Add Bootstrap and Bootstrap Icons files

assets/paige/bootstrap/css/_close.scss

@@ -0,0 +1,61 @@
+// Transparent background and border properties included for button version.
+// iOS requires the button element instead of an anchor tag.
+// If you want the anchor version, it requires `href="#"`.
+// See https://developer.mozilla.org/en-US/docs/Web/Events/click#Safari_Mobile
+
+.btn-close {
+  --#{$prefix}btn-close-color: #{$btn-close-color};
+  --#{$prefix}btn-close-bg: #{ escape-svg($btn-close-bg) };
+  --#{$prefix}btn-close-opacity: #{$btn-close-opacity};
+  --#{$prefix}btn-close-hover-opacity: #{$btn-close-hover-opacity};
+  --#{$prefix}btn-close-focus-shadow: #{$btn-close-focus-shadow};
+  --#{$prefix}btn-close-focus-opacity: #{$btn-close-focus-opacity};
+  --#{$prefix}btn-close-disabled-opacity: #{$btn-close-disabled-opacity};
+  --#{$prefix}btn-close-white-filter: #{$btn-close-white-filter};
+
+  box-sizing: content-box;
+  width: $btn-close-width;
+  height: $btn-close-height;
+  padding: $btn-close-padding-y $btn-close-padding-x;
+  color: var(--#{$prefix}btn-close-color);
+  background: transparent var(--#{$prefix}btn-close-bg) center / $btn-close-width auto no-repeat; // include transparent for button elements
+  border: 0; // for button elements
+  @include border-radius();
+  opacity: var(--#{$prefix}btn-close-opacity);
+
+  // Override <a>'s hover style
+  &:hover {
+    color: var(--#{$prefix}btn-close-color);
+    text-decoration: none;
+    opacity: var(--#{$prefix}btn-close-hover-opacity);
+  }
+
+  &:focus {
+    outline: 0;
+    box-shadow: var(--#{$prefix}btn-close-focus-shadow);
+    opacity: var(--#{$prefix}btn-close-focus-opacity);
+  }
+
+  &:disabled,
+  &.disabled {
+    pointer-events: none;
+    user-select: none;
+    opacity: var(--#{$prefix}btn-close-disabled-opacity);
+  }
+}
+
+@mixin btn-close-white() {
+  filter: var(--#{$prefix}btn-close-white-filter);
+}
+
+.btn-close-white {
+  @include btn-close-white();
+}
+
+@if $enable-dark-mode {
+  @include color-mode(dark) {
+    .btn-close {
+      @include btn-close-white();
+    }
+  }
+}