Add more Blinka info

Also add API link at the top.

_includes/header.html

@@ -7,6 +7,7 @@
         <a href="https://blog.adafruit.com/category/circuitpython">News</a>
         <a {% if current[1] == 'awesome' %}class='active'{% endif %} href="{{ "/awesome" | relative_url  }}">Awesome</a>
         <a href="https://www.adafruitdaily.com/category/circuitpython">Newsletter</a>
+        <a href="https://circuitpython.readthedocs.io/">API</a>
         <a href="https://forums.adafruit.com/viewforum.php?f=60">Help</a>
         <span>
             <a href="https://adafru.it/discord"><i class="fab fa-discord"></i></a>

blinka.html

@@ -6,6 +6,9 @@ permalink: /blinka
 
 <div id="downloads-page">
   <h1>Blinka</h1>
+  <p>
+    Blinka brings CircuitPython APIs and, therefore, libraries to single board computers (SBCs). It is a <a href="https://pypi.org/project/Adafruit-Blinka/">pip installable Python library</a> that runs in normal "desktop" Python. The CircuitPython runtime isn't used. <a href="https://pypi.org/search/?q=adafruit-circuitpython">Libraries</a> can also be installed via pip. See <a href="https://learn.adafruit.com/circuitpython-on-raspberrypi-linux"> the guide</a> for further details.
+  </p>
   <div class="downloads-inputs">
     <div class="downloads-search">
       <label class="search-wrapper">

index.html

@@ -127,6 +127,36 @@ layout: home
     </section>
   </div>
 
+  <div class="headline-banner supported-section">
+      <!-- TODO: Replace this image with a picture of many sensor boards. -->
+    <img class="image-headline pinball" alt="hero image"
+                                src="{{ "assets/images/CircuitPython_Pinball.jpg" |
+                                relative_url }}"
+         />
+    <div class="text">
+      <div class="title"><span>280+ libraries all written in Python</span></div>
+    </div>
+  </div>
+
+  <div class="content">
+    <section>
+      <!-- TODO: Replace this image with a raspberry pi image. -->
+      <img class="responsive" src="{{ "/assets/images/python.png" | relative_url }}"
+           srcset="{{ "/assets/images/python.png" | relative_url }} 1x,
+                   {{ "/assets/images/python@2x.png" | relative_url }} 2x,
+                   {{ "/assets/images/python@3x.png" | relative_url }} 3x"  alt="Python Logo">
+      <h2>CircuitPython libraries on single board computers</h2>
+      <p>
+        Most CircuitPython libraries also work on <a href="/blinka">single board computers (SBCs)</a>, such as the Raspberry Pi.
+        Linux runs "desktop" Python (commonly known as CPython) instead of CircuitPython.
+        Our CPython Blinka library provides CircuitPython's low level hardware APIs, such as `digitalio`. 
+      </p>
+      <p>
+        Blinka and CircuitPython libraries are just a `pip install` away.
+      </p>
+    </section>
+  </div>
+
   <div class="purple banner">
     <div class="content short">
     <h2>Just the beginning...</h2>