:root{--primary-gradient: linear-gradient(135deg, #00d4aa 0%, #00a884 50%, #008066 100%);--primary-light: #00d4aa;--primary-main: #00a884;--primary-dark: #008066;--snake-gradient-start: #00f5c4;--snake-gradient-mid: #00d4aa;--snake-gradient-end: #00a884;--snake-head: #00ffd4;--food-color: #ff6b6b;--food-glow: rgba(255, 107, 107, .6);--food-pulse: rgba(255, 107, 107, .3);--bg-primary: #0a0a0f;--bg-secondary: #12121a;--bg-tertiary: #1a1a25;--bg-gradient: linear-gradient(180deg, #0a0a0f 0%, #12121a 50%, #1a1a25 100%);--grid-color: rgba(255, 255, 255, .03);--grid-glow: rgba(0, 212, 170, .1);--text-primary: #ffffff;--text-secondary: rgba(255, 255, 255, .7);--text-muted: rgba(255, 255, 255, .5);--text-accent: #00d4aa;--glass-bg: rgba(255, 255, 255, .05);--glass-border: rgba(255, 255, 255, .1);--glass-shadow: 0 8px 32px rgba(0, 0, 0, .3);--glass-blur: blur(20px);--difficulty-easy: #4ade80;--difficulty-medium: #fbbf24;--difficulty-hard: #f87171;--shadow-sm: 0 2px 8px rgba(0, 0, 0, .2);--shadow-md: 0 4px 16px rgba(0, 0, 0, .3);--shadow-lg: 0 8px 32px rgba(0, 0, 0, .4);--shadow-glow: 0 0 30px rgba(0, 212, 170, .3);--space-xs: 4px;--space-sm: 8px;--space-md: 16px;--space-lg: 24px;--space-xl: 32px;--space-2xl: 48px;--radius-sm: 8px;--radius-md: 12px;--radius-lg: 16px;--radius-xl: 24px;--radius-full: 9999px;--transition-fast: .15s ease;--transition-base: .25s ease;--transition-slow: .4s ease}*{margin:0;padding:0;box-sizing:border-box}html{font-size:16px;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}body{font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,sans-serif;background:var(--bg-gradient);min-height:100vh;display:flex;justify-content:center;align-items:center;overflow-x:hidden;color:var(--text-primary);line-height:1.5}#app{display:flex;flex-direction:column;justify-content:center;align-items:center;padding:var(--space-lg);max-width:100vw;width:100%;gap:var(--space-lg)}.canvas-wrapper{position:relative;padding:var(--space-md);background:var(--glass-bg);border:1px solid var(--glass-border);border-radius:var(--radius-lg);box-shadow:var(--glass-shadow),var(--shadow-glow);backdrop-filter:var(--glass-blur);-webkit-backdrop-filter:var(--glass-blur)}#game-canvas{display:block;border-radius:var(--radius-md);box-shadow:inset 0 0 20px #00000080;max-width:100%;height:auto;touch-action:none;background:var(--bg-secondary)}.canvas-wrapper:before{content:"";position:absolute;top:-1px;right:-1px;bottom:-1px;left:-1px;border-radius:var(--radius-lg);padding:1px;background:linear-gradient(135deg,#00d4aa4d,#00d4aa1a,#00d4aa4d);-webkit-mask:linear-gradient(#fff 0 0) content-box,linear-gradient(#fff 0 0);mask:linear-gradient(#fff 0 0) content-box,linear-gradient(#fff 0 0);-webkit-mask-composite:xor;mask-composite:exclude;pointer-events:none}#game-ui{text-align:center;width:100%;max-width:600px;display:flex;flex-direction:column;gap:var(--space-md)}.score-container{display:flex;justify-content:center;align-items:center;gap:var(--space-xl);padding:var(--space-md) var(--space-lg);background:var(--glass-bg);border:1px solid var(--glass-border);border-radius:var(--radius-xl);backdrop-filter:var(--glass-blur);-webkit-backdrop-filter:var(--glass-blur);box-shadow:var(--glass-shadow)}.score-item{display:flex;flex-direction:column;align-items:center;gap:var(--space-xs)}.score-label{font-size:.75rem;font-weight:600;text-transform:uppercase;letter-spacing:.1em;color:var(--text-muted)}.score-value{font-size:2rem;font-weight:800;background:var(--primary-gradient);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text;line-height:1}.score-divider{width:1px;height:40px;background:linear-gradient(180deg,transparent,var(--glass-border),transparent)}.high-score .score-value{background:linear-gradient(135deg,#fbbf24,#f59e0b);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}#state-display{font-size:.875rem;color:var(--text-secondary);padding:var(--space-sm) var(--space-md);background:var(--glass-bg);border:1px solid var(--glass-border);border-radius:var(--radius-full);display:inline-flex;align-items:center;gap:var(--space-sm);margin:0 auto;backdrop-filter:var(--glass-blur);-webkit-backdrop-filter:var(--glass-blur)}#state-display strong{color:var(--text-accent);font-weight:600}#state-display.state-idle{border-color:#00d4aa4d;color:var(--primary-light)}#state-display.state-playing{border-color:#ffffff1a}#state-display.state-paused{border-color:#fbbf244d;color:#fbbf24}#state-display.state-gameover{border-color:#f871714d;color:#f87171}#difficulty-container{display:flex;flex-direction:column;gap:var(--space-md);padding:var(--space-lg);background:var(--glass-bg);border:1px solid var(--glass-border);border-radius:var(--radius-lg);backdrop-filter:var(--glass-blur);-webkit-backdrop-filter:var(--glass-blur);box-shadow:var(--glass-shadow)}.difficulty-header{display:flex;align-items:center;justify-content:center;gap:var(--space-sm);font-size:.875rem;color:var(--text-muted)}.difficulty-header .current-difficulty{font-weight:700;color:var(--text-primary);text-transform:uppercase;letter-spacing:.05em}#difficulty-buttons{display:flex;justify-content:center;gap:var(--space-md);flex-wrap:wrap}.difficulty-btn{position:relative;padding:var(--space-sm) var(--space-lg);font-size:.875rem;font-weight:600;border:2px solid transparent;border-radius:var(--radius-full);background:#ffffff0d;color:var(--text-secondary);cursor:pointer;transition:all var(--transition-base);overflow:hidden;text-transform:uppercase;letter-spacing:.05em}.difficulty-btn:before{content:"";position:absolute;top:0;right:0;bottom:0;left:0;background:linear-gradient(135deg,rgba(255,255,255,.1),transparent);opacity:0;transition:opacity var(--transition-base)}.difficulty-btn:hover{transform:translateY(-2px);box-shadow:var(--shadow-md);color:var(--text-primary)}.difficulty-btn:hover:before{opacity:1}.difficulty-btn:active{transform:translateY(0)}.difficulty-btn.active-easy{background:linear-gradient(135deg,#4ade8033,#4ade801a);border-color:var(--difficulty-easy);color:var(--difficulty-easy);box-shadow:0 0 20px #4ade804d}.difficulty-btn.active-medium{background:linear-gradient(135deg,#fbbf2433,#fbbf241a);border-color:var(--difficulty-medium);color:var(--difficulty-medium);box-shadow:0 0 20px #fbbf244d}.difficulty-btn.active-hard{background:linear-gradient(135deg,#f8717133,#f871711a);border-color:var(--difficulty-hard);color:var(--difficulty-hard);box-shadow:0 0 20px #f871714d}#leaderboard-container{padding:var(--space-lg);background:var(--glass-bg);border:1px solid var(--glass-border);border-radius:var(--radius-lg);backdrop-filter:var(--glass-blur);-webkit-backdrop-filter:var(--glass-blur);box-shadow:var(--glass-shadow)}.leaderboard-header{display:flex;align-items:center;justify-content:center;gap:var(--space-sm);margin-bottom:var(--space-md);padding-bottom:var(--space-md);border-bottom:1px solid var(--glass-border)}.leaderboard-title{font-size:1.125rem;font-weight:700;background:var(--primary-gradient);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.leaderboard-icon{font-size:1.25rem}.leaderboard-list{display:flex;flex-direction:column;gap:var(--space-sm)}.leaderboard-item{display:flex;align-items:center;justify-content:space-between;padding:var(--space-sm) var(--space-md);background:#ffffff08;border:1px solid transparent;border-radius:var(--radius-md);transition:all var(--transition-base)}.leaderboard-item:hover{background:#ffffff0d;border-color:var(--glass-border);transform:translate(4px)}.leaderboard-item.new-record{background:linear-gradient(135deg,#00d4aa26,#00d4aa0d);border-color:#00d4aa4d;animation:pulse-record 2s ease-in-out infinite}@keyframes pulse-record{0%,to{box-shadow:0 0 10px #00d4aa33}50%{box-shadow:0 0 20px #00d4aa66}}.leaderboard-rank{display:flex;align-items:center;gap:var(--space-sm);font-weight:600}.rank-medal{font-size:1.25rem}.rank-number{width:24px;height:24px;display:flex;align-items:center;justify-content:center;background:#ffffff1a;border-radius:var(--radius-sm);font-size:.75rem;color:var(--text-muted)}.leaderboard-score{font-weight:700;color:var(--text-primary)}.leaderboard-difficulty{font-size:.75rem;padding:2px 8px;border-radius:var(--radius-full);background:#ffffff1a;color:var(--text-muted)}.leaderboard-date{font-size:.75rem;color:var(--text-muted)}.leaderboard-empty{text-align:center;padding:var(--space-lg);color:var(--text-muted);font-size:.875rem}#pause-overlay{position:absolute;inset:var(--space-md);background:#0a0a0fd9;backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);border-radius:var(--radius-md);display:none;flex-direction:column;justify-content:center;align-items:center;gap:var(--space-lg);z-index:10}.pause-title{font-size:2.5rem;font-weight:800;background:linear-gradient(135deg,#fbbf24,#f59e0b);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}.pause-score{font-size:1.5rem;color:var(--text-secondary)}.pause-score-value{font-weight:700;color:var(--text-primary)}.pause-hint{font-size:.875rem;color:var(--text-muted);padding:var(--space-sm) var(--space-md);background:#ffffff0d;border-radius:var(--radius-full)}#sound-toggle-btn{position:fixed;top:var(--space-lg);right:var(--space-lg);width:48px;height:48px;border:1px solid var(--glass-border);border-radius:var(--radius-full);background:var(--glass-bg);backdrop-filter:var(--glass-blur);-webkit-backdrop-filter:var(--glass-blur);cursor:pointer;font-size:1.25rem;display:flex;align-items:center;justify-content:center;transition:all var(--transition-base);z-index:1000;box-shadow:var(--glass-shadow)}#sound-toggle-btn:hover{transform:scale(1.1);border-color:var(--primary-light);box-shadow:0 0 20px #00d4aa4d}#sound-toggle-btn:active{transform:scale(.95)}#sound-toggle-btn.sound-on{border-color:var(--primary-light);color:var(--primary-light)}#touch-controls{display:none;margin-top:var(--space-lg);user-select:none;-webkit-user-select:none}.dpad-row{display:flex;gap:var(--space-md)}.dpad-btn{width:72px;height:72px;border:2px solid var(--glass-border);border-radius:var(--radius-full);background:var(--glass-bg);backdrop-filter:var(--glass-blur);-webkit-backdrop-filter:var(--glass-blur);color:var(--text-secondary);font-size:1.5rem;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:all var(--transition-fast);touch-action:manipulation;-webkit-tap-highlight-color:transparent;box-shadow:var(--glass-shadow)}.dpad-btn:hover{border-color:#00d4aa4d;color:var(--text-primary)}.dpad-btn:active,.dpad-btn.active{background:linear-gradient(135deg,#00d4aa4d,#00d4aa1a);border-color:var(--primary-light);color:var(--primary-light);transform:scale(.95);box-shadow:0 0 20px #00d4aa4d}.game-control-btn{display:none;margin-top:var(--space-lg);padding:var(--space-md) var(--space-2xl);font-size:1rem;font-weight:600;text-transform:uppercase;letter-spacing:.05em;border:2px solid var(--primary-light);border-radius:var(--radius-full);background:transparent;color:var(--primary-light);cursor:pointer;transition:all var(--transition-base);touch-action:manipulation;-webkit-tap-highlight-color:transparent}.game-control-btn:hover{background:var(--primary-gradient);color:var(--bg-primary);transform:translateY(-2px);box-shadow:0 4px 20px #00d4aa66}.game-control-btn:active{transform:translateY(0)}.swipe-hint{display:none;margin-top:var(--space-md);font-size:.75rem;color:var(--text-muted);text-align:center}@media(max-width:768px){#app{padding:var(--space-md);gap:var(--space-md)}.canvas-wrapper{padding:var(--space-sm);border-radius:var(--radius-md)}#game-canvas{border-radius:var(--radius-sm)}.score-container{padding:var(--space-sm) var(--space-md);gap:var(--space-lg)}.score-value{font-size:1.5rem}.score-divider{height:32px}#difficulty-container{padding:var(--space-md)}.difficulty-btn{padding:var(--space-xs) var(--space-md);font-size:.75rem}#leaderboard-container{padding:var(--space-md)}.leaderboard-title{font-size:1rem}.leaderboard-item{padding:var(--space-xs) var(--space-sm)}.leaderboard-date{display:none}#touch-controls{display:flex;flex-direction:column;align-items:center;gap:var(--space-sm)}.dpad-btn{width:64px;height:64px;font-size:1.25rem}.game-control-btn,.swipe-hint{display:block}#sound-toggle-btn{width:40px;height:40px;font-size:1rem;top:var(--space-sm);right:var(--space-sm)}.pause-title{font-size:1.75rem}.pause-score{font-size:1.125rem}}@media(max-width:480px){.score-container{flex-direction:row;gap:var(--space-md)}.score-value{font-size:1.25rem}#difficulty-buttons{gap:var(--space-sm)}.difficulty-btn{padding:var(--space-xs) var(--space-sm);font-size:.7rem}.leaderboard-difficulty{display:none}}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px)}to{opacity:1;transform:translateY(0)}}@keyframes slideIn{0%{opacity:0;transform:translate(-10px)}to{opacity:1;transform:translate(0)}}@keyframes glow{0%,to{box-shadow:0 0 20px #00d4aa4d}50%{box-shadow:0 0 40px #00d4aa80}}#game-ui>*{animation:fadeIn .4s ease-out}.leaderboard-item{animation:slideIn .3s ease-out}.canvas-wrapper{animation:glow 3s ease-in-out infinite}.score-animation{position:absolute;font-size:1.5rem;font-weight:800;color:var(--primary-light);pointer-events:none;z-index:100;text-shadow:0 0 20px rgba(0,212,170,.5);animation:scoreFloat .8s ease-out forwards}@keyframes scoreFloat{0%{opacity:1;transform:translateY(0) scale(1)}to{opacity:0;transform:translateY(-50px) scale(1.3)}}