<div class="kapsayici">
  <div class="ust-alan">Üst Alan</div>
  <div class="menu">Menü</div>
  <div class="baner">Baner</div>
  <div class="icerik">İçerik</div>
  <div class="alt-alan">Alt Alan</div>
</div>
.kapsayici {
  width: 400px;
  height: 100%;
  margin: 0 auto;
  display: grid;
  grid-template: 
            "menu ust ust" 4ch
            "menu icerik icerik" auto
            "baner alt alt" 4em / 20% 20px 1fr;
}

.kapsayici div {
  padding: 5px;
}

.ust-alan {
  background: yellow;
  grid-area: ust;
}

.baner {
  background: hotpink;
  grid-area: baner;
}

.menu {
  background: mistyrose;
  grid-area: menu;
}

.icerik {
  background: deepskyblue;
  grid-area: icerik;
}

.alt-alan {
  background: springgreen;
  grid-area: alt;
}

html, body {
  height: 100%;
  margin: 0;
  padding: 0;
}

External CSS

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External JavaScript

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