JSFiddle - React, Tailwind, and code Playground

HTML

<div class="gallery-top">
  <div class="fl col1">
    <div class="inner">
      <img src="https://placeholdit.imgix.net/~text?txtsize=15&txt=150%C3%9780&w=150&h=80" />
    </div>
    <div class="inner">
      <img src="https://placeholdit.imgix.net/~text?txtsize=15&txt=150%C3%9780&w=150&h=80" />
    </div>
    <div class="cb"></div>
  </div>
  <div class="fl col2">
    <div class="inner">
      <img src="https://placeholdit.imgix.net/~text?txtsize=15&txt=150%C3%9780&w=150&h=80" />
    </div>
    <div class="inner">
      <img src="https://placeholdit.imgix.net/~text?txtsize=15&txt=150%C3%9780&w=150&h=80" />
    </div>
    <div class="cb"></div>
  </div>
  <div class="cb"></div>
</div>

CSS

img {
  width: 100%;
  max-width: 100%;
}

.gallery-top {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
}

.gallery-top div {
  width: 49.8%;
}

.gallery-top div .inner {
  width: 100%;
}