Image displays only when height is set to length

When developing a WordPress theme I encountered this issue. I posted this question in WordPress stack exchange but received no answers.

I have a 2 column layout one column is in text & some images second is an image. In mobile view, they stack on each other but the image appears only when the height of (.column__two { width: 100%; height : 300px; }) is set to length. If set to auto or percent etc it does not display the image.

So why is this happening?

The code is below: In front-page.php

<div class="container__one">
    <div class="column__one">
        <h1><?php echo get_theme_mod('showcase_1_heading', 'Default heading') ?></h1>
        <p><?php echo get_theme_mod('showcase_1_text', 'Default paragraph') ?></p>
        <div class="three_images">
            <div class="img__1">
                <img src="<?php echo get_theme_mod('small_image1', get_bloginfo('template_url') . '/img/lunch-1.jpg'); ?>" alt="lunch image">
                <p><?php echo get_theme_mod('showcase_1img1_text', 'Default paragraph') ?></p>
            </div>
            <div class="img__2">
                <img src="<?php echo get_theme_mod('small_image2', get_bloginfo('template_url') . '/img/lunch-2.jpg'); ?>" alt="lunch image">
                <p><?php echo get_theme_mod('showcase_2img2_text', 'Default paragraph') ?></p>
            </div>
            <div class="img__3">
                <img src="<?php echo get_theme_mod('small_image3', get_bloginfo('template_url') . '/img/lunch-3.jpg'); ?>" alt="lunch image">
                <p><?php echo get_theme_mod('showcase_3img3_text', 'Default paragraph') ?></p>
            </div>
        </div>
        <a href="<?php echo get_theme_mod('btn_url', 'www.test.com') ?>"><?php echo get_theme_mod('btn_text') ?></a>
    </div>

    <div class="column__two">
        <style>
            .column__two {
                background: url(<?php echo get_theme_mod('showcase_2_image', get_bloginfo('template_url') . '/img/showcase.jpg'); ?>) no-repeat center center;
                background-size: cover;
            }
        </style>
    </div>

In style.css

.container__one {
    display: flex;
    flex-wrap: wrap;
    flex-direction: row;
    /* align-content: space-around; */
    margin: auto;
    max-width: 960px;
    height: fit-content;
    }

.column__one {
    background-color: grey;
    width: 100%;
    height: fit-content;
}

.column__two {
    width: 100%;
    height: 300px; /*The issue is in this line */
}

@media all and (min-width: 600px) {
    .column__one {
        width: 50%;
        height: fit-content;
    }
    .column__two {
        width: 50%;
        height: auto;
    }
}

Hey @FakhriAz

Is this up on a server someplace where we could see it in dev tools?

@rickstewart,
I did not understand your question well. I copied the code from my text editor not Dev Tools.

As you can see there is some PHP code.

Sorry for not being more clear. I was asking if the website with the issue was available to be viewed online so that we can examine it?

Thank you for your quick answer and support, unfortunately it is being developed on a local machine using XAMPP.

I was able to fix the issue by testing but I did not understand why exactly. I did a lot of Googling but in vain.