html - 水平居中图像并在图像宽度较小时也使用最大宽度叠加

Question

我的图像位于一个固定宽度的 well 中。

1. (1) 如何让我的图像始终水平居中(我尝试使用margin:0 auto 但它不起作用)。
2. (2) 我还有一个 .overlay它适用于我所有其他图像(具有max-width:300px，但对于宽度较小的示例图像，我需要叠加层也覆盖 well 的完整最大宽度(现在如本例所示，叠加层仅限于这些较小宽度图像的宽度)。怎么做这两件事可能吗？

.image-video-linkcar {
    position: relative;
    display: inline-block;
}

.image-video-linkcar img {
    max-width: auto;
    max-height: 230px;
    margin: 0;
    padding: 0;
    vertical-align: middle;
}

.categorycar {
    font-size: 10px;
    font-weight: 700;
    font-family: 'Montserrat',sans-serif;
    font-style: bold;
    text-align: center;
    color: #777;
    margin-left: 15px;
    outline: 1px solid #fff;
    padding: 2px 20px 2px 8px;
    background-color: #FFF;
    opacity: .9;
    position: absolute;
    opacity: .7;
    bottom: 0;
    right: 0;
    min-height: 0;
}

.brandcar {
    font-size: 10px;
    font-weight: 700;
    font-family: 'Montserrat',sans-serif;
    font-style: bold;
    text-align: center;
    color: #777;
    margin-left: 15px;
    outline: 1px solid #fff;
    padding: 2px 20px 2px 8px;
    background-color: #fff;
    opacity: .9;
    position: absolute;
    opacity: .7;
    top: 0;
    right: 0;
    min-height: 0;
}

.image-video-linkcar:hover .overlay {
    opacity: 1;
}


.well.carousel {
    width: 100%;
    height: auto;
    height: 420px;
    width: 400px;
    padding: 0;
    margin: 0;
    border: none;
    background-color:red
}




.product-detailscar .overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    border-radius: 0;
    background: #F7F7F7;
    color: #FFF;
    padding: 10px;
    border-top: 1px solid #A10000;
    border-bottom: 1px solid #A10000;
/*vertical-align: middle;*/
    -webkit-transition: opacity 500ms;
    -moz-transition: opacity 500ms;
    -o-transition: opacity 500ms;
    transition: opacity 500ms;
/*padding: 25px;
    text-align: center;*/
}

<div class="well carousel">
            <div class="product-detailscar">
                <div class="image-video-linkcar">
                    <img alt="#" src=
                    "http://lorempixel.com/100/200"> 
                    <div class="brandcar">
                        BRAND
                    </div>
                    <div class="categorycar">
                     CATEGORY
                    </div>
                    <div class="overlay">
                        <div class="subcategorycar">
                       SUBCAT
                    </div>
                       <div class="idcar">
                       ID
                    </div>

Answer 1

您需要将叠加层移出 .product-detailscar div。

.well {
  width: 300px;
  background: orange;
  position: relative;
  text-align: center;
}
.image-video-linkcar {
  position: relative;
  display: inline-block;
}
.image-video-linkcar img {
  max-width: auto;
  max-height: 230px;
  margin: 0;
  padding: 0;
  vertical-align: middle;
}
.categorycar {
  font-size: 10px;
  font-weight: 700;
  font-family: 'Montserrat', sans-serif;
  font-style: bold;
  text-align: center;
  color: #777;
  margin-left: 15px;
  outline: 1px solid #fff;
  padding: 2px 20px 2px 8px;
  background-color: #FFF;
  opacity: .9;
  position: absolute;
  opacity: .7;
  bottom: 0;
  right: 0;
  min-height: 0;
}
.brandcar {
  font-size: 10px;
  font-weight: 700;
  font-family: 'Montserrat', sans-serif;
  font-style: bold;
  text-align: center;
  color: #777;
  margin-left: 15px;
  outline: 1px solid #fff;
  padding: 2px 20px 2px 8px;
  background-color: #fff;
  opacity: .9;
  position: absolute;
  opacity: .7;
  top: 0;
  right: 0;
  min-height: 0;
}
.well:hover .overlay {
  opacity: 1;
}
.well .overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  border-radius: 0;
  background: rgba(0, 255, 0, .5);
  color: #FFF;
  padding: 10px;
  border-top: 1px solid #A10000;
  border-bottom: 1px solid #A10000;
}

<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" rel="stylesheet" />
<div class="well carousel">
  <div class="product-detailscar">
    <div class="image-video-linkcar">
      <img alt="#" src="http://www.fillmurray.com/100/200">
      <div class="brandcar">
        BRAND
      </div>

      <div class="categorycar">
        CATEGORY
      </div>

    </div>
  </div>
  <div class="overlay">
    <div class="subcategorycar">
      SUBBBBBBCATEGORY
    </div>

    <div class="idcar">
      IDDDDCAR
    </div>
  </div>
</div>