How can I make my own header

Hi I know there is a header option in “Navigation” but I am looking to make my own header. I was wondering on a page. If I add a container how can I make it stay on a page depending on the size. By example, if I have a mobile that is a certain size wide well the container would be from one end of the screen to the other end. If I have an ipad same thing the header would be the full length of the screen. Look at the image below. The header has an orange ish header with text and a go back arrow.

Yes! There are plenty of people who have done their own navigation header bar. I cover it quickly here although I don’t go into making the back button much, that could get you started probably :slight_smile: