Html - 模态图像顶部的半透明div

Question

我想在facebook上做类似的事情：

它是图像模式，顶部有半透明div。我想成功，但不能。我做了div，但它不会出现，无论我如何建立CSS ... 直到现在，我有这个代码：

<div id="imgmodal">
<div class="semi-transparent">
<a id="download-link" download="Slika Testa"><span class="glyphicon glyphicon-download"></span></a>
  <span id="close">&times;</span>
</div>
  <img class="content" id="img">

</div>

和css：

/* exam_img */
#imgmodal {
    display: none; 
    position: fixed; 
    z-index: 1; 
    left: 0;
    top: 0;
    width: 100%;
    height: 100%; /* Full height */
    background-color: rgb(0,0,0); /* Fallback color */
    overflow: auto;
    background-color: rgb(0,0,0); /* Black w/ opacity */
    transition: 0.3s;
}

/* Modal Content (image) */
.content {
    margin: auto;
    display: block;
    width: auto;
    max-width: 100%;
    height: auto;
    max-height: 95%;
    position: relative;
    top: calc(50% - 25px);
    top: -moz-calc(50% - 25px);
    top: -webkit-calc(50% - 25px);
    transform: translateY(-50%);
    -webkit-transform: translateY(-50%);
    -moz-transform: translateY(-50%);   
}


/* Add Animation */
.content{    
    -webkit-animation-name: zoom;
    -webkit-animation-duration: 1s;
    animation-name: zoom;
    animation-duration: 1s;
}

@-webkit-keyframes zoom {
    0%   { opacity: 0; }
    100% { opacity: 1; }
}

@keyframes zoom {
    0%   { opacity: 0; }
    100% { opacity: 1; }
}

/* The Close Button */
#close {
    position: absolute;
    top: 15px;
    right: 35px;
    color: #f1f1f1;
    font-size: 40px;
    font-weight: 100;
    transition: 0.3s;
}

#close:hover,
#close:focus {
    color: #989898;
    text-decoration: none;
    cursor: pointer;
}
#download-link{
    position: absolute;
    font-size: 25px;
    color: #f1f1f1;
    font-weight: normal;
    text-decoration: none;
    transition: 0.2s;
    top: 27px;
    left: 35px;
}
#download-link:hover {
    color: #989898;
}

/* 100% Image Width on Smaller Screens */
@media only screen and (max-width: 768px){
    .content {

    }
    #close {
    top: 2px;
    font-size: 40px;
    }
    #imgmodal {
        padding-top: 50px;
    }
    #download-link {
        top: 15px;

    }
}
.semi-transparent {
   ?
}

Answer 1

要将.semi-transparent放在这样的图像上，您可以使用position: absolute将菜单放在图像的顶部，然后opacity使整个条形图显示为半透明。< / p>

＆＃13;

＆＃13;

/* exam_img */
#imgmodal {
    position: fixed; 
    z-index: 1; 
    left: 0;
    top: 0;
    width: 100%;
    height: 100%; /* Full height */
    background-color: rgb(0,0,0); /* Fallback color */
    overflow: auto;
    background-color: rgb(0,0,0); /* Black w/ opacity */
    transition: 0.3s;
}

/* Modal Content (image) */
.content {
    margin: auto;
    display: block;
    width: auto;
    max-width: 100%;
    height: auto;
    max-height: 95%;
    position: relative;
    top: calc(50% - 25px);
    top: -moz-calc(50% - 25px);
    top: -webkit-calc(50% - 25px);
    transform: translateY(-50%);
    -webkit-transform: translateY(-50%);
    -moz-transform: translateY(-50%);   
}


/* Add Animation */
.content{    
    -webkit-animation-name: zoom;
    -webkit-animation-duration: 1s;
    animation-name: zoom;
    animation-duration: 1s;
}

@-webkit-keyframes zoom {
    0%   { opacity: 0; }
    100% { opacity: 1; }
}

@keyframes zoom {
    0%   { opacity: 0; }
    100% { opacity: 1; }
}

/* The Close Button */
#close {
    position: absolute;
    top: 15px;
    right: 35px;
    color: #f1f1f1;
    font-size: 40px;
    font-weight: 100;
    transition: 0.3s;
}

#close:hover,
#close:focus {
    color: #989898;
    text-decoration: none;
    cursor: pointer;
}
#download-link{
    position: absolute;
    font-size: 25px;
    color: #f1f1f1;
    font-weight: normal;
    text-decoration: none;
    transition: 0.2s;
    top: 27px;
    left: 35px;
}
#download-link:hover {
    color: #989898;
}

/* 100% Image Width on Smaller Screens */
@media only screen and (max-width: 768px){
    .content {

    }
    #close {
    top: 2px;
    font-size: 40px;
    }
    #imgmodal {
        padding-top: 50px;
    }
    #download-link {
        top: 15px;

    }
}
.semi-transparent {
  text-align: center;
  color: white;
  position: absolute;
  top: 0; left: 0; right: 0;
  opacity: 0.8;
  padding: 2em 0;
}

＆＃13;

<div id="imgmodal">
  <a id="download-link" download="Slika Testa"><span class="glyphicon glyphicon-download"></span></a>
  <span id="close">&times;</span>
  <img class="content" id="img" src="http://cdn.thedailybeast.com/content/dailybeast/articles/2015/03/31/neil-degrasse-tyson-defends-scientology-and-the-bush-administration-s-science-record/jcr:content/image.img.2000.jpg/1432067001553.cached.jpg">
  <div class="semi-transparent">foobar
  </div>
</div>

＆＃13;

＆＃13;

＆＃13;