set svg fill color for spring theme

src/client/styles/scss/theme/_apply-colors-dark.scss

@@ -14,7 +14,6 @@ $bgcolor-table-hover: lighten($bgcolor-table, 7.5%) !default;
 $bgcolor-sidebar-list-group: $bgcolor-list !default;
 $color-tags: #949494 !default;
 $bgcolor-tags: $dark !default;
-$icon-color: $color-global !default;
 
 // override bootstrap variables
 $border-color: $gray-700;
@@ -365,14 +364,3 @@ body.on-edit {
     background-color: $bgcolor-tags;
   }
 }
-
-/*
- * GROWI user page
- */
-.grw-page-list-m {
-  .grw-page-list-title-m {
-    svg {
-      fill: $icon-color;
-    }
-  }
-}

src/client/styles/scss/theme/_apply-colors-light.scss

@@ -14,7 +14,6 @@ $bgcolor-table-hover: rgba(black, 0.075) !default;
 $bgcolor-sidebar-list-group: $bgcolor-list !default;
 $color-tags: $gray-500 !default;
 $bgcolor-tags: $gray-200 !default;
-$icon-color: $color-global !default;
 
 // override bootstrap variables
 $border-color: $gray-200;
@@ -295,14 +294,3 @@ $table-hover-bg: $bgcolor-table-hover;
     background-color: $bgcolor-tags;
   }
 }
-
-/*
- * GROWI user page
- */
-.grw-page-list-m {
-  .grw-page-list-title-m {
-    svg {
-      fill: $icon-color;
-    }
-  }
-}

src/client/styles/scss/theme/spring.scss

@@ -90,9 +90,6 @@ html[dark] {
   // admin theme box
   $color-theme-color-box: darken($primary, 20%);
 
-  // color of icons
-  $icon-color: $subthemecolor;
-
   @import 'apply-colors';
   @import 'apply-colors-light';
 
@@ -149,6 +146,10 @@ html[dark] {
   h1,
   h2 {
     color: $subthemecolor;
+
+    svg {
+      fill: $subthemecolor;
+    }
   }
 
   .nav.nav-tabs {