<p>我正在开发一个需要多个图形并排显示并且能够根据设备屏幕大小自适应的pfsense captive portal。使用图像输入类型可以很好地实现这一点。然而，pfsense设备无法正确识别此提交。它需要一种带有值为“Continue”的提交类型才能工作。</p> <p>我尝试使用背景图像来替代，但是背景图像无法缩放。随着屏幕变小，它会显示为全尺寸并被裁剪。</p> <p>我该如何使背景图像自适应大小？</p> <pre class="brush:php;toolbar:false;">&lt;style&gt; #content{font-family:'Source Sans Pro',sans-serif;background-color: gray; -webkit-background-size:cover; -moz-background-size:cover; -o-background-size:cover; background-size:cover; display:table-cell; vertical-align:middle;} #content{text-align:center} body,html{margin:0; padding:0; width:100%; height:100%; display:table} .row {display: flex;} .column {flex: 50%; padding: 50px;} input { background-size: contain; resize: both; border: 0; width: 100%; max-width: 100%; padding: 0 0 50%; object-fit: scale-down; text-indent: 100%; white-space: nowrap; overflow: hidden; } @media screen and (max-width: 500px) { .column { width: 100%; } } &lt;/style&gt; .... &lt;body&gt; &lt;div id="content"&gt; &lt;div class="row"&gt; &lt;div class="column"&gt; &lt;form name="login_form" method="post" action="$PORTAL_ACTION$"&gt; &lt;input name="redirurl" type="hidden" value="https://url"&gt; &lt;input name="accept" type="submit" style="background: url(image1.png) no-repeat;" value="Continue"&gt; &lt;input name="zone" type="hidden" value="$PORTAL_ZONE$"&gt; &lt;/form&gt; &lt;/div&gt; &lt;div class="column"&gt; &lt;form name="login_form" method="post" action="$PORTAL_ACTION$"&gt; &lt;input name="redirurl" type="hidden" value="https://url"&gt; &lt;input name="accept" type="submit" style="background: url(image2.png) no-repeat;" value="Continue"&gt; &lt;input name="zone" type="hidden" value="$PORTAL_ZONE$"&gt; &lt;/form&gt; &lt;/div&gt; &lt;/div&gt; &lt;/body&gt;</pre> <p><br /></p>

<input name="accept" type="submit" style="background: url(https://picsum.photos/1500/1500?random=1) no-repeat; background-size: cover;" value="继续">

#content{font-family:'Source Sans Pro',sans-serif;background-color: gray; -webkit-background-size:cover; -moz-background-size:cover; -o-background-size:cover; background-size:cover; display:table-cell; vertical-align:middle;}
#content{text-align:center} body,html{margin:0; padding:0; width:100%; height:100%; display:table}    
.row {display: flex;}
.column {flex: 50%; padding: 50px;}
input {
    background-size: contain;
    resize: both;
    border: 0;
    width: 100%;
    max-width: 100%;
    padding: 0 0 50%;
    object-fit: scale-down;
    text-indent: 100%;
    white-space: nowrap;
    overflow: hidden;
}
@media screen and (max-width: 500px) {
    .column {
        width: 100%;
    }
}

<div id="content">
<div class="row">
  <div class="column">
    <form name="login_form" method="post" action="$PORTAL_ACTION$">
        <input name="redirurl" type="hidden" value="https://url">
        <input name="accept" type="submit" style="background: url(https://picsum.photos/1500/1500?random=1) no-repeat; background-size: cover;" value="继续">
        <input name="zone" type="hidden" value="$PORTAL_ZONE$">
    </form>
  </div>
  <div class="column">
    <form name="login_form" method="post" action="$PORTAL_ACTION$">
        <input name="redirurl" type="hidden" value="https://url">
        <input name="accept" type="submit" style="background: url(https://picsum.photos/1500/1500?random=2) no-repeat; background-size: cover;" value="继续">
        <input name="zone" type="hidden" value="$PORTAL_ZONE$">
    </form>
  </div>
</div>