SOURCE

<div class="container1 ct">
  <div class="flb flbox1">box1</div>
  <div class="flb flbox2">box2</div>
  <div class="flb flbox3">box3</div>
</div>


<div class="container2 ct">
  <div class="flb flbox1">box1</div>
  <div class="flb flbox2">box2</div>
  <div class="flb flbox3">box3</div>
</div>

<div class="container3 ct">
  <div class="flb flbox1">box1</div>
  <div class="flb flbox2">box2</div>
  <div class="flb flbox3">box3</div>
</div>

<div class="container4 ct">
  <div class="flb flbox1">box1</div>
  <div class="flb flbox2">box2</div>
  <div class="flb flbox3">box3</div>
</div>

.ct {
 overflow: hidden;
}
.ct + .ct {
  margin-top: 20px;
}
.flb {
  float: left;
  width: 100px;
  height: 100px;
}
.flbox1{background-color: rgba(33, 114, 214, 0.8);}
.flbox2{background-color: rgba(255, 82, 0, 0.8);}
.flbox3{background-color: rgba(90, 243, 151, 0.8);}


.container2 .flb {
  margin-left: -25px;
}

.container3 .flb {
  margin-left: -50px;
}

.container4 .flbox3 {
  margin-left: -200px;
}