JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
    <div></div>
    <div></div>
    <div></div>
    <div></div>
</div>
<div class="container">
    <div></div>
    <div class="two"></div>
    <div></div>
</div>
<div class="container">
    <div class="two"></div>
    <div></div>
    <div></div>
</div>
<div class="container">
    <div></div>
    <div></div>
    <div class="two"></div>
</div>
<div class="container">
    <div class="three"></div>
    <div></div>
</div>
<div class="container">
    <div></div>
    <div class="three"></div>
</div>

CSS

div.container
{
    display: flex;
    margin-bottom: 10px;
}

div.container > div
{
    flex: 1 1 5em;
    margin-left: 10px;
    height:50px;
    background-color: blue;
}

div.container > div:first-child
{
    margin-left: 0;
}

div.container > div.two
{
    flex:2 2 calc(10em + 10px); /** 10px is the missing margin of the missing box */
}

div.container > div.three
{
    flex:3 3 calc(15em + 20px); /** 20px is the missing margin of the two missing boxes */
}