Put output outside of container and max-width for it to use the full width of the page.

index.php

@@ -58,14 +58,16 @@ if(isset($_POST['input']) && isset($_POST['type'])) {
             <input type="submit" class="btn btn-primary btn-lg" value="Hash">
 
 		</form>
+    </div>
+</div>
 
-		<?php
-		if(isset($hash) && $hash != null) {
-		    echo "<br><br><br><br><h5>Output</h5>";
-			echo $hash;
-		}
-		?>
-	</div>
+<div style="margin-left: auto; margin-right: auto; text-align: center;" class="mt-5">
+	<?php
+	if(isset($hash) && $hash != null) {
+		echo "<br><br><br><br><h5>Output</h5>";
+		echo $hash;
+	}
+	?>
 </div>
 
 <div style="height: 120px;"></div>