SOURCE

<div class="container">
    <div class="box"></div>
    <div class="blackbox"></div>
</div>

html,body.container{
            width: 100%;
            height: 100%;
            background: white;
        }
        .box{
            width: 60px;
            height: 200px;
            margin: 300px auto;
            background: linear-gradient( 135deg, rgb(16, 114, 243) 0, rgb(16, 114, 243) 25%, transparent 25%, transparent 50%,
                rgb(16, 114, 243) 50%, rgb(16, 114, 243) 75%, transparent 75%, transparent);
            background-size: 50px 50px;
        }
        .blackbox{
            width: 100%;
            height: 300px;
            background: radial-gradient(
                rgb(16, 114, 243) 0, cyan 25%, cyan 25%, transparent 50%,
                cyan 50%, transparent 75%, cyan 75%, rgb(16, 114, 243)
            );
            background-size: 120px 120px;
        }