body, html {
   height: 100%;
   margin: 0;
   font-family: Arial, sans-serif;
   background-color: #fff;
}
.container {
   display: flex;
   flex-direction: column;
   justify-content: center;
   align-items: center;
   text-align: center;
   min-height: 100%;
}
.container > * {
   margin: 15px 0;
}
nav a {
   font-size: 1.1em;
   margin: 0 10px;
   color: #0000EE; /* Default link color */
   text-decoration: none;
}
nav a:hover {
   text-decoration: underline;
}
#gallery-placeholder {
   width: 500px;
   height: 500px;
   border: 1px solid #ccc;
   display: flex;
   justify-content: center;
   align-items: center;
   background-color: #f0f0f0;
}