ironbar: Add notifications module

This seems to work good enough for now, but the icon won't be
immediately updated.

home/ironbar.nix

@@ -57,6 +57,9 @@ in
         type = "clock";
         format = "%x（%a）%R";
       }
+      {
+        type = "notifications";
+      }
     ];
   };
 
@@ -90,6 +93,11 @@ in
       padding-right: 0.5em;
     }
 
+    .notifications button {
+      padding-left: 0.2em;
+      padding-right: 0.7em;
+    }
+
     slider {
       background: #${base0D};
     }
@@ -113,6 +121,10 @@ in
       padding: 1em;
     }
 
+    .clock {
+      padding-right: 0.4em;
+    }
+
     .popup-clock .calendar-clock {
       font-family: "Maple Mono";
       font-size: 2.5em;