#Wien

w3schools: How TO – Image Grid https://www.w3schools.com/howto/howto_js_image_grid.asp

HTML – Layout (2 columns)

  <div class="row">  
  <div class="column">
<body><a target="_blank" href="Photo1.jpeg"><img src="Photo1.jpeg"></a></body>
<body><a target="_blank" href="Photo2.jpeg"><img src="Photo2.jpeg"></a></body>
<body><a target="_blank" href="Photo3.jpeg"><img src="Photo3.jpeg"></a></body>
<body><a target="_blank" href="Photo4.jpeg"><img src="Photo4.jpeg"></a></body>
  </div>
  <div class="column">
<body><a target="_blank" href="Photo1.jpeg"><img src="Photo1.jpeg"></a></body>
<body><a target="_blank" href="Photo2.jpeg"><img src="Photo2.jpeg"></a></body>
<body><a target="_blank" href="Photo3.jpeg"><img src="Photo3.jpeg"></a></body>
<body><a target="_blank" href="Photo4.jpeg"><img src="Photo4.jpeg"></a></body>
  </div>
</div>

CSS

img:hover {
  filter: opacity(70%);
} 

    #blog-title a {
    color: black;
    text-decoration: none;
    }
    
a:link {
  color: grey;
  background-color: transparent;
  text-decoration: none;
}

a:visited {
  color: grey;
  background-color: transparent;
  text-decoration: none;
}

/* Create two equal columns that sits next to each other */
.column {
  flex: 50%;
  padding: 0 4px;
}

.column img {
  margin-top: 8px;
  vertical-align: middle;
}