<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
</head>
<body>
<style>
html, body {
height: 100%;
}
.main {
border: 1px solid black;
width: 200px;
height: 100%;
}
.div-1{
background: lime;
height: 100px;
border-bottom: 2px solid white;
}
.div-2 {
background: red;
width: 100%;
height: auto;
}
.ads {
width: 180px;
height: 180px;
margin: 0 auto;
background: blue;
}
</style>
<div class="main">
<div class="div-1"></div>
<div class="div-1"></div>
<div class="div-1"></div>
<div class="div-2">
<div class="ads"></div>
</div>
</div>
</body>
</html>
Простой
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Простой
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