meta: add OG image

public/index.html

@@ -18,7 +18,7 @@
       itemprop="description"
       content="A flexible icon family for interfaces, diagrams, presentations — whatever, really."
     />
-    <meta itemprop="image" content="https://phosphoricons.com/promo.jpg" />
+    <meta itemprop="image" content="https://phosphoricons.com/phosphor-opengraph.png" />
 
     <!-- FACEBOOK META -->
     <meta property="og:title" content="Phosphor Icons" />
@@ -29,11 +29,11 @@
     />
     <meta property="og:type" content="website" />
     <meta property="og:url" content="https://phosphoricons.com" />
-    <meta property="og:image" content="https://phosphoricons.com/promo.jpg" />
-    <meta property="og:image:type" content="image/jpeg" />
+    <meta property="og:image" content="https://phosphoricons.com/phosphor-opengraph.png" />
+    <meta property="og:image:type" content="image/png" />
     <meta property="og:image:alt" content="Phosphor Icons logo" />
-    <meta property="og:image:width" content="960" />
-    <meta property="og:image:height" content="590" />
+    <meta property="og:image:width" content="1200" />
+    <meta property="og:image:height" content="630" />
 
     <!-- TWITTER META -->
     <meta name="twitter:card" content="summary_large_image" />
@@ -42,7 +42,7 @@
       name="twitter:description"
       content="A flexible icon family for interfaces, diagrams, presentations — whatever, really."
     />
-    <meta name="twitter:image" content="https://phosphoricons.com/promo.jpg" />
+    <meta name="twitter:image" content="https://phosphoricons.com/phosphor-opengraph.png" />
     <meta name="twitter:site" content="@_phosphoricons" />
     <meta name="twitter:creator" content="@friedtm" />