Tweak timesheet styles, to give rows alternating background color

tailbone/static/css/timesheet.css

@@ -4,6 +4,7 @@
  **********************************************************************/
 
 .timesheet-header {
+    overflow: auto;
     position: relative;
 }
 
@@ -29,6 +30,14 @@
     border-top: 1px solid black;
 }
 
+.timesheet tbody {
+    background-color: white;
+}
+
+.timesheet tbody tr:nth-child(odd) {
+    background-color: #e0e0e0;
+}
+
 .timesheet tbody td {
     padding: 5px;
     text-align: center;