How to resize blog image on Simple theme?

[VcentG]

Hello, I've been using the basic Simple theme for a while now. I started to write blog posts and I noticed when viewing them the picture was MASSIVE. I edited the code a bit with some googling and what not and made the image smaller. But the actual SPACE for the image is still there. Also I've gone so far down the rabbit hole I don't know what the original code was. All I want is the image to be smaller.

Carnivorous Plant Care Guides – Carnivorous Greenhouse here's the link to my page so you can see the issue.

I edited this area in Assets/theme.scss.liquid to make it change, but honestly I thought I removed everything I added but the picture is still tiny... which is fine if I could just get the space to go away.

.article__image-wrapper {
  display: block;
  position: relative;
}

.article__image {
  display: block;
  margin-bottom: $gutter / 2;
  .supports-js & {
    position: absolute;
    top: 0;
  }

  &.lazyload {
    opacity: 0;

[VcentG]

I added more blogs, so to see the problem is actually on page 2 of the blogs:
Guides Page 2 

I would like to add pictures for all of them but I don't want these massive page loading gaps.

[KetanKumar]

@VcentG 

oh sorry but i can't see any blog image how can i check this 

[VcentG]

There seems to be no edit option, so i posted a reply with the link to page 2 of the blogs. The two at the bottom have images. I also wish I could post pictures here but it only accepts weird file types.

[KetanKumar]

@VcentG 

where did you added image?

[VcentG]

As you can see here, the image space is huge. I got the picture to be smaller but it still uses up the same amount of space.