/* =========================================================
   layout.css —— 容器、头部、栅格、页脚、响应式断点
   断点：360px（默认移动优先）/ 768px / 1024px / 1440px
   ========================================================= */

.container {
  width: 100%;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 16px;
}

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  background: color-mix(in srgb, var(--bg-card) 92%, transparent);
  -webkit-backdrop-filter: saturate(180%) blur(10px);
  backdrop-filter: saturate(180%) blur(10px);
  border-bottom: 1px solid var(--line);
}

.site-header .container {
  height: 100%;
  display: flex;
  align-items: center;
  gap: 14px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 1.05rem;
  white-space: nowrap;
}

.brand .brand-mark {
  width: 28px;
  height: 28px;
  color: var(--brand);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 2px;
}

.main-nav a {
  display: inline-flex;
  align-items: center;
  padding: 8px 12px;
  border-radius: var(--radius-s);
  font-size: .95rem;
  color: var(--text-2);
}

.main-nav a:hover { background: var(--bg-soft); color: var(--text); }
.main-nav a.active { color: var(--brand); font-weight: 600; }

.header-right {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 8px;
}

/* 桌面端顶部搜索框 */
.header-search {
  position: relative;
  width: min(280px, 24vw);
}

/* ---------- 主体布局 ---------- */
.layout-main {
  display: flex;
  gap: 24px;
  padding: 20px 0 96px;
}

.layout-content {
  flex: 1;
  min-width: 0;
}

.layout-side {
  width: var(--sidebar-w);
  flex-shrink: 0;
  position: sticky;
  top: calc(var(--header-h) + 16px);
  align-self: flex-start;
  max-height: calc(100vh - var(--header-h) - 32px);
  overflow: auto;
}

@media (max-width: 1023px) {
  .layout-side { display: none; }
}

/* ---------- 网格 ---------- */
.grid {
  display: grid;
  gap: 12px;
  grid-template-columns: 1fr;          /* 360px 断点：单列 */
}

@media (min-width: 768px) {
  .grid { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 1024px) {
  .grid { grid-template-columns: repeat(3, 1fr); }
}

@media (min-width: 1440px) {
  .grid { grid-template-columns: repeat(4, 1fr); }
}

.grid-cards {
  display: grid;
  gap: 12px;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
}

/* ---------- 页脚 ---------- */
.site-footer {
  border-top: 1px solid var(--line);
  background: var(--bg-card);
  padding: 28px 0 92px; /* 底部预留移动端导航高度 */
  font-size: .9rem;
  color: var(--text-2);
}

.site-footer .footer-cols {
  display: grid;
  gap: 20px;
  grid-template-columns: 1fr;
}

@media (min-width: 768px) {
  .site-footer .footer-cols { grid-template-columns: 2fr 1fr 1fr; }
}

.site-footer h4 { color: var(--text); margin-bottom: 8px; font-size: .95rem; }
.site-footer a { display: block; padding: 3px 0; }
.site-footer a:hover { color: var(--brand); }

.footer-bottom {
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  font-size: .82rem;
  color: var(--text-3);
}

/* ---------- 移动端底部快捷导航 ---------- */
.bottom-nav {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 90;
  height: var(--nav-h);
  display: flex;
  background: color-mix(in srgb, var(--bg-card) 94%, transparent);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  backdrop-filter: saturate(180%) blur(12px);
  border-top: 1px solid var(--line);
}

.bottom-nav a {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  font-size: .72rem;
  color: var(--text-2);
  min-height: var(--nav-h);
}

.bottom-nav a svg { width: 22px; height: 22px; }
.bottom-nav a.active { color: var(--brand); font-weight: 600; }

@media (min-width: 768px) {
  .bottom-nav { display: none; }
  .site-footer { padding-bottom: 28px; }
}

/* ---------- 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  font-size: .85rem;
  color: var(--text-3);
  padding: 14px 0 0;
}

.breadcrumb a:hover { color: var(--brand); }
.breadcrumb .sep { opacity: .5; }
.breadcrumb [aria-current="page"] { color: var(--text-2); }