JSFiddle - React, Tailwind, and code Playground

HTML

<article class="home-post-container">
    <div class="home-post-thumb">POST THUMBNAIL</div>
    <div class="home-post-content">
        <h4 class="post-title">POST TITLE</h4>
        POST CONTENT
    </div>
</article>

CSS

.home-post-container {
    display: flex;
    padding: 1vw;
}

.home-post-thumb {
    flex: 1;
    margin: auto;
    border: 1px solid red;
}
.home-post-content {
    flex:3;
    border: 1px solid red;
}

@media (max-width: 400px) {
    .home-post-container {
        flex-direction: column;
        
    }
}