body{
    font-size: 16px;
}
*{
    box-sizing: border-box;
    }
.main{
    background: #d7d7d7;
    max-width: none;
    max-height: 600px;
    min-width: 800px;
    min-height: 400px;
    box-sizing: border-box;
    border-top-left-radius: 50px;
    border-bottom-left-radius: 50px ;
    overflow: auto;
    border: 1px solid #000;
}

.sub {
    background: #bcae72;
    width: 300px;
    height: 250px;
    padding: 30px  30px;
    margin: 10px 5px;
    box-sizing: border-box;
    box-shadow: inset 0 0 10px;
    border-radius: 40px;
    display: inline-block;
}