Example code for implementing a hollow mask layer with CSS

Contents of this article: Page hollow mask layer, page hollow mask guide layer, image hollow mask

Regular mask layer

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, minimum-scale=1, user-scalable=no">
    <title>Title</title>
    <style>
        .mask{
   position: absolute;
   width: 100%;
   height: 100%;
   top: 0;
   left: 0;
   background: rgba(0,0,0,0.4);
   display: flex;
   justify-content: center;
   align-items: center;
   z-index: 3;
  }
  .mask{
   position:fixed;
      top : 0;
      left : 0;
      bottom : 0;
      right : 0;
      background:rgba(0,0,0,.5); 
      /*background:hsla(0,100%,80%,0.5)*/
      /*background:#000; opacity:0.5; */
  }
  //Blur effect frosted glass effect.blur{
   -webkit-filter: blur(5px); /* Chrome, Opera */
   -moz-filter:blur(5px);
   -ms-filter:blur(5px);    
   filter: blur(5px);
  }
</style>
</head>
<style>

</style>
<body>

<div class='mask'></div>

</body>
</html>

The effect of the hollow mask layer is shown in the figure

Use box-shadow to achieve hollow mask guide layer effect

advantage:

Rounded corners are easily achieved;
Box-shadow will not affect the position of the element, and the positioning only needs to be written according to the position of the content.

Disadvantages: The shadow visible area cannot trigger the click event, so when you click any area of the mask, it cannot be hidden.

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, minimum-scale=1, user-scalable=no">
    <title>Title</title>
    <style>
        .guide{
      position: absolute;
      z-index: 2;

   top: 0px;
      left: 50%;
      transform: translateX(-50%);
      
      width: 50px;
      height: 50px;
      border-radius: 50px;
      border: 3px solid #2353FA;
      
      box-shadow: 0px 0px 0px 1000px rgba(0,0,0,.75);
      box-sizing: border-box;
    }
    </style>
</head>
<style>
</style>
<body>
<div class='guide'></div>
</body>
</html>

Use border to achieve hollow mask guide layer effect

Disadvantages: Large amount of code

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, minimum-scale=1, user-scalable=no">
    <title>Title</title>
    <style>
     .guide{
      position: absolute;
      z-index: 2;
      .opacityEle{
        border: 700px solid rgba(0,0,0,0.75);
        width: 50px;
        height: 50px;
        position: relative;
        top: -700px;
        left: -538px;
        border-radius: 50%;
        .ele{
          width: 50px;
          height: 50px;
          border: 3px solid #0B6EFF;
          border-radius: 25px;
          box-sizing: border-box;
        }
      }
    }
    </style>
</head>
<style>

</style>
<body>

<div class='guide'>
 <div class='opacityEle'>
  <div class='ele'></div>
 </div>
</div>
</body>
</html>

This concludes this article about the sample code for implementing a hollow mask layer with CSS. For more information on CSS hollow mask layers, please search previous articles on 123WORDPRESS.COM or continue browsing the following related articles. I hope you will support 123WORDPRESS.COM in the future!

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