Stretch image in iron-image element

Question

I have an element inside a div :

. The image is 315px in width

Answer 1

I had the same problem, the sizing attribute doesn't help me for that, and because the img inside iron-image is under shady DOM, you can access it with ::content.

#imgWrapper {
    width: 330px;
}
iron-image {
    width:100%;
}
iron-image::content img {
    width: 100%;
}

and

for ::content to work in light dom (outside of a custom element) don't forget