css ol

Title 
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        *{margin: 0; padding: 0}
        .content{width: 1200px; height: 700px; border: 1px blue solid; margin: 0 auto;}
        .min{
            width: 100px; height: inherit;background: red;position: absolute;
            left: 1250px;
            transition: left;
            transition-duration: 3s;
        }
        .content:hover .min{
            left: 0;
        }
    </style>
</head>
<body>
    <div class="content">
        <div class="min"></div>
    </div>
</body>
<html>