/* ====== 真题频道侧栏导航共享样式（index.html + exam-set.html 共用） ====== */

/* 学段TAB——灯笼样式 */
.tgb-nav {
  display: flex;
  border-bottom: 1px solid #2a2a4a;
  padding: 5px 8px;
}
.tgb-nav a {
  flex: 1;
  text-align: center;
  padding: 3px 0;
  font-size: 10px;
  font-weight: 400;
  color: #666688;
  letter-spacing: 1px;
  border-radius: 12px;
  margin: 0 4px;
  transition: all 0.15s;
  text-decoration: none;
  cursor: pointer;
}
.tgb-nav a:hover { background: rgba(255,255,255,0.03); color: #9999bb; }
.tgb-nav a.active {
  background: rgba(212, 175, 55, 0.12);
  color: #c9a84c;
  font-weight: 600;
  box-shadow: 0 0 6px rgba(212, 175, 55, 0.08);
}

/* 搜索框 */
.search-box { padding: 8px; }
.search-box input {
  width: 100%; padding: 6px 10px;
  border: 1px solid #2a2a4a; border-radius: 6px;
  background: #141428; color: #b0b0c8;
  font-size: 12px; outline: none;
}
.search-box input::placeholder { color: #555577; }
.search-box input:focus { border-color: #c9a84c; }

/* 模式TAB（套题/专题/刷题） */
.mode-nav {
  display: flex;
  border-bottom: 1px solid #2a2a4a;
}
.mode-nav a {
  flex: 1;
  text-align: center;
  padding: 6px 0;
  font-size: 11px;
  font-weight: 500;
  color: #666688;
  letter-spacing: 1px;
  transition: all 0.15s;
  text-decoration: none;
  cursor: pointer;
}
.mode-nav a:hover { background: rgba(255,255,255,0.03); color: #8888aa; }
.mode-nav a.active {
  color: #d4a847;
  font-weight: 600;
  background: rgba(212,168,71,0.08);
}

/* 树容器 */
.sidebar-nav .tree-container { display: none; }
.sidebar-nav .tree-container.active { display: block; }
.sidebar-nav { flex:1; padding:4px 0 20px; }
.tree-group { margin:2px 0; }
.tree-header {
  padding:7px 18px; font-size:12px; color:#d4a847;
  cursor:pointer; user-select:none; letter-spacing:1px; font-weight:600;
  display:flex; align-items:center; gap:6px;
}
.tree-header .arrow { font-size:8px; transition:transform .2s; color:#606078; }
.tree-header .arrow.open { transform:rotate(90deg); }
.tree-item {
  display:block; padding:5px 18px 5px 40px;
  font-size:12px; color:#606078;
  border-left:2px solid transparent; transition:all .12s; cursor:pointer;
}
.tree-item:hover { color:#e0e0f0; background: #252545; }
.tree-item.active {
  color: #e8c56a; border-left-color: #e8c56a;
  background: rgba(232,197,106,0.08);
}
.tree-item.sub-item { padding:3px 18px 3px 40px; font-size:11px; color:#606078; }
.tree-item.sub-item:hover { color:#d0d0e0; }

/* 底部页脚 */
.sidebar-footer {
  padding: 12px 18px; border-top: 1px solid #2a2a4a;
  font-size: 11px; text-align: center; flex-shrink: 0;
}
.sidebar-footer a { color: #555577; text-decoration: none; }