JSFiddle - React, Tailwind, and code Playground

HTML

<blockquote class="blockquote">
    <p>Цитата</p>
    <cite>Автор</cite>
</blockquote>

CSS

.blockquote {
    position: relative;
    text-align: center;
    margin: 16px 16px 34px 16px;
    border: 3px solid #337AB7;
    border-radius: 5px;
    padding: 2px 5px;
    font-size: 18px;
}
.blockquote:before,
.blockquote:after {
    content: '';
    position: absolute;
    width: 0;
    height: 0;
}
.blockquote:before {
    left: 30px;
    bottom: -32px;
    border: 16px solid;
    border-color: #337AB7 transparent transparent #337AB7;
}
.blockquote:after {
    left: 35px;
    bottom: -21px;
    border: 12px solid;
    border-color: #fff transparent transparent #fff;
}
.blockquote cite {
    position: absolute;
    bottom: -28px;
    left: 62px;
    font-size: 15px;
    font-weight: bold;
    color: #337AB7;
}