*{margin:0;padding:0;box-sizing:border-box}body{font-family:SF Pro Display,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background:linear-gradient(135deg,#667eea,#764ba2);color:#2c3e50;overflow-x:hidden}#root{width:100%;min-height:100vh;display:flex;align-items:center;justify-content:center;padding:20px}.game{max-width:550px;margin:0 auto;padding:30px;font-family:SF Pro Display,Helvetica Neue,Arial,sans-serif;text-align:center;background:#fffffff2;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);border-radius:20px;box-shadow:0 20px 40px #0000001a,0 10px 20px #0000000d;border:1px solid rgba(255,255,255,.2)}.game-header h1{font-size:60px;font-weight:800;background:linear-gradient(135deg,#667eea,#764ba2);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;margin:0 0 10px;letter-spacing:-2px}.game-description{color:#5a6c7d;font-size:18px;margin-bottom:25px;font-weight:500}.game-status{position:relative;margin-bottom:25px}.scores{display:flex;gap:15px;justify-content:center;margin-bottom:25px}.score-container{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;border-radius:15px;padding:15px 20px;min-width:100px;text-align:center;box-shadow:0 8px 16px #667eea4d;border:1px solid rgba(255,255,255,.2);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px)}.score-label{font-size:12px;font-weight:600;text-transform:uppercase;margin-bottom:6px;opacity:.9;letter-spacing:1px}.score-value{font-size:28px;font-weight:700;text-shadow:0 2px 4px rgba(0,0,0,.1)}.game-message{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);background:#fffffffa;-webkit-backdrop-filter:blur(20px);backdrop-filter:blur(20px);border-radius:20px;padding:40px;box-shadow:0 20px 40px #0003,0 10px 20px #0000001a;z-index:100;text-align:center;min-width:320px;border:2px solid rgba(255,255,255,.3);animation:modalAppear .3s cubic-bezier(.25,.46,.45,.94)}@keyframes modalAppear{0%{opacity:0;transform:translate(-50%,-50%) scale(.8) rotate(5deg)}to{opacity:1;transform:translate(-50%,-50%) scale(1) rotate(0)}}.game-message h2{font-size:36px;margin:0 0 15px;font-weight:700;letter-spacing:-1px}.game-message p{font-size:18px;color:#5a6c7d;margin-bottom:25px;font-weight:500}.game-won h2{background:linear-gradient(135deg,#43e97b,#38f9d7);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.game-over h2{background:linear-gradient(135deg,#fa709a,#fee140);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.game-message-buttons{display:flex;gap:15px;justify-content:center}.game-board{position:relative;margin:0 auto 25px;background:linear-gradient(135deg,#f5f7fa,#c3cfe2);border-radius:15px;padding:15px;width:380px;height:380px;box-shadow:inset 0 2px 10px #0000001a,0 8px 16px #0000001a;border:2px solid rgba(255,255,255,.3)}.grid-container{position:relative;width:100%;height:100%}.grid-background{position:absolute;display:grid;grid-template-columns:repeat(4,1fr);grid-template-rows:repeat(4,1fr);gap:12px;width:100%;height:100%}.grid-cell{background:#fff6;border-radius:8px;border:1px solid rgba(255,255,255,.2)}.grid-tiles{position:absolute;width:100%;height:100%}.tile{position:absolute;width:calc(25% - 9px);height:calc(25% - 9px);background:var(--tile-bg);color:var(--tile-color);border-radius:10px;font-size:var(--tile-font-size);font-weight:700;display:flex;align-items:center;justify-content:center;transition:all .25s cubic-bezier(.25,.46,.45,.94);top:calc(var(--row) * 25% + var(--row) * 12px + 15px);left:calc(var(--col) * 25% + var(--col) * 12px + 15px);box-shadow:0 4px 12px #00000026,0 2px 6px #0000001a;border:1px solid rgba(255,255,255,.2);text-shadow:0 1px 2px rgba(0,0,0,.1)}.tile-new{animation:appear .3s cubic-bezier(.175,.885,.32,1.275)}.tile-merged{animation:merge .25s cubic-bezier(.25,.46,.45,.94)}@keyframes appear{0%{opacity:0;transform:scale(0) rotate(180deg)}to{opacity:1;transform:scale(1) rotate(0)}}@keyframes merge{0%{transform:scale(1)}50%{transform:scale(1.15) rotate(5deg)}to{transform:scale(1) rotate(0)}}.controls{margin-top:25px}.instructions{color:#5a6c7d;font-size:16px;margin-bottom:20px;font-weight:500}.control-buttons{margin-bottom:25px}.restart-button,.continue-button{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;border:none;border-radius:25px;padding:12px 25px;font-size:16px;font-weight:600;cursor:pointer;transition:all .3s cubic-bezier(.25,.46,.45,.94);margin:0 8px;box-shadow:0 6px 12px #667eea4d;border:1px solid rgba(255,255,255,.2);text-shadow:0 1px 2px rgba(0,0,0,.1)}.restart-button:hover,.continue-button:hover{transform:translateY(-2px);box-shadow:0 8px 20px #667eea66;background:linear-gradient(135deg,#7b8cec,#8a5fb6)}.mobile-controls{margin-top:25px}.direction-buttons{display:flex;flex-direction:column;align-items:center;gap:12px}.middle-row{display:flex;gap:25px}.direction-button{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;border:none;border-radius:12px;width:55px;height:55px;font-size:24px;font-weight:600;cursor:pointer;transition:all .3s cubic-bezier(.25,.46,.45,.94);display:flex;align-items:center;justify-content:center;box-shadow:0 6px 12px #667eea4d;border:1px solid rgba(255,255,255,.2)}.direction-button:hover:not(:disabled){transform:translateY(-2px) scale(1.05);background:linear-gradient(135deg,#7b8cec,#8a5fb6);box-shadow:0 8px 20px #667eea66}.direction-button:disabled{background:linear-gradient(135deg,#cdc1b4,#b8aca0);cursor:not-allowed;transform:none;box-shadow:0 2px 4px #0000001a}.game-explanation{margin-top:30px;color:#5a6c7d;font-size:15px;line-height:1.6;text-align:left;background:#fff9;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);padding:20px;border-radius:15px;border:1px solid rgba(255,255,255,.3);box-shadow:0 4px 12px #0000000d;font-weight:500}@media (max-width: 480px){.game{padding:20px;max-width:95vw;border-radius:15px}.game-header h1{font-size:48px;letter-spacing:-1px}.game-description{font-size:16px}.game-board{width:320px;height:320px;padding:12px}.grid-background{gap:10px}.tile{width:calc(25% - 7.5px);height:calc(25% - 7.5px);top:calc(var(--row) * 25% + var(--row) * 10px + 12px);left:calc(var(--col) * 25% + var(--col) * 10px + 12px);font-size:calc(var(--tile-font-size) * .85);border-radius:8px}.mobile-controls{display:block}.score-container{padding:12px 16px;min-width:85px}.score-value{font-size:24px}.game-message{min-width:280px;padding:30px 25px}.game-message h2{font-size:30px}}@media (min-width: 481px){.mobile-controls{display:none}}@media (max-width: 320px){.game{padding:15px}.game-board{width:280px;height:280px}.game-header h1{font-size:40px}}