.polka-container {
    width:280px;
    height: 480px;
}
.polka {
    width:150px;
    height:150px;
    background-image: radial-gradient(black 2px, transparent 2px);
    background-size: 6px 6px;
    position: relative;
    &.b{
        top: -60px;
        left: 70px;
        transform: rotate(14deg);
    }
    &.c{
        top: -80px;
        left: 100px;
        transform: rotate(45deg);
    }
    &.d{
        left: 130px;
        top: -120px;
    }
}

<div class="polka-container">
    <div class="polka a"></div>
    <div class="polka b"></div>
    <div class="polka c"></div>
    <div class="polka d"></div>
</div>