/* ===== 统一站点导航 — site-nav.css ===== */
/* 适用于 renxuai.com 全部页面的通用顶部导航栏 */

:root {
  --sn-bg: rgba(7, 17, 31, 0.96);
  --sn-text: #eef4ff;
  --sn-muted: #8a9ab8;
  --sn-active: #69a7ff;
  --sn-border: rgba(148, 163, 184, 0.14);
  --sn-hover-bg: rgba(105, 167, 255, 0.08);
  --sn-max: 1200px;
}

.site-nav {
  background: var(--sn-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--sn-border);
  position: sticky;
  top: 0;
  z-index: 1000;
  width: 100%;
}
.site-nav-inner {
  max-width: var(--sn-max);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 52px;
  gap: 16px;
}
.site-nav-logo {
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--sn-text);
  text-decoration: none;
  letter-spacing: -0.01em;
  white-space: nowrap;
  flex-shrink: 0;
}
.site-nav-logo:hover { color: var(--sn-active); }
.site-nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  list-style: none;
  margin: 0;
  padding: 0;
  flex-wrap: wrap;
  justify-content: flex-end;
}
.site-nav-links a {
  color: var(--sn-muted);
  text-decoration: none;
  font-size: 0.88rem;
  font-weight: 500;
  padding: 6px 14px;
  border-radius: 8px;
  transition: all 0.18s ease;
  white-space: nowrap;
}
.site-nav-links a:hover,
.site-nav-links a.active {
  color: var(--sn-text);
  background: var(--sn-hover-bg);
}
.site-nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--sn-muted);
  font-size: 1.4rem;
  cursor: pointer;
  padding: 4px 8px;
}

@media (max-width: 768px) {
  .site-nav-inner { height: auto; padding: 10px 16px; flex-wrap: wrap; }
  .site-nav-links { display: none; width: 100%; flex-direction: column; align-items: flex-start; gap: 2px; padding-top: 8px; }
  .site-nav-links.open { display: flex; }
  .site-nav-links a { width: 100%; padding: 10px 12px; }
  .site-nav-toggle { display: block; }
}

/* ---- 侧边栏导航 (有层级 section) ---- */
.section-layout {
  display: flex;
  max-width: var(--sn-max);
  margin: 0 auto;
  min-height: calc(100vh - 52px);
}
.section-sidebar {
  width: 220px;
  min-width: 220px;
  padding: 28px 20px;
  border-right: 1px solid var(--sn-border);
  position: sticky;
  top: 52px;
  height: calc(100vh - 52px);
  overflow-y: auto;
  background: rgba(7, 17, 31, 0.5);
}
.section-sidebar h3 {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--sn-muted);
  margin: 0 0 10px;
  font-weight: 600;
}
.section-sidebar a {
  display: block;
  color: var(--sn-muted);
  text-decoration: none;
  font-size: 0.85rem;
  padding: 6px 10px;
  border-radius: 6px;
  margin-bottom: 2px;
  transition: all 0.15s;
}
.section-sidebar a:hover,
.section-sidebar a.active {
  color: var(--sn-text);
  background: rgba(105, 167, 255, 0.1);
}
.section-main {
  flex: 1;
  min-width: 0;
  padding: 24px;
}

@media (max-width: 768px) {
  .section-layout { flex-direction: column; }
  .section-sidebar {
    width: 100%; min-width: 100%; height: auto;
    position: static; border-right: none;
    border-bottom: 1px solid var(--sn-border);
    padding: 16px 20px;
  }
  .section-sidebar a { display: inline-block; margin-right: 8px; }
}