图片大小不适合div

我必须适合我的div大小是height=250px和width=1000px，并希望自动适合这个大小的图像。但是当我上传图片时，它不适合div

我的代码在这里:

css

#main {
  width:1000px;
  margin:0 auto;
  background: #fff;
  position:relative;
  z-index:1;
}
.promo-image {
  margin:0 0 8px;
}
.promo-image img {
  vertical-align:top;
}

:

<main id="main" role="main">
  <div class="promo-img">
    <?php
      $sql4 = "SELECT * FROM adverts_top ORDER BY id DESC LIMIT 1";
      $query4 = $conn->query($sql4);
      $row4 = $query4->fetch(PDO::FETCH_ASSOC);
      $link4 = $row4['link_url'];
      $images4 = $row4['imagepath'];
      $immg4 = basename($images4);
      $imagee4 = "adverts"."/".$immg4;
      $rowc = $query4->rowCount(PDO::FETCH_ASSOC);
      if ($rowc>=1) {
        echo "
            <a href='$link4'; target='_blank'><img src='$imagee4';></a>
             ";
      }
      else {
            echo "";
      }
   ?>
  </div>
</main>

<a href='$link4'; target='_blank'><img src='$imagee4'; style="width:100%"></a>

<a href='$link4'; target='_blank'><img src='$imagee4'; class="fullWidth"></a>
.fullWidth{
  width:100%;
}

.promo-image {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 8px;
  left: 0;
}