Generated by SassMeister.com.

SassMeister-input-HTML.html

<div class="one">
  <span>
  <img src="https://pbs.twimg.com/profile_images/509056962277818368/w8lt2OuI.jpeg">
  </span>
  abc
</div>
<div class="two">
  <img src="https://pbs.twimg.com/profile_images/509056962277818368/w8lt2OuI.jpeg">
  abc
</div>
<div class="three">
 <img src="https://pbs.twimg.com/profile_images/509056962277818368/w8lt2OuI.jpeg">
  abc
</div>

SassMeister-input.scss

// ----
// Sass (v3.3.14)
// Compass (v1.0.1)
// Susy (v2.1.3)
// ----

@import "susy";
* {
  box-sizing: border-box;
}
$susy: (columns: 12);

div {
  background: #eee;
  padding: gutter(); // 1.69% means 26px
  @include span(4); 
  &.three {
    @include span(last 4);
  }
  span {
    display: block;
    background: green;
    @include bleed(gutter()); // 1.69% means 7.5px
    margin-bottom: 10px;
  }
  img {
    max-width: 100%;
    height: auto;
  }
}

SassMeister-output.css

* {
  box-sizing: border-box;
}

div {
  background: #eee;
  padding: 1.69492%;
  width: 32.20339%;
  float: left;
  margin-right: 1.69492%;
}
div.three {
  width: 32.20339%;
  float: right;
  margin-right: 0;
}
div span {
  display: block;
  background: green;
  margin: -1.69492%;
  padding: 1.69492%;
  margin-bottom: 10px;
}
div img {
  max-width: 100%;
  height: auto;
}

SassMeister-rendered.html

<div class="one">
  <span>
  <img src="https://pbs.twimg.com/profile_images/509056962277818368/w8lt2OuI.jpeg">
  </span>
  abc
</div>
<div class="two">
  <img src="https://pbs.twimg.com/profile_images/509056962277818368/w8lt2OuI.jpeg">
  abc
</div>
<div class="three">
 <img src="https://pbs.twimg.com/profile_images/509056962277818368/w8lt2OuI.jpeg">
  abc
</div>