Hero image white space

Hello as seen on https://www.drphysio.gr/test-hero-images/ on mobile view there is white space on the sides.
How to make it fully stretched?
I use iphone 4s for testing.
Tried the layouts fully stretched and padded
Thank you in advance!

Hello there,

Try adding this CSS code to Appearance > Customize > Additional CSS from dashboard.

    @media only screen and (max-width: 780px) {
      #pgc-42703-0-0.panel-grid-cell {
        padding: 0 !important;