<div class="kapsayici">
  <div>minmax uygulanan</div>
  <div>diğer kutu</div>
  <div>diğer kutu</div>
</div>
.kapsayici {
  display: grid;
  grid-template-columns: minmax(80px, 240px) 100px 100px;
  grid-gap: 10px;
  width: 100%;
}

div > div {
  border:2px solid #006c8e;
  background: #009cc1;
  padding: 5px;
  font-family: arial;
  color: white;
  font-size: 18px
}

body {
  margin:20px;
  border-right: 3px solid #006c8e;
}

External CSS

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External JavaScript

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