body,html{margin:0;padding:0;width:100%;height:100%;overflow:hidden}.valentine-app{width:100%;height:100vh;display:flex;justify-content:center;align-items:center;background-image:url(/heart-bg.jpg);background-size:cover;background-position:center;font-family:Pixelify Sans,sans-serif;touch-action:manipulation}#envelope-container{text-align:center;cursor:pointer}#envelope{width:180px;animation:pulse 1.5s infinite}@keyframes pulse{0%{transform:scale(1)}50%{transform:scale(1.05)}to{transform:scale(1)}}#letter-container{display:flex;justify-content:center;align-items:center;width:100%;height:100%}.letter-window{width:60vw;max-width:800px;aspect-ratio:3/2;display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center;background-image:url(/window.png);background-size:contain;background-repeat:no-repeat;background-position:center;padding:10% 5% 5%;transform:scale(.9);opacity:0;transition:transform .5s ease-out,opacity .5s ease-out}.letter-window.open{transform:scale(1);opacity:1}h1{font-size:2vw;min-size:18px;margin:0;color:#333}.cat{width:40%;max-width:200px;margin:10px 0}.buttons{display:flex;justify-content:center;gap:2vw;position:relative;width:100%}.btn{width:8vw;max-width:110px;min-width:60px;cursor:pointer;-webkit-tap-highlight-color:transparent}.no-btn{transition:transform .2s ease}.final-text{font-size:1.5vw;min-size:14px;background-color:#fff6;border-radius:8px;padding:5px}@media(max-width:768px){.letter-window{width:90vw}h1{font-size:5vw}.final-text{font-size:4vw}.btn{width:25vw}}