feat: 侧边栏菜单胶囊高亮效果

- 悬停: 半透明白色背景 rgba(255,255,255,0.06)
- 选中: 半透明蓝色背景 rgba(22,93,255,0.12) + 蓝色图标
- 去掉底部横线和颜色突变
- 平滑 0.2s 过渡动画
- 子菜单同样适用

clientarea/hgcloud/css/dark-override.css

@@ -35,6 +35,76 @@ html, body {
   filter: brightness(1.1);
 }
 
+/* ============ 侧边栏菜单 — 胶囊高亮 ============ */
+.menu-top .el-menu-item {
+  color: #8B949E !important;
+  border-radius: 8px !important;
+  margin: 2px 0 !important;
+  transition: all 0.2s !important;
+  border-bottom: none !important;
+}
+
+.menu-top .el-menu-item i {
+  color: #8B949E !important;
+  transition: color 0.2s !important;
+}
+
+.menu-top .el-menu-item:hover {
+  background-color: rgba(255, 255, 255, 0.06) !important;
+  color: #E6E8EB !important;
+  border-bottom: none !important;
+}
+
+.menu-top .el-menu-item:hover i {
+  color: #E6E8EB !important;
+}
+
+.menu-top .el-menu-item.is-active {
+  background-color: rgba(22, 93, 255, 0.12) !important;
+  color: #FFFFFF !important;
+  border-bottom: none !important;
+}
+
+.menu-top .el-menu-item.is-active i {
+  color: #165DFF !important;
+}
+
+/* 子菜单 */
+.menu-top .el-submenu__title {
+  color: #8B949E !important;
+  border-radius: 8px !important;
+  transition: all 0.2s !important;
+}
+
+.menu-top .el-submenu__title i {
+  color: #8B949E !important;
+}
+
+.menu-top .el-submenu__title:hover {
+  background-color: rgba(255, 255, 255, 0.06) !important;
+  color: #E6E8EB !important;
+}
+
+.menu-top .el-submenu__title:hover i {
+  color: #E6E8EB !important;
+}
+
+.menu-top .el-submenu .el-menu-item:hover {
+  background-color: rgba(255, 255, 255, 0.06) !important;
+  color: #E6E8EB !important;
+}
+
+.menu-top .el-submenu .el-menu-item.is-active {
+  background-color: rgba(22, 93, 255, 0.12) !important;
+  color: #FFFFFF !important;
+}
+
+/* Element UI 菜单整体背景 */
+.el-menu {
+  background-color: transparent !important;
+  border-right: none !important;
+}
+
 /* ============ 顶栏 ============ */
 .el-header {
   background: rgba(13, 17, 23, 0.85) !important;