.tree-node{transition:transform .2s ease}.tree-node--clickable:hover{transform:scale(1.1)}.tree-node--clickable:active{transform:scale(.95)}.branch-screen{min-height:100vh;min-height:100dvh;padding:0 16px;display:flex;flex-direction:column;position:relative;overflow:hidden;transition:background 1.2s ease}.branch-screen--level-1{background:radial-gradient(ellipse at 50% 40%,#0d2a12,#060e07 70%)}.branch-screen--level-2{background:linear-gradient(180deg,#0a0e1a,#0d1520 30%,#0f1a15 70%,#0a120d)}.branch-screen--level-3{background:linear-gradient(180deg,#1a2435,#2a3548 20%,#3d4a3a,#5a6b45 80%,#6b7c52)}.branch-screen--level-4{background:linear-gradient(180deg,#87ceeb,#98d4e8 25%,#7ab87a 60%,#4a7c4a)}.happy-sun{position:absolute;top:12px;pointer-events:none;z-index:0}.happy-sun--right{right:50px;left:auto}.happy-sun--left{left:12px;right:auto}.happy-sun-svg{width:100%;height:100%;filter:drop-shadow(0 0 12px rgba(255,193,7,.5))}.happy-sun-svg .sun-rays line{animation:ray-pulse 2s ease-in-out infinite}.happy-sun-svg .sun-rays line:nth-child(odd){animation-delay:.3s}@keyframes ray-pulse{0%,to{opacity:.9}50%{opacity:1}}.clouds{position:absolute;top:0;right:0;bottom:0;left:0;pointer-events:none;z-index:0}.cloud{position:absolute;display:flex;gap:8px;align-items:center;animation:cloud-drift 25s linear infinite}.cloud-puff{display:block;width:36px;height:36px;border-radius:50%;background:#fffffff2;box-shadow:0 0 24px #fff9}.cloud-puff:nth-child(1){width:32px;height:32px;margin-left:0}.cloud-puff:nth-child(2){width:48px;height:42px}.cloud-puff:nth-child(3){width:34px;height:34px}@keyframes cloud-drift{0%{transform:translate(-20%) scale(var(--cloud-scale, 1))}to{transform:translate(120vw) scale(var(--cloud-scale, 1))}}.stars{position:absolute;top:0;right:0;bottom:0;left:0;pointer-events:none;z-index:0}.star{position:absolute;border-radius:50%;background:#fff;box-shadow:0 0 4px #fffc;animation:star-twinkle 3s ease-in-out infinite}.stars--dawn .star{animation:star-fade 4s ease-in-out infinite}@keyframes star-twinkle{0%,to{opacity:.7;transform:scale(1)}50%{opacity:1;transform:scale(1.2)}}@keyframes star-fade{0%,to{opacity:.3}50%{opacity:.6}}.branch-dawn-glow{position:absolute;bottom:0;left:0;right:0;height:45%;background:linear-gradient(to top,rgba(255,180,100,.15) 0%,rgba(255,140,80,.08) 30%,transparent 70%);pointer-events:none;z-index:0}.snowflakes{position:absolute;top:0;right:0;bottom:0;left:0;pointer-events:none;z-index:0}.snowflake{position:absolute;top:-24px;display:inline-block;color:#fffffff2;line-height:1;animation:snowfall linear infinite;text-shadow:0 0 3px rgba(255,255,255,.4)}@keyframes snowfall{to{transform:translateY(100vh) rotate(360deg)}}.branch-footer{padding:1.5rem 0;display:flex;justify-content:center;position:relative;z-index:10}.branch-demo-box{display:flex;align-items:center;gap:12px;padding:8px 16px;background:#0009;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);border-radius:12px;border:1px solid rgba(255,255,255,.1)}.branch-demo-label{font-size:.85rem;font-weight:600;color:#fff}.branch-demo-btns{display:flex;gap:6px}.branch-demo-btns button{width:36px;height:36px;border-radius:8px;border:2px solid rgba(255,255,255,.3);background:#ffffff1a;color:#fff;font-size:1rem;font-weight:600;cursor:pointer;transition:all .2s}.branch-demo-btns button:hover{background:#fff3;border-color:#ffffff80}.branch-demo-btns button.active{background:var(--accent-light);border-color:var(--accent-light);color:#0d2a12}.branch-header,.branch-tree-container,.branch-categories{position:relative;z-index:1}.branch-header{text-align:center;margin-bottom:.5rem;flex-shrink:0;padding-top:.75rem;display:flex;flex-direction:column;align-items:center;gap:.5rem}.branch-header-top{display:flex;align-items:center;justify-content:center;gap:.5rem;flex-wrap:wrap}.branch-level-badge{font-size:.8rem;font-weight:600;padding:.25rem .6rem;border-radius:8px;background:#ffffff26;color:var(--accent-bright);border:1px solid rgba(255,255,255,.2)}.branch-logo{color:var(--accent-light)}.branch-progress-bar{height:6px;background:var(--bg-card);border-radius:3px;overflow:hidden;max-width:280px;margin:0 auto}.branch-progress-fill{height:100%;background:var(--accent-light);border-radius:3px;transition:width .3s ease}.branch-tree-container{flex:1;min-height:0;display:flex;align-items:center;justify-content:center;padding:0 1rem;overflow:hidden}.branch-tree-svg{width:auto;max-width:100%;height:100%;max-height:min(55vh,380px);object-fit:contain}.branch-categories{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin-top:0;flex-shrink:0;padding:0;width:100%;max-width:320px;margin-left:auto;margin-right:auto;box-sizing:border-box}.category-btn{height:80px;background:#1a2e2280;backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);border:1px solid var(--border-subtle);border-radius:10px;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:.5rem;gap:.25rem;transition:transform .15s ease,border-color .2s ease,box-shadow .3s ease}.category-btn.active{border-color:#7da88280;box-shadow:0 0 24px #7da88240,inset 0 0 0 1px #7da88226}.category-btn.active.basics-active{border-color:#7da88299;box-shadow:0 0 28px #7da8824d,inset 0 0 0 1px #7da88233}.category-btn:not(.locked):hover{transform:scale(1.03);border-color:var(--accent-light)}.category-btn:not(.locked):active{transform:scale(.98)}.category-btn.locked{opacity:.7;cursor:not-allowed}.category-lock{position:absolute;top:.4rem;right:.4rem;color:var(--lock-gold)}.category-btn{position:relative}.category-icon{display:flex;align-items:center;justify-content:center;flex-shrink:0}.category-icon svg{width:28px;height:28px}.category-dots{display:flex;gap:4px;align-items:center;justify-content:center}.category-dot{width:6px;height:6px;border-radius:50%;background:#fff3;transition:background .3s ease}.category-dot.done{background:var(--accent-light)}@media (min-width: 640px){.branch-categories{max-width:360px}}.branch-header{position:relative;z-index:10}.branch-demo-link{display:inline-block;font-size:.75rem;font-weight:700;color:#0d2a12;background:var(--accent-light);padding:4px 12px;border-radius:6px;text-decoration:none;border:1px solid rgba(255,255,255,.4);box-shadow:0 2px 8px #00000026;transition:all .2s ease;margin-left:8px;text-transform:uppercase;letter-spacing:.05em}.branch-demo-link:hover{transform:translateY(-1px);box-shadow:0 4px 12px #7da8824d;background:#fff}.voice-screen{height:100vh;height:100dvh;width:100%;padding:1rem 1.25rem;display:flex;flex-direction:column;align-items:center;justify-content:flex-start;background:linear-gradient(180deg,#020f0b,#031b14 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50%);pointer-events:none;z-index:0}.voice-stage{width:100%;max-width:min(340px,92vw);display:flex;flex-direction:column;align-items:center;justify-content:center;position:relative;z-index:1;flex:1;min-height:0;gap:0}.voice-interaction{display:flex;flex-direction:column;align-items:center;width:100%;max-width:280px;gap:1.25rem;flex-shrink:0}.voice-header{width:100%;max-width:280px;display:flex;align-items:center;justify-content:space-between;margin-bottom:.75rem;z-index:3;flex-shrink:0}.voice-back,.voice-speaker{color:#ffffffa6;padding:.5rem;margin:-.5rem;display:flex;align-items:center;justify-content:center;border-radius:14px;transition:color .2s ease,background .2s ease,transform .15s cubic-bezier(.34,1.56,.64,1)}.voice-back:hover,.voice-speaker:hover{color:#fff;background:#ffffff14}.voice-speaker:disabled{opacity:.5;cursor:not-allowed}.voice-back:active,.voice-speaker:active{transform:scale(.94)}.voice-dots{display:flex;gap:.5rem}.voice-dot{width:6px;height:6px;border-radius:50%;background:#fff3;transition:all .3s cubic-bezier(.34,1.56,.64,1)}.voice-dot.active{background:#e88d4a;box-shadow:0 0 14px #e88d4a8c;transform:scale(1.1)}.voice-timer{font-family:Inter,-apple-system,BlinkMacSystemFont,sans-serif;font-size:clamp(3rem,10vw,4.5rem);font-weight:200;letter-spacing:.06em;color:#fffffffa;text-align:center;margin-bottom:1.25rem;z-index:3;flex-shrink:0;text-shadow:0 0 48px rgba(125,184,122,.45),0 0 24px rgba(125,184,122,.25)}.voice-timer--listen{display:flex;align-items:center;justify-content:center;color:#ffffffe6}.voice-card{width:100%;max-width:280px;background:linear-gradient(135deg,#ffffff0f,#ffffff05);backdrop-filter:blur(28px);-webkit-backdrop-filter:blur(28px);border:1px solid rgba(255,255,255,.1);border-radius:20px;padding:1.25rem;display:flex;flex-direction:column;align-items:center;gap:1rem;margin-bottom:0;position:relative;flex-shrink:0;z-index:2;box-shadow:0 8px 40px #00000059,0 0 0 1px #ffffff0f inset;transition:all .35s cubic-bezier(.34,1.56,.64,1)}.voice-card:hover{border-color:#ffffff24;box-shadow:0 12px 48px #0006,0 0 0 1px #ffffff14 inset}.voice-card-glow{position:absolute;top:-20px;right:-20px;bottom:-20px;left:-20px;border-radius:32px;background:radial-gradient(circle at 50% 50%,rgba(125,184,122,.12) 0%,rgba(125,184,122,.04) 50%,transparent 75%);pointer-events:none;z-index:-1}.voice-avatar-wrap{position:relative}.voice-avatar-wrap:before{content:"";position:absolute;top:-6px;right:-6px;bottom:-6px;left:-6px;border-radius:50%;border:2px solid rgba(232,141,74,.6);box-shadow:0 0 28px #e88d4a66,0 0 56px #e88d4a26;animation:avatar-ring-pulse 2.8s ease-in-out infinite}.voice-avatar{width:52px;height:52px;color:#e88d4a;position:relative;z-index:1}.voice-avatar svg{width:100%;height:100%;filter:drop-shadow(0 2px 8px rgba(232,141,74,.3))}@keyframes avatar-ring-pulse{0%,to{opacity:.75;transform:scale(1)}50%{opacity:1;transform:scale(1.03)}}.voice-waveform{display:flex;align-items:flex-end;justify-content:center;gap:4px;height:40px}.voice-bar{width:4px;min-height:8px;max-height:40px;background:linear-gradient(180deg,#e88d4a99,#e88d4af2,#e88d4ab3);border-radius:6px;align-self:flex-end;box-shadow:0 0 12px #e88d4a33}.voice-prompt{font-family:Inter,-apple-system,sans-serif;font-size:.8rem;font-weight:400;line-height:1.4;color:#fff9;margin:0 0 .5rem;font-style:italic}.voice-phrase{font-family:Inter,-apple-system,sans-serif;font-size:.95rem;font-weight:400;line-height:1.55;color:#ffffffeb;text-align:center;max-width:100%;margin:0;letter-spacing:.02em}.voice-bengali-block{margin-top:.5rem;text-align:center}.voice-phrase-bengali{font-size:.88rem;line-height:1.45;color:#ffffffbf;text-align:center;margin:0;letter-spacing:.02em}.voice-phrase-pronunciation{font-size:.8rem;line-height:1.4;color:#fff9;font-style:italic;text-align:center;margin:.25rem 0 0}.voice-bengali-listen{display:inline-block;margin-top:.5rem;padding:.35rem .75rem;font-size:.8rem;color:#ffffffe6;background:#ffffff1f;border:1px solid rgba(255,255,255,.2);border-radius:999px;cursor:pointer;transition:background .2s,border-color .2s}.voice-bengali-listen:hover{background:#ffffff2e;border-color:#ffffff4d}.voice-feedback{margin-top:.75rem;padding:.6rem .75rem;border-radius:12px;background:#ffffff0f;border:1px solid rgba(255,255,255,.1);width:100%;text-align:left}.voice-you-said{font-size:.85rem;color:#ffffffb3;margin:0 0 .35rem}.voice-loading{font-size:.9rem;color:#fff9;margin:0;font-style:italic}.voice-answer{font-size:.9rem;color:#7db87af2;margin:0;line-height:1.4}.voice-answer-incorrect{color:#ffb4a0fa;font-weight:600}.voice-feedback-incorrect{border-color:#ff786459;background:#ff645014}.voice-mic-section{display:flex;flex-direction:column;align-items:center;gap:.75rem;margin-bottom:0;position:relative;z-index:2;flex-shrink:0}.voice-mic-glow{position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);width:280px;height:280px;border-radius:50%;background:radial-gradient(circle at 50% 50%,rgba(125,184,122,.18) 0%,rgba(125,184,122,.08) 40%,rgba(125,184,122,.03) 65%,transparent 80%);pointer-events:none;z-index:-1}.voice-mic-section:has(.voice-mic-btn.recording) .voice-mic-glow{background:radial-gradient(circle at 50% 50%,rgba(232,100,80,.22) 0%,rgba(232,100,80,.1) 40%,rgba(232,100,80,.04) 65%,transparent 80%)}.voice-mic-btn{width:160px;height:160px;border-radius:50%;border:2px solid rgba(255,255,255,.14);background:radial-gradient(circle at 50% 50%,#ffffff1a,#ffffff08);backdrop-filter:blur(20px);-webkit-backdrop-filter:blur(20px);display:flex;align-items:center;justify-content:center;cursor:pointer;position:relative;transition:border-color .3s ease,box-shadow .35s ease;box-shadow:0 12px 40px #0006,0 0 0 1px #ffffff12 inset}.voice-mic-btn:before{content:"";position:absolute;top:-14px;right:-14px;bottom:-14px;left:-14px;border-radius:50%;border:2px solid rgba(125,184,122,.35);animation:mic-ring-pulse 2.8s ease-in-out infinite;pointer-events:none}.voice-mic-btn:after{content:"";position:absolute;top:-24px;right:-24px;bottom:-24px;left:-24px;border-radius:50%;border:1px solid rgba(125,184,122,.15);animation:mic-ring-pulse 2.8s ease-in-out infinite .7s;pointer-events:none}@keyframes mic-ring-pulse{0%,to{transform:scale(1);opacity:.65}50%{transform:scale(1.08);opacity:.2}}.voice-mic-btn:hover{border-color:#7db87a66;box-shadow:0 16px 48px #00000073,0 0 56px #7db87a40,0 0 0 1px #ffffff1a inset}.voice-mic-btn:active{transform:scale(.96)}.voice-mic-btn:disabled{cursor:not-allowed;opacity:.9}.voice-mic-btn.recording{border-color:#e8645080;background:radial-gradient(circle at 50% 50%,#e864501f,#ffffff08);box-shadow:0 12px 40px #0006,0 0 64px #e8645073,0 0 0 1px #e8645040 inset}.voice-mic-btn.recording:before{border-color:#e8645080;animation:mic-ring-recording 1.1s ease-in-out infinite}.voice-mic-btn.recording:after{border-color:#e8645038;animation:mic-ring-recording 1.1s ease-in-out infinite .3s}@keyframes mic-ring-recording{0%,to{transform:scale(1);opacity:.8}50%{transform:scale(1.12);opacity:.35}}.voice-mic-icon{display:flex;align-items:center;justify-content:center;color:#fffffff2;filter:drop-shadow(0 2px 8px rgba(0,0,0,.3));transition:filter .3s ease}.voice-mic-btn:hover .voice-mic-icon{filter:drop-shadow(0 0 16px rgba(125,184,122,.45))}.voice-mic-btn.recording .voice-mic-icon{filter:drop-shadow(0 0 20px rgba(232,100,80,.55))}.voice-status-dots{display:flex;gap:8px;align-items:center}.voice-status-dot{width:6px;height:6px;border-radius:50%;background:#ffffff38;flex-shrink:0;transition:all .3s ease}.voice-status-dot.active{background:#7db87af2;box-shadow:0 0 12px #7db87aa6}.voice-footer{width:auto;z-index:3;flex-shrink:0}.voice-next-btn{width:auto;min-width:120px;height:44px;padding:0 1.5rem;background:#ffffff0f;backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);border:1px solid rgba(255,255,255,.1);border-radius:22px;color:#ffffffe6;font-family:Inter,-apple-system,sans-serif;font-size:.9rem;font-weight:500;display:flex;align-items:center;justify-content:center;gap:.375rem;cursor:pointer;transition:all .25s ease;box-shadow:0 2px 16px #0003,0 0 0 1px #ffffff08 inset}.voice-next-btn:hover{background:#ffffff1a;border-color:#7db87a59;box-shadow:0 0 24px #7db87a26,0 0 0 1px #ffffff0d inset}.voice-next-btn:active{transform:scale(.98)}.voice-next-btn:disabled{opacity:.5;cursor:not-allowed;pointer-events:none}@media (min-width: 640px){.voice-screen{padding:1.5rem 2rem}.voice-screen:before{width:min(85vw,640px)}.voice-stage{max-width:min(380px,92vw)}.voice-interaction{max-width:320px;gap:1.5rem}.voice-header,.voice-card{max-width:320px}.voice-timer{margin-bottom:1.75rem;font-size:clamp(3.5rem,8vw,4.5rem)}.voice-timer--listen{font-size:clamp(2.75rem,6vw,3.25rem)}.voice-card{padding:1.5rem;border-radius:22px;gap:1rem}.voice-avatar{width:56px;height:56px}.voice-waveform{height:44px}.voice-bar{width:5px;max-height:44px}.voice-phrase{font-size:1rem}.voice-mic-section{gap:.75rem}.voice-mic-glow{width:300px;height:300px}.voice-mic-btn{width:170px;height:170px}.voice-next-btn{height:46px;padding:0 1.75rem;border-radius:23px}}@media (min-width: 768px){.voice-screen{padding:1.75rem 2.5rem}.voice-stage{max-width:min(400px,90vw)}.voice-interaction,.voice-header,.voice-card{max-width:360px}.voice-timer{margin-bottom:1.5rem}}@media (min-width: 1024px){.voice-screen{padding:1.5rem 3rem;justify-content:center}.voice-screen:before{width:min(95vw,1100px);height:85vh}.voice-stage{max-width:min(440px,90vw);gap:0;flex:1;min-height:0;justify-content:center}.voice-interaction{max-width:380px;gap:1.5rem}.voice-header,.voice-card{max-width:380px}.voice-header{margin-bottom:1rem;flex-shrink:0}.voice-timer{margin-bottom:1.5rem;font-size:5rem;font-weight:100;letter-spacing:.18em;flex-shrink:0}.voice-timer--listen{font-size:3.25rem;letter-spacing:.2em}.voice-card{padding:1.5rem 1.75rem;border-radius:24px;gap:1rem}.voice-card-glow{top:-24px;right:-24px;bottom:-24px;left:-24px;border-radius:32px}.voice-avatar{width:60px;height:60px}.voice-avatar-wrap:before{top:-7px;right:-7px;bottom:-7px;left:-7px}.voice-waveform{height:48px;gap:5px}.voice-bar{width:5px;max-height:48px}.voice-phrase{font-size:1.1rem;line-height:1.55}.voice-mic-section{gap:.875rem;flex-shrink:0}.voice-mic-glow{width:340px;height:340px}.voice-mic-btn{width:200px;height:200px}.voice-mic-btn:before{top:-22px;right:-22px;bottom:-22px;left:-22px}.voice-mic-btn:after{top:-38px;right:-38px;bottom:-38px;left:-38px}.voice-next-btn{height:48px;padding:0 2rem;border-radius:24px;font-size:.95rem}}@media (min-width: 1280px){.voice-screen{padding:2rem 4rem}.voice-stage{max-width:min(460px,85vw)}.voice-interaction{max-width:400px;gap:1.75rem}.voice-header,.voice-card{max-width:400px}.voice-timer{font-size:5.5rem}.voice-timer--listen{font-size:3.5rem}.voice-card{padding:1.75rem 2rem}.voice-phrase{font-size:1.15rem}.voice-mic-btn{width:220px;height:220px}.voice-mic-glow{width:380px;height:380px}}:root{--bg-dark: #0f2419;--bg-card: #1a2e22;--accent-light: #5a8f5a;--accent-bright: #7ab87a;--accent-teal: #4a8a82;--accent-orange: #c49a4a;--accent-blue: #5a7a8a;--accent-purple: #6b5b7a;--text-light: #e8f0e8;--text-muted: #8a9e8a;--lock-gold: #c9a855;--bark-dark: #4a3828;--bark-warm: #6b5344;--bark-light: #8b7355;--border-subtle: rgba(90, 143, 90, .2)}*{margin:0;padding:0;box-sizing:border-box}html,body{height:100%;overflow-x:hidden}body{font-family:Nunito,-apple-system,BlinkMacSystemFont,sans-serif;background:var(--bg-dark);color:var(--text-light);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}h1,h2,.branch-title,.phrase-text{font-family:Lora,Georgia,serif}#root{min-height:100%;width:100%;max-width:100%;margin:0 auto;position:relative}button{font-family:inherit;cursor:pointer;border:none;background:none}button:focus-visible{outline:2px solid var(--accent-light);outline-offset:2px}@media (hover: none){button,a{min-height:44px;min-width:44px}}