/* Pop-up overlay */ .overlay { position: fixed; top: 0; left: 0; width: 100vw; height: 100vh; margin: 0; display: flex; z-index: 25; } .overlay.hidden { display: none; } /* Background */ .overlay.shade { background-color: rgba(10, 10, 10, 0.75); } /* Content */ .overlay > div.center { width: 100%; height: 100%; display: flex; justify-content: center; align-items: center; }