[tree] styling fixes

dist/styles/Tree.css

@@ -54,15 +54,15 @@ li .leaf:hover a.settings {
   margin-right: 19px;
 }
 .tree .lefthanded ul li {
-  margin-right: 15px;
+  margin-right: 10px;
   padding-right: 5px;
 }
-.tree .lefthanded ul li::after {
+.tree .lefthanded ul li.with-children::after {
   background-color: #000;
   right: -10px;
-  width: 10px;
+  width: 5px;
 }
-.tree .lefthanded ul li::before {
+.tree .lefthanded ul li.with-children::before {
   background-color: #000;
   right: -10px;
   width: 1px;
@@ -74,20 +74,20 @@ li .leaf:hover a.settings {
   margin-left: 19px;
 }
 .tree .righthanded ul li {
-  margin-left: 15px;
+  margin-left: 10px;
   padding-left: 5px;
 }
-.tree .righthanded ul li::after {
+.tree .righthanded ul li.with-children::after {
   background-color: #000;
   left: -10px;
-  width: 10px;
+  width: 5px;
 }
-.tree .righthanded ul li::before {
+.tree .righthanded ul li.with-children::before {
   background-color: #000;
   left: -10px;
   width: 1px;
 }
-.tree .righthanded ul li:only::before {
+.tree .righthanded ul li.with-children:only::before {
   background-color: #000;
   right: 10px;
 }

dist/styles/Tree.sass

@@ -48,12 +48,13 @@ li
     ul
       margin-right : 19px
       li
-        margin-right: 15px
+        margin-right: 10px
         padding-right: 5px
+        &.with-children
           &::after
             background-color: #000
             right: -10px
-          width: 10px
+            width: 5px
           &::before
             background-color: #000
             right: -10px
@@ -66,12 +67,13 @@ li
     ul
       margin-left : 19px
       li
-        margin-left: 15px
+        margin-left: 10px
         padding-left: 5px
+        &.with-children
           &::after
             background-color: #000
             left: -10px
-          width: 10px
+            width: 5px
           &::before
             background-color: #000
             left: -10px

src/Gargantext/Components/Forest/Tree.purs

@@ -199,7 +199,7 @@ toHtml p@{ asyncTasks
 
         let withId (NTree (LNode {id: id'}) _) = id'
 
-        pure $ H.li {} $
+        pure $ H.li { className: if A.null ary then "no-children" else "with-children" } $
           [ nodeMainSpan (A.null ary) 
                          { id
                          , dispatch: pAction