<div class="box_uno">uno</div>
<div class="box_dos">dos</div>
<div class="box_tres">tres</div>
<div class="box_cuatro">cuatro</div>
$ancho: 720px;
$blue: #4285F4;
$green: #33D374;

.box_uno {
  background-color: $blue;
  width: $ancho/2;
}
.box_dos {
  background-color: $green;
  width: ($ancho/2)-50;
}
.box_tres {
  background-color: $blue;
  width: ($ancho/2)+50;
}
.box_cuatro {
  background-color: $green;
  width: ($ancho/7)*2;
}

External CSS

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External JavaScript

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