composant SelectFieldLineComponent : noir -> bleu, alignement du label à gauche et sur 3 colonnes.

src/app/components/select-field-line/select-field-line.component.html

 <div class="row">
     <!-- titre -->
-    <div class="col-sm-4 text-xs-left text-sm-right">
+    <div class="col-12 col-sm-3">
         {{_select.label}}
     </div>
 
     <!-- liste déroulante -->
-    <div class="col-sm-8">
-        <div class="btn-group" dropdown (click)="onSelect($event)">
-            <button dropdownToggle class="btn grey darken-3 dropdown-toggle waves-light" type="button" mdbRippleRadius>
-                {{currentLabel}}
-            </button>
-            <div class="dropdown-menu">
-                <a class="dropdown-item" *ngFor="let e of entries" [value]=e.value>{{e.label}}</a>
-            </div>
+    <div class="btn-group col-12 col-sm-9" dropdown (click)="onSelect($event)">
+        <button dropdownToggle class="btn btn-primary dropdown-toggle waves-light my-1" type="button" mdbRippleRadius>
+            {{currentLabel}}
+        </button>
+        <div class="dropdown-menu">
+            <a class="dropdown-item" *ngFor="let e of entries" [value]=e.value>{{e.label}}</a>
         </div>
     </div>
 </div>
\ No newline at end of file