remove scss

src/client/styles/scss/_override-bootstrap.scss

@@ -21,43 +21,3 @@
     }
   }
 }
-
-//** override bootstrap nav nav-tabs nav-item
-@mixin grw-nav-tab-set {
-  position: relative;
-  text-align: center;
-  $active-tab-border-width: 1px;
-  $active-tab-border-bg: white;
-  a {
-    display: block;
-    padding: 10px 15px;
-    font-size: $nav-main-tab-font-size;
-  }
-  &.active {
-    // TODO：Active class must be switching by user control.
-    border: $active-tab-border-width solid $grw-line-light-gray;
-    border-bottom: initial;
-  }
-  // border for tab is hidden as inner width white border, and then become unevenness.
-  &.active::before {
-    position: absolute;
-    bottom: 0;
-    left: 0;
-    display: block;
-    width: 100%;
-    content: '';
-    border-bottom: $active-tab-border-width solid $active-tab-border-bg;
-  }
-}
-
-.nav.nav-tabs > .nav-item {
-  @include grw-nav-tab-set;
-}
-
-.nav.nav-tabs.grw-nab-tabs-left-top > .nav-item {
-  @include grw-nav-tab-set;
-  a {
-    min-width: 95px;
-    padding: 10px 0;
-  }
-}