:root{--bg-color: #fef6f8;--card-bg: #ffffff;--primary: #ff6b81;--primary-hover: #ff4757;--accent: #70a1ff;--text-main: #2f3542;--text-muted: #747d8c;--pastel-yellow: #fff3cd;--shadow: 0 15px 35px rgba(0, 0, 0, .08);--radius: 24px}*{box-sizing:border-box;margin:0;padding:0;font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif}body{background-color:var(--bg-color);color:var(--text-main);min-height:100vh;display:flex;justify-content:center;align-items:center;overflow-x:hidden;padding:20px}#confettiCanvas{position:fixed;top:0;left:0;width:100vw;height:100vh;pointer-events:none;z-index:999}.music-btn{position:fixed;top:20px;right:20px;background:#fff;border:2px solid var(--primary);color:var(--primary);padding:8px 16px;border-radius:50px;cursor:pointer;font-weight:600;box-shadow:0 4px 12px #ff6b8133;transition:all .2s ease;z-index:1000;display:flex;align-items:center;gap:6px}.music-btn:hover{background:var(--primary);color:#fff}.container{width:100%;max-width:480px;display:flex;flex-direction:column;justify-content:center;align-items:center;position:relative}.envelope-scene{perspective:1000px;display:flex;flex-direction:column;align-items:center;gap:24px;width:100%;transition:opacity .4s ease}.envelope-3d{position:relative;width:360px;height:240px;transform-style:preserve-3d;transition:transform .8s cubic-bezier(.4,0,.2,1)}.envelope-3d.flipped{transform:rotateY(180deg)}.env-face{position:absolute;top:0;left:0;width:100%;height:100%;backface-visibility:hidden;border-radius:0;filter:drop-shadow(0 15px 30px rgba(0,0,0,.12))}.env-front{background:#f8c291;border:2px solid #ebb27d;padding:24px 20px;display:flex;flex-direction:column;justify-content:center;border-radius:0}.stamp-box{position:absolute;top:16px;right:16px;width:44px;height:52px;border:2px dashed #e2a065;background:#fff;display:flex;align-items:center;justify-content:center;font-size:1.4rem;border-radius:0}.address-box{margin-top:10px;text-align:left}.to-label{font-size:.8rem;color:#a0632d;font-weight:600}.address-box h2{font-size:1.4rem;color:#2f3542;margin:2px 0 8px}.divider-line{height:2px;background:#e2a065;width:70%;margin-bottom:8px}.from-label{font-size:.85rem;color:#855800}.env-back{transform:rotateY(180deg);background:transparent;border-radius:0;overflow:visible!important}.env-back-inner{position:absolute;top:0;left:0;width:100%;height:100%;background:#f8c291;border-radius:0;overflow:hidden;z-index:1}.env-inside{position:absolute;top:0;left:0;width:100%;height:100%;background:#c2824a;border-radius:0}.env-letter-mini{position:absolute;bottom:15px;left:50%;transform:translate(-50%);width:86%;height:110px;background:#fff;border-radius:4px;padding:12px;text-align:center;box-shadow:0 2px 8px #0000001a;z-index:2;transition:transform .6s cubic-bezier(.34,1.25,.64,1)}.preview-badge{font-size:.75rem;background:var(--pastel-yellow);color:#856404;padding:3px 10px;border-radius:12px;font-weight:700}.env-letter-mini h3{font-size:1.05rem;color:var(--primary);margin-top:8px}.env-pocket-svg{position:absolute;top:0;left:0;width:100%;height:100%;z-index:3;pointer-events:none}.env-flap-svg{position:absolute;top:0;left:0;width:100%;height:100%;z-index:4;pointer-events:none;overflow:visible!important}.flap-shape{transform-origin:50% 0px;transition:transform .6s cubic-bezier(.4,0,.2,1)}.env-seal{position:absolute;top:130px;left:50%;transform:translate(-50%);width:44px;height:44px;background:#ff6b81;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:1.2rem;box-shadow:0 4px 10px #ff6b8166;border:2px solid #ff4757;z-index:5;cursor:pointer;transition:transform .2s,opacity .3s}.env-seal:hover{transform:translate(-50%) scale(1.1)}.flip-btn{background:#fff;border:2px solid var(--accent);color:var(--accent);padding:10px 20px;border-radius:30px;font-weight:700;font-size:.9rem;cursor:pointer;box-shadow:0 4px 12px #70a1ff33;transition:all .2s ease}.flip-btn:hover{background:var(--accent);color:#fff}.envelope-3d.open .flap-shape{transform:rotateX(180deg)}.envelope-3d.open .env-seal{opacity:0;pointer-events:none}.envelope-3d.open .env-letter-mini{transform:translate(-50%) translateY(-90px)}.card-content{position:relative;background:var(--card-bg);width:100%;max-width:460px;border-radius:var(--radius);box-shadow:var(--shadow);padding:32px 24px;animation:cardZoomIn .6s cubic-bezier(.175,.885,.32,1.275) forwards;display:flex;flex-direction:column}.card-inner{display:flex;flex-direction:column;gap:16px;text-align:center}.badge{background:var(--pastel-yellow);color:#856404;font-size:.8rem;font-weight:700;padding:4px 12px;border-radius:20px;display:inline-block;margin-bottom:4px}.card-header h1{font-size:1.6rem;color:var(--primary)}.card-body{display:flex;flex-direction:column;gap:12px}.message-text{font-size:1rem;line-height:1.5;color:var(--text-main);background:#fdf2f4;padding:14px;border-radius:12px;text-align:left;white-space:pre-wrap;max-height:180px;overflow-y:auto}.card-bottom-section{display:flex;flex-direction:column;align-items:center;gap:12px;margin-top:24px;border-top:1px solid #f1f2f6;padding-top:16px}.cake-container{display:flex;flex-direction:column;align-items:center}.cake{position:relative;width:120px;height:55px;margin-top:10px}.sponge{position:absolute;bottom:0;width:100%;height:38px;background:#ff7675;border-radius:0 0 12px 12px}.frosting{position:absolute;top:6px;width:100%;height:18px;background:#fab1a0;border-radius:10px 10px 0 0}.candles-wrapper{position:absolute;top:-24px;left:50%;transform:translate(-50%);display:flex;gap:4px;z-index:2}.candle-item{position:relative;font-size:2.2rem;font-weight:900;color:#74b9ff;line-height:1;cursor:pointer;-webkit-user-select:none;user-select:none;text-shadow:2px 2px 0px rgba(0,0,0,.1);transition:transform .2s;display:flex;justify-content:center}.candle-item:hover{transform:none}.flame{position:absolute;top:-16px;left:50%;transform:translate(-50%);width:12px;height:16px;background:#ffeaa7;border-radius:50% 50% 20% 20%;box-shadow:0 0 10px #fdcb6e;animation:flicker .6s infinite alternate}.flame.extinguished{display:none}.cake-hint{font-size:.75rem;color:var(--text-muted);margin-top:6px}.card-footer{font-size:.9rem;color:var(--text-muted)}.fallback-box{background:#fff;padding:30px;border-radius:var(--radius);text-align:center;box-shadow:var(--shadow)}.fallback-box h2{color:#ff4757;margin-bottom:10px}.hidden{display:none!important}@keyframes cardZoomIn{0%{transform:scale(.6);opacity:0}to{transform:scale(1);opacity:1}}@keyframes flicker{0%{transform:translate(-50%) scale(1);opacity:.9}to{transform:translate(-50%) scale(1.15);opacity:1}}