/* layout.css — 应用骨架 + 三档响应式 */

.app {
  display: grid;
  min-height: 100vh;
  grid-template-columns: var(--sidebar-w) 1fr;
  grid-template-rows: var(--topbar-h) 1fr var(--tabbar-h);
  grid-template-areas:
    "side top"
    "side main"
    "side tab";
}

.topbar { grid-area: top; }
.sidebar { grid-area: side; }
.main {
  grid-area: main;
  padding: var(--gutter);
  overflow: auto;
  min-height: 0; /* grid 子项可收缩，保证内部滚动 */
  min-width: 0;
  scrollbar-width: none !important;
  -ms-overflow-style: none !important;
}
.main::-webkit-scrollbar {
  display: none !important;
  width: 0 !important;
  height: 0 !important;
}
.tabbar { grid-area: tab; display: none; }

/* ====== 内置管理员模式：无侧栏，移动端保留底栏 Tab ====== */
.app.admin-mode {
  grid-template-columns: 1fr;
  grid-template-rows: var(--topbar-h) 1fr;
  grid-template-areas:
    "top"
    "main";
}
.app.admin-mode .sidebar { display: none !important; }

/* 顶部条 */
.topbar {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 0 var(--gutter);
  background: var(--topbar-bg);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  border-bottom: 1px solid var(--panel-border);
  position: sticky; top: 0; z-index: 20;
}
.topbar .brand {
  display: flex; align-items: center; gap: 10px; font-weight: 700;
}
/* 品牌字：固定多色渐变（与主题解耦，所有主题下都可见且不喧宾夺主） */
.topbar .brand .brand-text {
  font-size: 18px;
  font-weight: 800;
  letter-spacing: 4px;
  padding-left: 2px;
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-2) 50%, color-mix(in srgb, var(--primary-2) 60%, var(--accent)) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  position: relative;
}
.topbar .brand .brand-text::after {
  content: '';
  position: absolute; left: 2px; right: 0; bottom: -4px; height: 2px;
  background: linear-gradient(90deg, color-mix(in srgb, var(--primary) 70%, transparent), color-mix(in srgb, var(--primary-2) 50%, transparent), transparent);
  border-radius: 2px;
}
.topbar .spacer { flex: 1; }
.topbar-action {
  display: none;
  flex-shrink: 0;
  align-items: center;
  margin-right: 4px;
}
.topbar-action:not(:empty) {
  display: flex;
}
.topbar .pill {
  font-size: 12px; color: var(--muted); padding: 4px 10px;
  border: 1px solid var(--panel-border); border-radius: 999px;
}
.topbar .pill b { color: var(--text); margin-left: 6px; font-weight: 600; }
/* 顶栏左侧返回按钮（由 setTopBack() 控制显隐） */
.topbar .topbar-back {
  width: 36px; height: 36px; flex-shrink: 0;
  border-radius: 10px;
  border: none; background: transparent;
  color: var(--text);
  display: inline-flex; align-items: center; justify-content: center;
  cursor: pointer; padding: 0;
  transition: background .15s, color .15s, transform .12s;
}
.topbar .topbar-back:hover { background: var(--hover-bg); color: var(--primary); }
.topbar .topbar-back:active { transform: translateX(-2px); }
.topbar .topbar-back svg { display: block; }
.topbar .hamburger {
  display: none; width: 36px; height: 36px; border-radius: 10px;
  border: 1px solid var(--panel-border); background: transparent;
  align-items: center; justify-content: center;
}

/* 侧栏 */
.sidebar {
  background: linear-gradient(180deg, var(--topbar-bg), var(--bg-elev));
  border-right: 1px solid var(--panel-border);
  padding: 14px 10px;
  display: flex; flex-direction: column; gap: 6px;
  position: sticky; top: 0; height: 100vh;
  overflow: auto;
}
.sidebar .nav-item {
  display: flex; align-items: center; gap: 10px;
  padding: 10px 12px; border-radius: 10px;
  color: var(--muted); cursor: pointer;
  transition: background .15s, color .15s;
  min-height: 44px;
}
.sidebar .nav-item:hover { background: var(--hover-bg); color: var(--text); }
.sidebar .nav-item.active {
  color: var(--text);
  background: var(--track-bg);
  box-shadow: inset 0 0 0 1px var(--primary);
}
.sidebar .nav-item svg { width: 18px; height: 18px; flex-shrink: 0; }
.sidebar .nav-section {
  margin-top: 14px; padding: 0 12px;
  font-size: 11px; color: var(--muted); text-transform: uppercase; letter-spacing: 1px;
}
.sidebar .account-list {
  margin-top: 6px; display: flex; flex-direction: column; gap: 4px;
}
.sidebar .account-list .account-row {
  display: flex; align-items: center; gap: 8px;
  padding: 8px 12px; border-radius: 8px; cursor: pointer;
  font-size: 13px;
}
.sidebar .account-list .account-row:hover { background: var(--hover-bg); }
.sidebar .account-list .account-row.active { background: var(--track-bg); color: var(--text); }
.sidebar .account-list .dot {
  width: 8px; height: 8px; border-radius: 50%; background: var(--muted); flex-shrink: 0;
}
.sidebar .account-list .dot.online { background: var(--accent); box-shadow: 0 0 8px var(--accent); }
.sidebar .account-list .name { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* 底部 Tab（仅手机） */
.tabbar {
  background: var(--tabbar-bg);
  backdrop-filter: blur(16px);
  border-top: 1px solid var(--panel-border);
  padding-bottom: env(safe-area-inset-bottom);
}
.tabbar .tab {
  flex: 1; display: flex; flex-direction: column; align-items: center; gap: 2px;
  padding: 8px 4px; font-size: 11px; color: var(--muted);
  background: transparent; border: none; cursor: pointer;
  transition: color .15s, background .15s;
}
.tabbar .tab:hover { color: var(--text); }
.tabbar .tab.active {
  color: var(--primary);
  background: var(--hover-bg);
  font-weight: 600;
}
.tabbar .tab svg { width: 22px; height: 22px; }

/* 抽屉遮罩 */
.drawer-mask {
  position: fixed; inset: 0; background: rgba(0, 0, 0, .55);
  z-index: 30; backdrop-filter: blur(4px);
}

/* ====== 平板：侧栏收为图标 ====== */
@media (max-width: 1199px) {
  :root { --sidebar-w: 72px; }
  .sidebar .nav-item .label,
  .sidebar .nav-section,
  .sidebar .account-list .name { display: none; }
  .sidebar .nav-item { justify-content: center; padding: 10px 8px; }
}

/* ====== 手机：纯移动端应用结构（保留全局顶栏） ====== */
@media (max-width: 767px) {
  :root { --sidebar-w: 0px; --topbar-h: 52px; --tabbar-h: 60px; }
  /* 锁死整体视口高度，让 .main 内部滚动；底部 tabbar 不会随页面滚动 */
  html, body { height: 100%; overflow: hidden; }
  .app {
    height: 100vh;
    height: 100dvh;
    min-height: 0;
    overflow: hidden;
    grid-template-columns: 1fr;
    grid-template-rows: var(--topbar-h) 1fr var(--tabbar-h);
    grid-template-areas:
      "top"
      "main"
      "tab";
  }
  .topbar { 
    display: flex; position: sticky; top: 0; z-index: 40; 
    background: rgba(255, 255, 255, 0.85); /* 默认亮色 fallback */
    background: var(--panel);
    backdrop-filter: blur(12px) saturate(120%); -webkit-backdrop-filter: blur(12px) saturate(120%);
    border-bottom: 1px solid var(--panel-border);
    padding: 0 16px;
    align-items: center;
  }
  .topbar .hamburger { display: none; }
  .topbar .brand-text {
    /* 在移动端将顶栏的品牌名替换为当前页面标题样式 */
    font-size: 20px;
    font-weight: 700;
    color: var(--text);
    background: none;
    -webkit-text-fill-color: initial;
    letter-spacing: 0.5px;
  }
  .sidebar { display: none; }
  .main { padding-bottom: calc(var(--gutter) + env(safe-area-inset-bottom)); }
  .tabbar {
    display: flex;
    position: sticky; bottom: 0; z-index: 25;
  }
  /* 子页（带返回按钮的页面）隐藏底部 tabbar */
  body.subpage .tabbar { display: none !important; }
  body.subpage .app {
    grid-template-rows: var(--topbar-h) 1fr;
    grid-template-areas: "top" "main";
  }
  body.subpage .topbar {
    gap: 4px;
    padding: 0 8px 0 2px;
    flex-wrap: nowrap;
  }
  body.subpage .topbar .topbar-back {
    width: 28px;
    height: 28px;
    margin-left: 0;
    margin-right: -2px;
  }
  body.subpage .topbar .topbar-back svg {
    width: 20px;
    height: 20px;
  }
  body.subpage .topbar .brand {
    gap: 0;
    min-width: auto;
    flex-shrink: 0;
  }
  body.subpage .topbar .brand-text {
    font-size: 16px;
    letter-spacing: 0 !important;
    white-space: nowrap;
    overflow: visible;
    text-overflow: clip;
    max-width: none;
    line-height: 1.2;
    flex-shrink: 0;
  }
  body.subpage .topbar .brand-text::after {
    display: none;
  }
  body.subpage .topbar .spacer {
    flex: 1 1 0;
    min-width: 0;
  }
  body.subpage .topbar-action {
    margin-right: 0;
    min-width: 0;
    flex-shrink: 1;
  }
  body.subpage .topbar .avatar-placeholder {
    width: 28px;
    height: 28px;
    flex-shrink: 0;
    margin-left: 2px;
  }
  body.subpage .topbar:has(.topbar-action:not(:empty)) {
    padding-left: 0;
    gap: 2px;
  }
  body.subpage .topbar:has(.topbar-action:not(:empty)) .topbar-back {
    width: 26px;
    margin-right: -4px;
  }
  body.subpage .topbar:has(.topbar-action:not(:empty)) .brand-text {
    font-size: 15px;
  }
  /* 内置管理员：移动端显示「后台 / 我的」底栏 */
  .app.admin-mode {
    grid-template-rows: var(--topbar-h) 1fr var(--tabbar-h);
    grid-template-areas: "top" "main" "tab";
  }
  .app.admin-mode .tabbar { display: flex; }
  body.subpage .app.admin-mode {
    grid-template-rows: var(--topbar-h) 1fr;
    grid-template-areas: "top" "main";
  }
  body.subpage .app.admin-mode .tabbar { display: none !important; }
}