JSFiddle - React, Tailwind, and code Playground

HTML

<div class="wrap">
    <img src="http://placekitten.com/800/350" />
    <div class="arrowwrap">
        <div class="arrowone"></div>
    </div>
    <article>
        <h1>Hellow World, meow</h1>
    </article>
</div>

SCSS

body {
    background:#fad;
    padding:0;
    margin:0;
}

$arrow_width: 20px;
$arrow_height: 20px;
$box_color: #d3d030;

.wrap {
    img {
        width:100%;
        height:auto;
        vertical-align:bottom;
    }
    article {
        padding:20px;
        background:$box_color;
        color:#fff;
    }
}

.arrowwrap {
    width:100%;
    padding:0;
    position:relative;
    overflow:hidden;
    margin:-$arrow_height 0 0 0;
    &:after {
        content:'';
        position:absolute;
        height:$arrow_height;
        width:50%;
        margin:-$arrow_height 0 0 -$arrow_width;
        left:0;
        z-index:99999;
        background:$box_color;
    }
    &:before {
        content:'';
        position:absolute;
        height:$arrow_height;
        width:100%;
        left:50%;
        margin:0 0 0 $arrow_width;
        z-index:99999;
        background:$box_color;
    }
    .arrowone {
        width: 0;
        height: 0;
        border-style: solid;
        border-width: $arrow_height $arrow_width 0 $arrow_width;
        /* border-color: transparent transparent #333 transparent; */
        border-color:transparent $box_color $box_color $box_color;
        margin:auto;
    }
}