Change Navigation Stack columns dimensions

Hi. I'm writing the following code for a navigation with images and I have an issue: the images don't fit with the automatic rectangle that is created by the NavigationStack view. Here is the code and I'm attaching an image too for you to understand :

import SwiftUI

struct LycéesListe: View {
    var body: some View {
        NavigationStack {
            List(lycées) { lycée in
                NavigationLink {
                    LycéeDétail(lycée: lycée)
                } label: {
                    LycéesRow(lycée: lycée)
                }
        }
        .navigationTitle("Lycées")
    }
}

    
    struct LycéesListe_Previews: PreviewProvider {
        static var previews: some View {
            ForEach(["iPhone 13", "iPhone 12"], id: \.self) { deviceName in LycéesListe()
                    .previewDevice(PreviewDevice(rawValue: deviceName))
                    .previewDisplayName(deviceName)
            }
        }
    }
}

Anyone knows how I could make the images fit with the rectangle border so I just have images with clean rectangles and not these green lines ? I tried to do padding but it didn't help. Any answer appreciated.