*{margin:0;padding:0;box-sizing:border-box}body{background:#0a0a1a;color:#e0e0e0;font-family:Segoe UI,PingFang SC,Microsoft YaHei,sans-serif;min-height:100vh;display:flex;justify-content:center;align-items:center;overscroll-behavior:none;-webkit-overflow-scrolling:auto}#root{width:100%;display:flex;justify-content:center}.app{display:flex;flex-direction:column;align-items:center;padding:20px 12px;-webkit-user-select:none;user-select:none;max-width:600px;width:100%}.title{font-size:1.8rem;margin-bottom:10px;background:linear-gradient(135deg,#00e676,#69f0ae);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.header{display:flex;align-items:center;gap:10px;margin-bottom:14px;flex-wrap:wrap;justify-content:center}.score{font-size:1.15rem;font-weight:600;color:#00e676}.diff-badge{font-size:.85rem;font-weight:700;padding:2px 10px;border:1px solid currentColor;border-radius:4px}.icon-btn{width:36px;height:36px;font-size:1.1rem;background:#1a1a3e;border:1px solid #333366;border-radius:6px;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:all .2s;line-height:1}.icon-btn:hover{border-color:#00e676;box-shadow:0 0 8px #00e6764d}.restart-btn{padding:6px 16px;font-size:.9rem;background:#1a1a3e;color:#00e676;border:1px solid #00e676;border-radius:6px;cursor:pointer;transition:all .2s}.restart-btn:hover{background:#00e676;color:#0a0a1a}.board-wrapper{position:relative;touch-action:manipulation}.board{display:grid;gap:1px;width:min(85vw,90vmin,480px);height:min(85vw,90vmin,480px);background:#113;border:2px solid #333366;border-radius:4px;padding:1px}.cell{background:#1a1a3e;border-radius:2px}.cell--snake{background:#00e676;border-radius:3px}.cell--head{background:#69f0ae;border-radius:4px;box-shadow:0 0 6px #69f0ae}.cell--food{background:#ff5252;border-radius:50%;box-shadow:0 0 8px #ff5252;animation:pulse .6s ease-in-out infinite alternate}.cell--bonus{background:#ffd740;border-radius:50%;box-shadow:0 0 10px #ffd740;animation:pulse-gold .5s ease-in-out infinite alternate}@keyframes pulse{0%{box-shadow:0 0 4px #ff5252}to{box-shadow:0 0 12px #ff5252}}@keyframes pulse-gold{0%{box-shadow:0 0 6px #ffd740}to{box-shadow:0 0 16px #ffd740}}.particle{position:absolute;width:6px;height:6px;border-radius:50%;pointer-events:none;z-index:10;animation:particle-fly .35s ease-out forwards}@keyframes particle-fly{0%{opacity:1;transform:translate(0) scale(1)}to{opacity:0;transform:translate(var(--dx),var(--dy)) scale(.2)}}.overlay{position:absolute;top:0;right:0;bottom:0;left:0;display:flex;justify-content:center;align-items:center;background:#000000bf;border-radius:4px;z-index:5}.overlay__box{text-align:center;padding:28px 36px;background:#1a1a3e;border:2px solid #333366;border-radius:12px;max-width:320px}.overlay__box--wide{max-width:360px}.overlay__title{font-size:1.7rem;color:#ff5252;margin-bottom:10px}.overlay__pause-title{font-size:1.5rem;color:#ffab40;margin-bottom:16px}.overlay__start-title{font-size:1.3rem;color:#69f0ae;margin-bottom:14px}.overlay__score{font-size:1.2rem;color:#00e676;margin-bottom:16px}.overlay__hint{font-size:.95rem;color:#aaf;margin-top:14px}.overlay__highscore-hint{color:#ffd740;font-size:.95rem;margin-bottom:10px}.overlay__noboard-hint{color:#666;font-size:.85rem;margin-bottom:8px}.overlay__submit{margin-bottom:12px}.overlay__input{display:block;width:100%;padding:8px 12px;margin:0 auto 12px;font-size:1rem;background:#0a0a1a;color:#e0e0e0;border:2px solid #333366;border-radius:6px;outline:none;text-align:center;transition:border-color .2s}.overlay__input:focus{border-color:#00e676}.overlay__input::placeholder{color:#555}.overlay__btn{padding:10px 32px;font-size:1rem;background:#00e676;color:#0a0a1a;border:none;border-radius:8px;cursor:pointer;font-weight:600;transition:transform .15s,box-shadow .15s;margin:6px 0}.overlay__btn:hover{transform:scale(1.05);box-shadow:0 0 16px #00e67680}.diff-selector{display:flex;gap:10px;justify-content:center;margin-bottom:4px}.diff-card{flex:1;padding:12px 8px;background:#1a1a3e;border:2px solid #333366;border-radius:10px;cursor:pointer;display:flex;flex-direction:column;align-items:center;gap:6px;transition:all .2s}.diff-card:hover{border-color:#666;transform:translateY(-2px)}.diff-card--selected{background:#1f1f4a;box-shadow:0 0 12px #00e67626}.diff-card__label{font-size:1rem;font-weight:700}.diff-card__info{font-size:.8rem;color:#999}.leaderboard{width:100%;max-width:480px;margin-bottom:14px;padding:14px 16px;background:#113;border:1px solid #333366;border-radius:8px}.leaderboard--compact{margin:0 0 10px;padding:10px;max-width:100%}.leaderboard__title{font-size:1rem;color:#ffd740;margin-bottom:10px;text-align:center}.leaderboard__table,.leaderboard__list{font-size:.85rem}.leaderboard__header,.leaderboard__row{display:grid;grid-template-columns:30px 1fr 50px 50px 70px;gap:8px;padding:5px 6px;align-items:center}.leaderboard__header{color:#77a;font-weight:600;border-bottom:1px solid #222;padding-bottom:8px;margin-bottom:4px}.leaderboard__row:nth-child(odd){background:#ffffff05}.leaderboard--compact .leaderboard__row{grid-template-columns:30px 1fr 50px}.leaderboard__rank{color:#888;font-weight:700}.leaderboard__score{color:#00e676;font-weight:600}.leaderboard__diff{font-weight:600;font-size:.8rem}.leaderboard__date{color:#666;font-size:.78rem}.leaderboard__empty{text-align:center;color:#666;font-size:.9rem;padding:16px}.stats-panel{width:100%;max-width:480px;margin-bottom:14px;padding:14px 16px;background:#113;border:1px solid #333366;border-radius:8px}.stats-panel__header{display:flex;justify-content:space-between;align-items:center;margin-bottom:12px}.stats-panel__header h3{font-size:1rem;color:#69f0ae}.stats-panel__close{background:none;border:none;color:#666;font-size:1.2rem;cursor:pointer;padding:4px}.stats-panel__close:hover{color:#ff5252}.stats-panel__grid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px}.stats-item{text-align:center;padding:10px 4px;background:#1a1a3e;border-radius:8px}.stats-item__value{display:block;font-size:1.3rem;font-weight:700;color:#00e676}.stats-item__label{font-size:.75rem;color:#888;margin-top:2px}.dpad{display:grid;grid-template-areas:".    up    ." "left .    right" ".    down  .";grid-template-columns:repeat(3,56px);grid-template-rows:repeat(3,56px);gap:4px;margin-top:16px;justify-content:center}.dpad__btn{width:56px;height:56px;font-size:1.3rem;background:#00e6761a;color:#00e676;border:1px solid rgba(0,230,118,.3);border-radius:12px;cursor:pointer;display:flex;align-items:center;justify-content:center;-webkit-tap-highlight-color:transparent;touch-action:manipulation;-webkit-user-select:none;user-select:none}.dpad__btn:active{background:#00e6764d;border-color:#00e676}.dpad__btn--up{grid-area:up}.dpad__btn--down{grid-area:down}.dpad__btn--left{grid-area:left}.dpad__btn--right{grid-area:right}@media (max-width: 480px){.app{padding:12px 8px}.title{font-size:1.4rem;margin-bottom:8px}.header{gap:6px;margin-bottom:10px}.score{font-size:1rem}.board{width:92vw;height:92vw}.overlay__box{padding:20px 24px;max-width:280px}.overlay__title{font-size:1.4rem}.diff-card{padding:10px 6px}.diff-card__label{font-size:.9rem}.dpad{grid-template-columns:repeat(3,48px);grid-template-rows:repeat(3,48px);margin-top:12px}.dpad__btn{width:48px;height:48px;font-size:1.1rem}.leaderboard__header,.leaderboard__row{grid-template-columns:25px 1fr 40px 40px 55px;gap:4px;font-size:.78rem}.stats-panel__grid{grid-template-columns:repeat(2,1fr)}}@media (max-width: 360px){.board{gap:.5px}.dpad{grid-template-columns:repeat(3,40px);grid-template-rows:repeat(3,40px);gap:3px}.dpad__btn{width:40px;height:40px;font-size:1rem;border-radius:10px}}@media (max-height: 500px) and (orientation: landscape){.app{padding:6px 8px;flex-direction:row;gap:16px;align-items:flex-start}.title{display:none}.header{flex-direction:column;gap:6px}.board{width:auto;height:85vh}.dpad{margin-top:0}}