JSFiddle - React, Tailwind, and code Playground

by Alexey Lisovy

HTML

<button>Кнопка</button>

CSS

body
        {
            height: 100vh;
            display: flex;
        }
button
        {
            padding: 6px 25px;
            font-size: 1.5em;
            background-color: #1D7BC5;
            color: #fff;
            position: relative;
            box-sizing: border-box;
            border: none;
            border-top: 1px solid #ccc;
            border-left: 1px solid #ccc;
#           display: inline-block;
#           outline: none;
            margin: auto;
            font-family: Roboto;
            font-weight: 300;
         }
button::before, button::after
         {
            content: '';
            position: absolute;
            background-color: #1D7BC5;
            box-sizing: border-box;
            z-index: -1;           
         }

button::before
         {
            width: 10px;
            height: 100%;
            right: 100%;
            top: 0;
            transform: skewY(45deg);
            transform-origin: 100% 0;
         }
button::after
         {
            width: 100%;
            bottom: 100%;
            height: 10px;
            left: 0;
            transform: skewX(45deg);
            transform-origin: 0 100%;
            border-left: 1px solid #ccc;
         }