Check out example codes for "css flex property". It will help you in understanding the concepts better.

Code Example 1

/* use this if you want to center stuff like in your div */
.flexbox_card {
        display: flex;
        flex-wrap: wrap;
        justify-content: center;
    }

Code Example 2

flex: none | [ <'flex-grow'> <'flex-shrink'>? || <'flex-basis'> ]

Code Example 3

The flex CSS property sets how a flex item will grow or shrink to fit the space
available in its flex container. It is a shorthand for flex-grow , flex-shrink ,
and flex-basis .

Code Example 4

<div class="flex-container">
  <div>1</div>
  <div>2</div>
  <div>3</div>
</div>
<style>
  .flex-container {
  display: flex; // default: flow
  flex-direction: column; // elements in a column
}
</style>

Code Example 5

/* Flex */
.anyclass {
	display:flex;
}
/* row is the Default, if you want to change choose */
.anyclass {
	display:flex;
 	flex-direction: row | row-reverse | column | column-reverse;
}

.anyclass {
  /* Alignment along the main axis */
  justify-content: flex-start | flex-end | center | space-between | space-around | space-evenly | start | end | left | right ... + safe | unsafe;
}

Code Example 6

flex: none                                            /* value 'none' case */
flex: <'flex-grow'>                                   /* One value syntax, variation 1 */
flex: <'flex-basis'>                                  /* One value syntax, variation 2 */
flex: <'flex-grow'> <'flex-basis'>                    /* Two values syntax, variation 1 */
flex: <'flex-grow'> <'flex-shrink'>                   /* Two values syntax, variation 2 */
flex: <'flex-grow'> <'flex-shrink'> <'flex-basis'>    /* Three values syntax */
flex: inherit

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