SOURCE

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div{
    width: 300px;
    height: auto;
    max-height: 400px;
    background: #ccc;
    overflow: hidden;
    position: relative;
}

span{
    display: inline-block;
    width: 50px;
    height: 40px;
    margin: 5px 8px;
    background: red;
}

div:after{
    content: "^";
    width: 40px;
    height: 40px;
    position: absolute;
    top: 340px;
    right: 30px;
    background: white;
    line-height: 40px;
    text-align: center;
    border-radius: 40px;
}