Style tweaks

- Font change to Roboto
- Slightly off-white background
- Dark circle around the logo image
diff --git a/static/css/style.scss b/static/css/style.scss
index 23b80ff..37bdbc6 100644
--- a/static/css/style.scss
+++ b/static/css/style.scss
@@ -5,6 +5,7 @@
 $light-grey: #eeeeee;
 $med-grey: #5f5f5f;
 $dark-grey: #202020;
+$bg-grey: #FAFAFA;
 
 $code-border: #c7c7c7;
 $code-background: #f6f6f6;
@@ -13,9 +14,9 @@
 $blue: #0e94ec;
 $accent: $blue;
 
-@import url("https://fonts.googleapis.com/css?family=Ubuntu|Ubuntu+Mono");
-$sans: 'Ubuntu', sans-serif;
-$mono: 'Ubuntu Mono', monospace;
+@import url(https://fonts.googleapis.com/css?family=Roboto|Roboto+Mono);
+$sans: 'Roboto', sans-serif;
+$mono: 'Roboto Mono';
 
 $border_color: #c2c2c2;
 $pag_label_size: 60px;
@@ -30,7 +31,7 @@
 body {
   margin: 0;
   padding: 0;
-  background-color: $white;
+  background-color: $bg-grey;
   color: $dark-grey;
   font-family: $sans;
   font-size: 16px;
@@ -67,6 +68,9 @@
         width: $logo_size;
         height: $logo_size;
         border-radius: 50%;
+        border: 5px solid $black;
+        background-color: $black;
+        box-shadow: 0px 0px 1px $black;
     }
 
     h2 {