Add challenge solution

Added a solution. Please let me know if this is submitted incorrectly or in the wrong location.

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curriculum/challenges/english/01-responsive-web-design/basic-css/add-borders-around-your-elements.english.md

@@ -101,14 +101,69 @@ tests:
 
 </div>
 
-
-
 </section>
 
 ## Solution
 <section id='solution'>
 
-```js
-// solution required
+```html
+<link href="https://fonts.googleapis.com/css?family=Lobster" rel="stylesheet" type="text/css">
+<style>
+  .red-text {
+    color: red;
+  }
+
+  h2 {
+    font-family: Lobster, monospace;
+  }
+
+  p {
+    font-size: 16px;
+    font-family: monospace;
+  }
+
+  .smaller-image {
+    width: 100px;
+  }
+
+  .thick-green-border {
+    border-width: 10px;
+    border-color: green;
+    border-style: solid;
+  }
+</style>
+
+<h2 class="red-text">CatPhotoApp</h2>
+<main>
+  <p class="red-text">Click here to view more <a href="#">cat photos</a>.</p>
+
+  <a href="#"><img class="smaller-image thick-green-border" src="https://bit.ly/fcc-relaxing-cat" alt="A cute orange cat lying on its back."></a>
+
+  <div>
+    <p>Things cats love:</p>
+    <ul>
+      <li>cat nip</li>
+      <li>laser pointers</li>
+      <li>lasagna</li>
+    </ul>
+    <p>Top 3 things cats hate:</p>
+    <ol>
+      <li>flea treatment</li>
+      <li>thunder</li>
+      <li>other cats</li>
+    </ol>
+  </div>
+
+  <form action="/submit-cat-photo">
+    <label><input type="radio" name="indoor-outdoor" checked> Indoor</label>
+    <label><input type="radio" name="indoor-outdoor"> Outdoor</label><br>
+    <label><input type="checkbox" name="personality" checked> Loving</label>
+    <label><input type="checkbox" name="personality"> Lazy</label>
+    <label><input type="checkbox" name="personality"> Energetic</label><br>
+    <input type="text" placeholder="cat photo URL" required>
+    <button type="submit">Submit</button>
+  </form>
+</main>
 ```
+
 </section>