Examples updates (#24898)

* fix cover nav

* Improve signin visuals and alignment with that flexbox love

* rewrite cover example in flexbox

* lighten signin bg

* first pass at pricing example

* redo examples index with data file

* tighten up spacing a bit

* update navbar descriptions

* link pricing

* move that back

* property order

* Fix test errors.

* Compress pricing.png.

* add form validation example

* remove that

* rename that

* restyle and space out

* fix errors

* change order

* cleanup album css and styles

* tweak examples index

* make it a badge

* options

* improve sticky footer alignment

* redesign example index

* brand new blog layout

* start new screenshots

* new product example page a la apple

* add email field

* fix linter, remove unused blog css

* hook up feather icons to start

* redo dashboard

* fix linting

* add floating labels example

* formatting

* formatting

* lint

* fix values on select

* optional input, plus input group

* new dashboard image

* start to reboot the offcanvas example

* updated images

* new offcanvas mostly implemented

* linting

* edit description

* more description changes

* - Add vertical margin to album hero buttons for when they're stacked
- Adjust font-size and padding for pricing header and hero
- Fix checkout's stacked column margins, plus update their check/radio
markup
- Update product's utilities to be responsive
- Made blog cards somewhat responsive (needs a bit more work tbh)

* drop leading zero

* more linting

* swap empty images for holder, fix border

* dist the docs

* navbars have no margin-bottom to begin

* add css var, tweak padding for mobile

* comment headers

* nix commented out code

* nix the navbar structure for a custom one, stack it on mobile

* tweak heading button group for mobile

* Removed narrow jumbotron and justified nav examples as these are easily accomplished with new components in v4

* improve card sizing on pricing

* update and compress

2 files changed, 133 insertions, 0 deletions

diff --git a/docs/4.0/examples/floating-labels/floating-labels.css b/docs/4.0/examples/floating-labels/floating-labels.css
new file mode 100644
index 000000000..1eb04973a
--- /dev/null
+++ b/docs/4.0/examples/floating-labels/floating-labels.css
@@ -0,0 +1,87 @@
+:root {
+  --input-padding-x: .75rem;
+  --input-padding-y: .75rem;
+}
+
+html,
+body {
+  height: 100%;
+}
+
+body {
+  display: -ms-flexbox;
+  display: -webkit-box;
+  display: flex;
+  -ms-flex-align: center;
+  -ms-flex-pack: center;
+  -webkit-box-align: center;
+  align-items: center;
+  -webkit-box-pack: center;
+  justify-content: center;
+  padding-top: 40px;
+  padding-bottom: 40px;
+  background-color: #f5f5f5;
+}
+
+.form-signin {
+  width: 100%;
+  max-width: 420px;
+  padding: 15px;
+  margin: 0 auto;
+}
+
+.form-label-group {
+  position: relative;
+  margin-bottom: 1rem;
+}
+
+.form-label-group > input,
+.form-label-group > label {
+  padding: var(--input-padding-y) var(--input-padding-x);
+}
+
+.form-label-group > label {
+  position: absolute;
+  top: 0;
+  left: 0;
+  display: block;
+  width: 100%;
+  margin-bottom: 0; /* Override default `<label>` margin */
+  line-height: 1.5;
+  color: #495057;
+  border: 1px solid transparent;
+  border-radius: .25rem;
+  transition: all .1s ease-in-out;
+}
+
+.form-label-group input::-webkit-input-placeholder {
+  color: transparent;
+}
+
+.form-label-group input:-ms-input-placeholder {
+  color: transparent;
+}
+
+.form-label-group input::-ms-input-placeholder {
+  color: transparent;
+}
+
+.form-label-group input::-moz-placeholder {
+  color: transparent;
+}
+
+.form-label-group input::placeholder {
+  color: transparent;
+}
+
+.form-label-group input:not(:placeholder-shown) {
+  padding-top: calc(var(--input-padding-y) + var(--input-padding-y) * (2 / 3));
+  padding-bottom: calc(var(--input-padding-y) / 3);
+}
+
+.form-label-group input:not(:placeholder-shown) ~ label {
+  padding-top: calc(var(--input-padding-y) / 3);
+  padding-bottom: calc(var(--input-padding-y) / 3);
+  font-size: 12px;
+  color: #777;
+}
diff --git a/docs/4.0/examples/floating-labels/index.html b/docs/4.0/examples/floating-labels/index.html
new file mode 100644
index 000000000..b8a59bbdb
--- /dev/null
+++ b/docs/4.0/examples/floating-labels/index.html
@@ -0,0 +1,46 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
+    <meta name="description" content="">
+    <meta name="author" content="">
+    <link rel="icon" href="../../../../favicon.ico">
+
+    <title>Floating labels example for Bootstrap</title>
+
+    <!-- Bootstrap core CSS -->
+    <link href="../../../../dist/css/bootstrap.min.css" rel="stylesheet">
+
+    <!-- Custom styles for this template -->
+    <link href="floating-labels.css" rel="stylesheet">
+  </head>
+
+  <body>
+    <form class="form-signin">
+      <div class="text-center mb-4">
+        <img class="mb-4" src="https://getbootstrap.com/assets/brand/bootstrap-solid.svg" alt="" width="72" height="72">
+        <h1 class="h3 mb-3 font-weight-normal">Floating labels</h1>
+        <p>Build form controls with floating labels via the <code>:placeholder-shown</code> pseudo-element. <a href="https://caniuse.com/#feat=css-placeholder-shown">Works in latest Chrome, Safari, and Firefox.</a></p>
+      </div>
+
+      <div class="form-label-group">
+        <input type="email" id="inputEmail" class="form-control" placeholder="Email address" required autofocus>
+        <label for="inputEmail">Email address</label>
+      </div>
+
+      <div class="form-label-group">
+        <input type="password" id="inputPassword" class="form-control" placeholder="Password" required>
+        <label for="inputPassword">Password</label>
+      </div>
+
+      <div class="checkbox mb-3">
+        <label>
+          <input type="checkbox" value="remember-me"> Remember me
+        </label>
+      </div>
+      <button class="btn btn-lg btn-primary btn-block" type="submit">Sign in</button>
+      <p class="mt-5 mb-3 text-muted text-center">&copy; 2017</p>
+    </form>
+  </body>
+</html>