/* bubu12key.top 文档站 - 多页框架外壳(左侧导航 + 右侧 iframe)。白灰商务风格 */
:root {
  --bg-primary: #ffffff;
  --bg-secondary: #f8f9fa;
  --bg-tertiary: #f1f3f4;
  --text-primary: #202124;
  --text-secondary: #5f6368;
  --text-muted: #80868b;
  --border-color: #dadce0;
  --accent-color: #1a73e8;
  --accent-soft: rgba(26, 115, 232, 0.08);
  --sidebar-w: 268px;
  --topbar-h: 52px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body { height: 100%; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  font-size: 14px;
  color: var(--text-primary);
  background: var(--bg-primary);
  -webkit-font-smoothing: antialiased;
}

/* ===== 顶栏(移动端可见)===== */
.topbar {
  display: none;
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--topbar-h);
  align-items: center;
  gap: 12px;
  padding: 0 16px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  z-index: 40;
}
.topbar #menu-toggle {
  font-size: 20px;
  line-height: 1;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--text-primary);
  padding: 4px 8px;
}
.topbar-brand { font-weight: 600; font-size: 15px; }

/* ===== 侧边栏 ===== */
.sidebar {
  position: fixed;
  left: 0; top: 0;
  width: var(--sidebar-w);
  height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg-secondary);
  border-right: 1px solid var(--border-color);
  z-index: 30;
}

.sidebar-brand {
  padding: 18px 18px 12px;
  flex: 0 0 auto;
}
.sidebar-brand a {
  display: block;
  font-size: 18px;
  font-weight: 700;
  color: var(--text-primary);
  text-decoration: none;
  letter-spacing: 0.2px;
}
.sidebar-brand small {
  display: block;
  font-size: 12px;
  font-weight: 400;
  color: var(--text-muted);
  margin-top: 2px;
}

.sidebar-search {
  padding: 0 14px 10px;
  flex: 0 0 auto;
}
.sidebar-search input {
  width: 100%;
  padding: 8px 12px;
  font-size: 13px;
  color: var(--text-primary);
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  outline: none;
}
.sidebar-search input:focus { border-color: var(--accent-color); }

.sidebar nav {
  flex: 1 1 auto;
  overflow-y: auto;
  padding: 4px 0 28px;
}

.nav-group { margin-bottom: 6px; }
.nav-group-title {
  padding: 12px 18px 6px;
  font-size: 11.5px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.4px;
}
.nav-group ul { list-style: none; }
.nav-link {
  display: block;
  padding: 6px 18px 6px 22px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 13.5px;
  line-height: 1.5;
  border-left: 2px solid transparent;
}
.nav-link:hover { background: var(--bg-tertiary); color: var(--text-primary); }
.nav-link.active {
  background: var(--accent-soft);
  color: var(--accent-color);
  border-left-color: var(--accent-color);
  font-weight: 600;
}

/* ===== 内容区 ===== */
.content {
  margin-left: var(--sidebar-w);
  height: 100vh;
}
#viewer {
  width: 100%;
  height: 100%;
  border: 0;
  display: block;
  background: var(--bg-primary);
}

/* 移动端遮罩 */
.scrim {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.35);
  z-index: 20;
}

/* 侧栏滚动条 */
.sidebar nav::-webkit-scrollbar { width: 7px; }
.sidebar nav::-webkit-scrollbar-track { background: transparent; }
.sidebar nav::-webkit-scrollbar-thumb { background: var(--border-color); border-radius: 4px; }
.sidebar nav::-webkit-scrollbar-thumb:hover { background: var(--text-muted); }

/* ===== 响应式:移动端抽屉 ===== */
@media (max-width: 860px) {
  .topbar { display: flex; }
  .sidebar {
    top: 0;
    transform: translateX(-100%);
    transition: transform 0.22s ease;
    box-shadow: 2px 0 12px rgba(0, 0, 0, 0.12);
  }
  body.nav-open .sidebar { transform: translateX(0); }
  body.nav-open .scrim { display: block; }
  .content {
    margin-left: 0;
    height: 100vh;
    padding-top: var(--topbar-h);
  }
}