introduce "view navigation panel" and "atlas selection panel"

docs/basics/exploring_3d_parcellation_maps.md

 # Exploring 3D Parcellation Maps
 
-On the bottom left of the viewer, you find selectors for choosing the species, reference space, and parcellation map. The latter two are shown only if more than one option is available.
+On the bottom left of the viewer, you find the atlas selection panel which provides buttons choosing the species, reference space, and parcellation map. The latter two are shown only if more than one option is available.
 
 ![](https://data-proxy.ebrains.eu/api/v1/buckets/reference-atlas-data/static/siibra-explorer-chips.png){ style="width:700px"}
 

docs/basics/storing_and_sharing_3d_views.md

@@ -11,7 +11,7 @@ Any views in `siibra-explorer` can be shared via their URLs. You can use any nat
 
 Whilst `siibra-explorer` encodes the current view directly in the URL, such full URLs are quite long and not easily recitable or memorable. You can create short URLs for the current view directly in `siibra-explorer`. To do so,
 
-1. expand the *navigation panel*, 
+1. click the *view navigation panel* on the top left (see [main UI elements](../ui/main_elements.md#-and-plugins), 
 2. click the "share icon", then 
 3. select `Create custom URL`.
 
@@ -24,7 +24,7 @@ Whilst `siibra-explorer` encodes the current view directly in the URL, such full
 
 While you can use any screenshot tool provided by your browser or operating system, `siibra-explorer` offers a dedicated screenshot function which generates a clean image of the current 3D view which hides other user interface elements. To access the screenshot tool, 
 
-1. choose the tool menu (`᎒᎒᎒`) from the top right (see [main UI elements](../ui/main_elements.md#tools-and-plugins)), then 
+1. open the tool menu (`᎒᎒᎒`) from the top right (see [main UI elements](../ui/main_elements.md#tools-and-plugins)), then 
 2. select `Screenshot`.
 
 ![Creating a screenshot in siibra-explorer](https://data-proxy.ebrains.eu/api/v1/buckets/reference-atlas-data/static/siibra-explorer-screenshots.png){ style="width:700px"}

docs/getstarted/ui.md

@@ -12,16 +12,18 @@ The precise layout of the 3D view depends on the select reference space.
 - (Middle) The volumetric views support ultrahigh-resolution data, and can be zoomed in if the underlying image data allows. Each of the 3 planar views can be maximized using the "[ ]" icon in each view.
 - (Right) For pure surface spaces, such as the fsaverage space, the viewer shows only a 3D view.
 
+For more information, read about [Exploring 3D parcellation maps](../basics/exploring_3d_parcellation_maps.md).
 
 
-## Navigation panel
-At the top left of the user interface, `siibra-explorer` displays the 3D coordinate of the currently selected center of view together with the navigation icon 🧭. When you click it with the mouse pointer, a navigation panel opens, which allows to enter a different coordinates, and create a shareable link to the current view (see ["Storing and sharing 3D views"](../basics/storing_and_sharing_3d_views.md)).
+## View navigation panel
+At the top left of the user interface, `siibra-explorer` displays the 3D coordinate of the currently selected center of view together with the navigation icon 🧭. When you click it with the mouse pointer, a navigation panel for the 3D view opens, which allows to enter different coordinates, copy the current coordinates, and create a shareable link to the current view (see ["Storing and sharing 3D views"](../basics/storing_and_sharing_3d_views.md)).
 
 ![](https://data-proxy.ebrains.eu/api/v1/buckets/reference-atlas-data/static/siibra-explorer-navigation.png){ style="width:500px"}
 
-## Parcellation map selectors 
-At the bottom of the window, you find buttons to switch between different species, different reference templates, and different parcellation maps.
-Working with different maps is described in ["Exploring parcellation maps"](../basics/exploring_3d_parcellation_maps.md)). 
+## Atlas selection panel
+
+At the bottom of the window, you find buttons to switch between different species, reference templates and parcellation maps.
+Working with parcellation maps is described in ["Exploring parcellation maps"](../basics/exploring_3d_parcellation_maps.md)). 
 Note that some of the buttons may be hidden in case that only one option is available.
 
 ![](https://data-proxy.ebrains.eu/api/v1/buckets/reference-atlas-data/static/siibra-explorer-chips.png){ style="width:500px"}
@@ -32,8 +34,8 @@ At the top right of the viewer, there are several icons guiding you to additiona
 
 ![](https://data-proxy.ebrains.eu/api/v1/buckets/reference-atlas-data/static/siibra-explorer-tools.png){ style="width:500px"}
 
-#### ⓘ Help panel
-The help button (ⓘ ) opens information about keyboard shortcuts and terms of use. Here you can also launch the interactive quick tour, which is started automatically when you use `siibra-explorer` for the first time.
+#### (?) Help panel
+The help button (?) opens information about keyboard shortcuts and terms of use. Here you can also launch the interactive quick tour, which is started automatically when you use `siibra-explorer` for the first time.
 
 #### <u>↓</u> Download current view 
 The download button (<u>↓</u>) will retrieve the reference template and parcellation map currently displayed in a zip file package