<!doctype html>
<html>
<head>
<style>
#container {
height: 300px;
width: 300px;
overflow:hidden;
border-radius:30px;
}
#inner {
width: 380px;
height: 260px;
background-color: #7fff7f;
</style>
</head>
<body>
<div id="container">
<div id="inner">
</div>
</body>
</html>