CodePen

HTML

            
              <div class="boxes">
  <div class="box big"></div>
  <div class="box"></div>
  <div class="box"></div>
  <div class="box"></div>
  <div class="box"></div>
</div>
            
          
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CSS

            
              * {
  box-sizing: border-box;
}

.boxes {
  max-width: 1600px;
  min-width: 1100px;
}

.box {
  width: 25%;
  padding-bottom:25%;
  background: #ccc;
  float: left;
  background-position: center center;
  background-repeat: no-repeat;
  
  background-image: url('http://placebear.com/500/500');
}

.box.big {
  width: 50%;
  padding-bottom: 50%;
  background: #999;
  
  background-image: url('http://placebear.com/g/1000/1000');
}
            
          
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JS

            
              
            
          
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