1 files changed, 85 insertions, 0 deletions
diff --git a/scss/forms/_floating-labels.scss b/scss/forms/_floating-labels.scss
new file mode 100644
index 0000000000..b35f1c3bdc
--- /dev/null
+++ b/scss/forms/_floating-labels.scss
@@ -0,0 +1,85 @@
+// stylelint-disable selector-no-vendor-prefix
+
+.form-floating {
+  position: relative;
+
+  > .form-control,
+  > .form-select {
+    height: $form-floating-height;
+    padding: $form-floating-padding-y $form-floating-padding-x;
+  }
+
+  > label {
+    position: absolute;
+    top: 0;
+    left: 0;
+    height: 100%; // allow textareas
+    padding: $form-floating-padding-y $form-floating-padding-x;
+    pointer-events: none;
+    border: $input-border-width solid transparent; // Required for aligning label's text with the input as it affects inner box model
+    transform-origin: 0 0;
+    @include transition($form-floating-transition);
+  }
+
+  // stylelint-disable no-duplicate-selectors
+  > .form-control {
+    &::placeholder {
+      color: transparent;
+    }
+
+    &:focus,
+    &:not(:placeholder-shown) {
+      padding-top: $form-floating-input-padding-t;
+      padding-bottom: $form-floating-input-padding-b;
+    }
+    // Duplicated because `:-webkit-autofill` invalidates other selectors when grouped
+    &:-webkit-autofill {
+      padding-top: $form-floating-input-padding-t;
+      padding-bottom: $form-floating-input-padding-b;
+    }
+  }
+
+  > .form-select {
+    padding-top: $form-floating-input-padding-t;
+    padding-bottom: $form-floating-input-padding-b;
+  }
+
+  > .form-control:focus,
+  > .form-control:not(:placeholder-shown),
+  > .form-select {
+    ~ label {
+      opacity: $form-floating-label-opacity;
+      transform: $form-floating-label-transform;
+    }
+  }
+  // Duplicated because `:-webkit-autofill` invalidates other selectors when grouped
+  > .form-control:-webkit-autofill {
+    ~ label {
+      opacity: $form-floating-label-opacity;
+      transform: $form-floating-label-transform;
+    }
+  }
+  // stylelint-enable no-duplicate-selectors
+}
+
+
+//
+// Fallback for classic Edge
+//
+
+@supports (-ms-ime-align: auto) {
+  .form-floating {
+    display: flex;
+    flex-direction: column-reverse;
+  }
+  .form-floating > label {
+    position: static;
+    padding: 0;
+    margin-bottom: calc(#{$form-floating-padding-y} / 2); // stylelint-disable-line function-disallowed-list
+    border: 0;
+    @include transition(none);
+  }
+  .form-floating > .form-control::-ms-input-placeholder {
+    color: $input-placeholder-color;
+  }
+}