Почему флекс-элементы не отображаются в ряд?

.container {
  max-width: 1180px;
  margin: 0px auto;
}

.columns {
  background-color: #f5f5f5;
  padding: 50px 0 20px 0;
}

.columns__title {
  text-align: center;
  margin-bottom: 30px;
}

.columns__row {
  display: flex;
  margin: 0px -8px;
}

.columns__column {
  flex: 0 1 50%;
  margin: 0 0 30px 0;
  padding: 0px 8px;
}

.columns__item {}

.item {}

.item__row {
  display: flex;
}

.item__image {
  flex: 0 0 200px;
}

.item__body {
  flex: 1 1 auto;
  padding-left: 15px;
}

.item__title {
  color: #445161;
  font-size: 24px;
  line-height: 30px;
  margin-bottom: 13px;
}

.item__text {
  color: #333333;
  font-size: 16px;
  line-height: 24px;
}

<div class="columns">
  <div class="container">
    <div class="columns__title title">Columns</div>
    <div class="columns__row">
      <div class="columns__column">
        <div class="columns__item item">
          <div class="item__row">
            <div class="item__image">
              <img src="..//myproject/img-flex/image_3.jpg" alt="">
            </div>
            <div class="item__body">
              <div class="item__title">The description for the image</div>
              <div class="item__text">Lorem ipsum dolor sit amet consectetur adipisicing elit. Repellat expedita quos fugiat harum, eaque magni debitis id sunt optio animi dolorem qui beatae quasi quaerat?</div>
            </div>
          </div>
        </div>
      </div>
      <div class="columns__column">
        <div class="columns__item item">
          <div class="item__row">
            <div class="item__image">
              <img src="..//myproject/img-flex/image_3.jpg" alt="">
            </div>
            <div class="item__body">
              <div class="item__title">The description for the image</div>
              <div class="item__text">Lorem ipsum dolor sit amet consectetur adipisicing elit. Repellat expedita quos fugiat harum, eaque magni debitis id sunt optio animi dolorem qui beatae quasi quaerat?</div>
            </div>
          </div>
        </div>
        <div class="columns__column">
          <div class="columns__item item">
            <div class="item__row">
              <div class="item__image">
                <img src="..//myproject/img-flex/image_3.jpg" alt="">
              </div>
              <div class="item__body">
                <div class="item__title">The description for the image</div>
                <div class="item__text">Lorem ipsum dolor sit amet consectetur adipisicing elit. Repellat expedita quos fugiat harum, eaque magni debitis id sunt optio animi dolorem qui beatae quasi quaerat?</div>
              </div>
            </div>
          </div>
          <div class="columns__column">
            <div class="columns__item item">
              <div class="item__row">
                <div class="item__image">
                  <img src="..//myproject/img-flex/image_3.jpg" alt="">
                </div>
                <div class="item__body">
                  <div class="item__title">The description for the image</div>
                  <div class="item__text">Lorem ipsum dolor sit amet consectetur adipisicing elit. Repellat expedita quos fugiat harum, eaque magni debitis id sunt optio animi dolorem qui beatae quasi quaerat?</div>
                </div>
              </div>
            </div>
          </div>
        </div>
      </div>