diff --git a/firebird-ng/src/app/app.component.html b/firebird-ng/src/app/app.component.html
index 8bd483f..e6dbb44 100644
--- a/firebird-ng/src/app/app.component.html
+++ b/firebird-ng/src/app/app.component.html
@@ -1,4 +1,4 @@
-<nav class="navbar navbar-expand-lg navbar-dark" style="background-color: #424242;">
+<nav class="  navbar navbar-expand-lg navbar-dark" style="background-color: #424242;">
   <a class="navbar-brand" href="#"><img src="assets/firebird/firebird-simplified-circle.png" width="32" height="32" alt="App Logo"></a>
   <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNavDropdown" aria-controls="navbarNavDropdown" aria-expanded="false" aria-label="Toggle navigation">
     <span class="navbar-toggler-icon"></span>
diff --git a/firebird-ng/src/app/main-display/main-display.component.html b/firebird-ng/src/app/main-display/main-display.component.html
index e794980..3f31819 100644
--- a/firebird-ng/src/app/main-display/main-display.component.html
+++ b/firebird-ng/src/app/main-display/main-display.component.html
@@ -90,6 +90,10 @@
   <button mat-raised-button aria-label="Play"  matTooltip="Play time forward" class="tcontrol" (click)="animateTime()">
     <mat-icon>play_arrow</mat-icon>
   </button>
+  <button mat-raised-button aria-label="Step" matTooltip="Step 1ns backward" (click)="timeStepBack($event)" class="tcontrol">
+    <mat-icon>chevron_left</mat-icon>
+  </button>
+
   <button mat-raised-button aria-label="Step" matTooltip="Step 1ns forward" (click)="timeStep($event)" class="tcontrol">
     <mat-icon>chevron_right</mat-icon>
   </button>
diff --git a/firebird-ng/src/app/main-display/main-display.component.ts b/firebird-ng/src/app/main-display/main-display.component.ts
index a42a70e..a5fcec1 100644
--- a/firebird-ng/src/app/main-display/main-display.component.ts
+++ b/firebird-ng/src/app/main-display/main-display.component.ts
@@ -649,6 +649,11 @@ export class MainDisplayComponent implements OnInit {
 
     //this.updateParticlePosition(value);
   }
+  timeStepBack($event: MouseEvent) {
+    if(this.currentTime > this.minTime) this.currentTime--;
+    if(this.currentTime < this.minTime) this.currentTime = this.minTime;
+    this.processCurrentTimeChange();
+  }
 
   timeStep($event: MouseEvent) {
     if(this.currentTime < this.maxTime) this.currentTime++;