav-label { font-size: 11px; color: #B0BEC5; display: block; }
.nav-title { font-weight: 600; display: -webkit-box; -webkit-line-clamp: 1; -webkit-box-orient: vertical; overflow: hidden; }

/* ===== Sidebar ===== */
.sidebar { position: sticky; top: 90px; }
.sidebar-card { background: #FFF; border-radius: 12px; box-shadow: 0 2px 12px rgba(0,0,0,0.06); overflow: hidden; margin-bottom: 20px; }
.sidebar-header { padding: 16px 20px; border-bottom: 1px solid #ECEFF1; font-size: 16px; font-weight: 700; color: #37474F; display: flex; align-items: center; gap: 8px; }
.sidebar-body { padding: 16px 20px; }
.sidebar-news-item { display: block; padding: 12px 0; border-bottom: 1px solid #F5F5F5; text-decoration: none; color: inherit; transition: color 0.2s; }
.sidebar-news-item:last-child { border-bottom: none; }
.sidebar-news-item:hover { color: #F57C00; }
.sidebar-news-title { font-size: 14px; font-weight: 500; color: #37474F; line-height: 1.5; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.sidebar-news-item:hover .sidebar-news-title { color: #F57C00; }
.sidebar-news-date { font-size: 12px; color: #B0BEC5; margin-top: 4px; }

/* ===== Calc Widget ===== */
.calc-widget { background: linear-gradient(135deg, #FFF3E0 0%, #FFE0B2 100%); border-radius: 12px; padding: 24px; text-align: center; margin-bottom: 20px; }
.calc-widget-icon { font-size: 36px; margin-bottom: 12px; }
.calc-widget-title { font-size: 16px; font-weight: 700; color: #37474F; margin-bottom: 8px; }
.calc-widget-desc { font-size: 13px; color: #78909C; margin-bottom: 16px; line-height: 1.5; }
.calc-widget-btn { display: inline-block; padding: 10px 28px; background: #F57C00; color: #FFF; border-radius: 8px; font-size: 14px; font-weight: 600; transition: all 0.2s; text-decoration: none; }
.calc-widget-btn:hover { background: #E65100; color: #FFF; transform: translateY(-1px); }

/* ===== Responsive (Show) ===== */
@media (max-width: 768px) {
  .main-container { grid-template-columns: 1fr; }
  .sidebar { position: static; }
  .article-body { padding: 20px; }
  .article-title { font-size: 20px; }
  .article-banner { height: 160px; }
  .article-nav { flex-direction: column; }
  .article-nav-btn { max-width: 100%; }
}