Add border classes and slider arrow

less/slider.less

@@ -1,4 +1,25 @@
+@slider-arrow-background: @global-background;
+@slider-arrow-width: 50px;
+@slider-arrow-margin: 5px;
+
 .hook-slider-misc() {
+  .uk-slider-arrow {
+    height: 100%;
+    width: @slider-arrow-width;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    background: @slider-arrow-background;
+
+    &.uk-slider-left {
+      padding-right: @slider-arrow-margin;
+    }
+
+    &.uk-slider-right {
+      padding-left: @slider-arrow-margin;
+    }
+  }
+
   .uk-slider-container-tabs:extend(.uk-slider-container) {
     position: relative;
 
@@ -9,14 +30,5 @@
     & .uk-subnav {
       margin-left: -@subnav-margin-horizontal;
     }
-
-    &:has(.uk-tab)::before {
-      content: "";
-      position: absolute;
-      bottom: 0;
-      left: 0;
-      right: 0;
-      border-bottom: @tab-border-width solid @tab-border;
-    }
   }
 }

less/utility.less

@@ -1,7 +1,32 @@
 @dropcap-font-size: @global-line-height * 3;
 @border-rounded-border-radius: @global-border-radius;
 
+@border-width: @global-border-width;
+@border-color: @global-border;
+
+
 .hook-utility-misc() {
+  /* Border */
+  .uk-border {
+    border: @border-width solid @border-color;
+  }
+
+  .uk-border-bottom {
+    border-bottom: @border-width solid @border-color;
+  }
+
+  .uk-border-top {
+    border-top: @border-width solid @border-color;
+  }
+
+  .uk-border-left {
+    border-left: @border-width solid @border-color;
+  }
+
+  .uk-border-right {
+    border-right: @border-width solid @border-color;
+  }
+
   /* Box-shadow */
   .uk-box-shadow-default, .uk-box-shadow-default-hover:hover {
     box-shadow: @global-default-shadow;