[timeline] line time indicators

app/src/plugins/app@vendor/vue-cal/styles.scss

@@ -178,8 +178,8 @@ $splits-headers-height: 1.5em;
     .vuecal__time-cell {
       color: #999;
       text-align: right;
-      padding-right: 2px;
       font-size: 0.9em;
+      background: white;
     }
 
     .vuecal__time-cell-line:before {
@@ -187,7 +187,12 @@ $splits-headers-height: 1.5em;
       position: absolute;
       left: 0;
       right: 0;
-      border-top: 1px solid rgba(196, 196, 196, 0.3);
+      border-top: 1px solid #F5F5F5;
+      z-index: -1;
+    }
+    
+    .vuecal__time-cell-line.hour:before {
+      border-top: 1px solid #e0e0e0;
     }
   }