Add collaboration stylesheet for light theme

src/packages/collaboration/stylesheets/collaboration.less

@@ -1,14 +1,13 @@
 @import "bootstrap/less/variables.less";
 @import "octicon-mixins.less";
-@runningColor: #99CC99;
 
 .collaboration {
   @item-line-height: @line-height-base * 1.25;
   padding: 10px;
   -webkit-user-select: none;
-  cursor: pointer;
 
   .share {
+    cursor: pointer;
     .mini-icon(notifications);
     position: relative;
     right: -1px;
@@ -20,15 +19,6 @@
     position: relative;
     right: -2px;
     margin-bottom: 5px;
-    color: #96CBFE;
-  }
-
-  .running {
-    color: @runningColor;
-
-    &:hover {
-      color: lighten(@runningColor, 15%);
-    }
   }
 
   .avatar {

themes/atom-dark-ui/collaboration.less

@@ -1,3 +1,5 @@
+@runningColor: #99CC99;
+
 .collaboration {
   background: #1b1c1e;
   box-shadow:
@@ -5,4 +7,16 @@
     inset -1px 0 0 rgba(255, 255, 255, 0.02),
     1px 0 3px rgba(0, 0, 0, 0.2);
   color: #cecece;
+
+  .guest {
+    color: #96CBFE;
+  }
+
+  .running {
+    color: @runningColor;
+
+    &:hover {
+      color: lighten(@runningColor, 15%);
+    }
+  }
 }

themes/atom-light-ui/collaboration.less

@@ -0,0 +1,18 @@
+@runningColor: #f78a46;
+
+.collaboration {
+  background: #dde3e8;
+  border-left: 1px solid #989898;
+
+  .guest {
+    color: #5293d8;
+  }
+
+  .running {
+    color: @runningColor;
+
+    &:hover {
+      color: darken(@runningColor, 10%);
+    }
+  }
+}

themes/atom-light-ui/package.cson

@@ -11,4 +11,5 @@
   'blurred'
   'image-view'
   'archive-view'
+  'collaboration'
 ]