[simple theme] minor css fixes

* remove hover effect from vim help modal
* remove bold font weight from active item in prefenreces tab bar
* remove margin from answer box to unify with rest of result page

searx/static/themes/simple/src/less/style.less

@@ -445,7 +445,7 @@ article[data-vim-selected].category-social {
   border: 1px solid var(--color-answer-border);
   background: var(--color-answer-background);
   padding: @result-padding;
-  margin: 1rem @results-tablet-offset;
+  margin: 1rem 0;
   margin-top: 0;
   color: var(--color-answer-font);
   .rounded-corners;

searx/static/themes/simple/src/less/toolkit.less

@@ -157,7 +157,7 @@ div.selectable_url {
     vertical-align: text-top;
 
     &:hover {
-      background: transparent;
+      background: transparent !important;
     }
   }
 
@@ -267,7 +267,6 @@ div.selectable_url {
     border-bottom: 2px solid var(--color-categories-item-border-selected);
     background: var(--color-categories-item-selected);
     color: var(--color-categories-item-selected-font);
-    font-weight: bold;
     letter-spacing: -0.1px;
   }