CSS : Align items in flex layout

Question

I want the down arrow to be in the bottom centre of the page. I am trying to achieve this through flex layout. but unable to do it so far. Can someone please help me ? Below is my css /html

.flex-description-container {
  display: flex;
  flex-flow: row wrap;
  align-items: center
}

.flex-item-descriptionText {
  padding: 10px;
  color: white;
  font-weight: bold;
  font-size: 4em;
  text-align: center;
  flex: 1;
}

.flex-item-descriptionImage {
  padding: 10px;
  color: white;
  flex: 1;
}

.flex-item-next {
  flex: 1 100%;
  align-items: center;
  align-self: flex-end;
  justify-content: center;
}

App.jsx>

<Parallax.Layer
                    offset={0} speed={0}
                    onClick={() => this.parallax.scrollTo(1)}>
                    <div class="flex-description-container ">
                        <div class="flex-item-descriptionText">Text </div>
                        <div class="flex-item-descriptionImage">
                            <img src={url('desk')} style={{ width: '50%' }} />
                        </div>
                        <div class="flex-item-next">
                            <img src={url('down')} style={{ width: '5%' }} />
                        </div>
                    </div>
                </Parallax.Layer>

PS: I am using this react component

Answer 1

Just add display:flex to .flex-item-next .

.flex-item-next {
  flex: 1 100%;
  display: flex;
  align-items: center;
  align-self: flex-end;
  justify-content: center;
}

See working implementation .

Answer 2

for do that enter this code to .flex-item-next :

.flex-item-next {

  display: flex;

  flex: 1 100%;
  align-items: center;
  align-self: flex-end;
  justify-content: center;

}