:root{--bg-deep: #020617;--bg-main: #0f172a;--surface: rgba(15, 23, 42, .7);--surface-hover: rgba(30, 41, 59, .8);--border: rgba(148, 163, 184, .1);--accent: #38bdf8;--accent-glow: rgba(56, 189, 248, .4);--indigo: #6366f1;--text-primary: #f8fafc;--text-secondary: #94a3b8;--text-muted: #64748b;--glass-blur: 12px;--card-shadow: 0 10px 40px -10px rgba(0, 0, 0, .6)}body{background:radial-gradient(circle at 50% 0%,#1e293b,#020617);background-color:var(--bg-deep);font-family:Plus Jakarta Sans,sans-serif;color:var(--text-primary);margin:0;padding:0;min-height:100vh}header{padding:1rem}.floating-navbar{position:fixed;top:20px;left:50%;transform:translate(-50%);width:95%;max-width:380px;display:flex;justify-content:center;z-index:2000;pointer-events:none}.segmented-control{display:flex;width:100%;justify-content:space-between;background:#0f172a99;backdrop-filter:blur(var(--glass-blur));-webkit-backdrop-filter:blur(var(--glass-blur));border:1px solid var(--border);border-radius:50px;padding:6px;box-shadow:0 20px 50px -10px #00000080,0 0 20px var(--accent-glow);pointer-events:auto}.segment-item{padding:10px 12px;text-decoration:none;color:var(--text-secondary);font-size:.9rem;font-weight:600;border-radius:40px;transition:all .4s cubic-bezier(.23,1,.32,1);display:flex;align-items:center;justify-content:center;gap:8px;flex:1}.segment-item:hover{color:var(--text-primary);background:#ffffff0d}.segment-item.active{background:var(--accent);color:#020617;box-shadow:0 0 25px var(--accent-glow)}.nav-icon{font-size:1.1rem}.container{display:flex;flex-direction:column;align-items:center;padding-top:150px;padding-bottom:3rem}.grade-nav-container{position:fixed;top:95px;left:50%;transform:translate(-50%);width:95%;max-width:380px;display:flex;justify-content:center;z-index:1000}.grade-tabs{display:flex;width:100%;gap:4px;background:#0f172a66;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);padding:6px;border-radius:50px;border:1px solid var(--border);justify-content:space-around}.grade-tab-item{padding:8px 10px;border-radius:30px;border:1px solid transparent;background:transparent;color:var(--text-secondary);font-size:.8rem;font-weight:700;cursor:pointer;white-space:nowrap;transition:all .3s;flex:1;text-align:center;display:flex;align-items:center;justify-content:center}.grade-tab-item:hover{color:var(--text-primary);background:#ffffff0d}.grade-tab-item.active{background:var(--surface);color:var(--accent);border-color:var(--accent);box-shadow:0 0 15px var(--accent-glow)}.grid-container{display:flex;flex-wrap:wrap;justify-content:center;gap:20px;width:100%;max-width:600px;margin:0 auto}.item{display:flex;flex-direction:column;align-items:center;justify-content:center;margin:10px 0;transition:all .3s cubic-bezier(.4,0,.2,1);width:110px;cursor:pointer}.item p{margin:10px 0 0;text-align:center;font-size:14px;font-weight:700;color:var(--text-secondary);line-height:1.4;transition:color .3s}.item:hover p{color:var(--text-primary)}img{border-radius:24px;width:80px;height:80px;background:var(--surface);border:2px solid var(--border);cursor:pointer;transition:all .4s cubic-bezier(.34,1.56,.64,1);box-shadow:0 8px 25px #0006;object-fit:contain}.item:hover img{border-color:var(--accent);transform:translateY(-5px) scale(1.05);box-shadow:0 10px 25px -5px var(--accent-glow)}img:active{transform:scale(.95)}.subtitle{margin-top:20px;margin-bottom:10px;color:var(--text-muted);font-weight:600;letter-spacing:.05em}.home-title{font-size:1.8rem;font-weight:800;color:var(--text-primary);margin-bottom:0;margin-top:35px;background:linear-gradient(to right,#f8fafc,#38bdf8);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent;letter-spacing:-.02em}.grade-section{width:100%;margin-bottom:40px}.grade-header{font-size:1.5rem;font-weight:800;color:var(--accent);padding:15px 20px;background:#0f172acc;-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border-radius:12px;border-left:4px solid var(--accent);position:sticky;top:80px;z-index:10;text-align:left;width:calc(100% - 40px);max-width:320px;margin:20px auto}.theme-group{margin-bottom:30px}.theme-title{font-size:1.1rem;font-weight:700;color:var(--text-secondary);margin:15px 0 10px;text-align:center;text-transform:uppercase;letter-spacing:.1em}.search-container{width:100%;margin-top:50px;margin-bottom:50px;text-align:center}.dark-button{padding:8px 12px;border-radius:8px;border:1px solid var(--border);background:var(--surface);color:var(--text-primary);font-family:inherit;cursor:pointer;margin-left:5px;transition:all .3s;-webkit-backdrop-filter:blur(5px);backdrop-filter:blur(5px)}.search-input:focus{border-color:var(--accent);box-shadow:0 0 15px var(--accent-glow);background:var(--surface-hover);outline:none}.round-img{object-fit:contain}.image-fallback{display:none;width:50px;height:50px;border-radius:16px;background:var(--surface);color:var(--text-muted);font-size:9px;justify-content:center;align-items:center;text-align:center;line-height:1.2;border:1px solid var(--border)}.dark-button:hover{background:var(--surface-hover);border-color:#fff3}.challenge-body{background:var(--bg-deep);background:radial-gradient(circle at 50% 50%,#1e293b,#020617);display:flex;flex-direction:column;align-items:center;justify-content:center;height:100vh;margin:0}.challenge-container{display:flex;flex-direction:column;align-items:center;width:100%}.challenge-container h1{font-size:1.5rem;font-weight:700;color:var(--accent);margin:0 0 10px;text-align:center;line-height:1.2}.challenge-index{font-size:1rem;font-weight:600;color:var(--text-muted);margin-bottom:10px}.challenge-card{font-size:2.2rem;padding:30px 20px;background:var(--surface);-webkit-backdrop-filter:blur(var(--glass-blur));backdrop-filter:blur(var(--glass-blur));border:1px solid rgba(255,255,255,.1);border-radius:32px;text-align:center;box-shadow:var(--card-shadow),inset 0 0 20px #ffffff0d;width:90%;max-width:300px;color:var(--text-primary);cursor:pointer;display:flex;flex-direction:column;gap:15px;transition:all .4s cubic-bezier(.23,1,.32,1)}.challenge-card:hover{border-color:#38bdf84d;box-shadow:var(--card-shadow),0 0 30px #38bdf81a}.word-en{font-weight:800;letter-spacing:-.01em;animation:glow-pulse 2s infinite ease-in-out}.word-ko{font-size:1.4rem;font-weight:700;color:#fbbf24;text-shadow:0 0 20px rgba(251,191,36,.3)}@keyframes glow-pulse{0%{opacity:.7;filter:drop-shadow(0 0 0px var(--accent-glow))}50%{opacity:1;filter:drop-shadow(0 0 8px var(--accent-glow))}to{opacity:.7;filter:drop-shadow(0 0 0px var(--accent-glow))}}.challenge-image{margin:15px auto 0;width:240px;height:240px;max-width:90%;aspect-ratio:1 / 1;background:#020617;border:1px solid var(--border);border-radius:24px;display:flex;align-items:center;justify-content:center;overflow:hidden;box-shadow:inset 0 0 30px #00000080}.word-image{width:100%;height:100%;object-fit:cover}.no-image{font-size:.9rem;color:var(--text-muted)}.challenge-controls{margin:25px auto 0;display:flex;flex-wrap:nowrap;gap:8px;justify-content:center;width:100%;max-width:310px}.challenge-controls button{padding:10px 4px;font-family:inherit;font-size:.85rem;font-weight:700;cursor:pointer;background:var(--surface);border:1px solid var(--border);border-radius:12px;color:var(--text-primary);transition:all .3s cubic-bezier(.23,1,.32,1);flex:1;min-width:0;white-space:nowrap;-webkit-backdrop-filter:blur(5px);backdrop-filter:blur(5px)}.challenge-controls button:hover{background:var(--surface-hover);border-color:var(--accent);color:var(--accent);transform:translateY(-2px);box-shadow:0 5px 15px #0000004d}.stt-controls{margin-top:15px;width:100%;display:flex;flex-direction:column;align-items:center}.mic-button{padding:15px 30px;font-family:inherit;font-size:1.1rem;font-weight:800;border-radius:100px;border:none;background:linear-gradient(135deg,#ef4444,#b91c1c);color:#fff;cursor:pointer;box-shadow:0 10px 25px -5px #ef444466;transition:all .3s cubic-bezier(.23,1,.32,1);display:flex;align-items:center;gap:10px}.mic-button:hover:not(:disabled){transform:translateY(-3px) scale(1.02);box-shadow:0 15px 30px -5px #ef444499}.mic-button.listening{background:linear-gradient(135deg,#22c55e,#15803d);box-shadow:0 0 30px #22c55e80;animation:pulse-active 1.5s infinite}@keyframes pulse-active{0%{transform:scale(1)}50%{transform:scale(1.05)}to{transform:scale(1)}}.mic-hint{font-size:.75rem;font-weight:600;color:var(--text-muted);margin-top:8px;letter-spacing:.02em}.stt-feedback{margin-top:15px;padding:10px 20px;border-radius:16px;font-weight:700;text-align:center;animation:slideUp .4s cubic-bezier(.23,1,.32,1)}.level-3{background:#22c55e33;color:#4ade80;border:1px solid rgba(74,222,128,.3)}.level-2{background:#f59e0b33;color:#fbbf24;border:1px solid rgba(251,191,36,.3)}.level-1{background:#64748b33;color:#cbd5e1;border:1px solid rgba(203,213,225,.3)}.scrambled-hint{display:flex;flex-wrap:wrap;gap:8px;justify-content:center;margin-bottom:20px;margin-top:10px}.letter-card{background:var(--surface);color:var(--text-primary);padding:10px 15px;border-radius:12px;font-size:1.2rem;font-weight:700;cursor:pointer;border:1px solid var(--border);transition:all .3s cubic-bezier(.23,1,.32,1);-webkit-user-select:none;user-select:none;box-shadow:0 4px 10px #0000004d}.letter-card:hover{background:var(--surface-hover);border-color:var(--accent);transform:translateY(-3px);box-shadow:0 10px 20px -5px var(--accent-glow)}.letter-card:active{transform:translateY(0)}.scramble-input{background:#02061766;border:1px solid var(--border);color:var(--text-primary);padding:15px;border-radius:16px;width:240px;font-family:inherit;font-size:1.4rem;font-weight:800;text-align:center;outline:none;margin-top:20px;transition:all .3s;letter-spacing:.1em}.scramble-input:focus{border-color:var(--accent);box-shadow:0 0 20px var(--accent-glow);background:#02061799}.scramble-game .word-ko{font-size:1.8rem;margin-bottom:20px;color:var(--accent);font-weight:800}.scramble-game .check-btn{background:var(--accent)!important;color:#020617!important;border:none!important}.scramble-game .reset-input{background:var(--surface)!important}.scramble-spinner{width:40px;height:40px;border:3px solid rgba(56,189,248,.1);border-top:3px solid var(--accent);border-radius:50%;animation:spin .8s linear infinite;margin-bottom:10px}@keyframes spin{to{transform:rotate(360deg)}}.fade-in{animation:fadeIn .6s cubic-bezier(.23,1,.32,1) forwards}@keyframes fadeIn{0%{opacity:0;transform:translateY(10px) scale(.98)}to{opacity:1;transform:translateY(0) scale(1)}}.scramble-image-area-inline{width:100%;display:flex;justify-content:center;transition:all .5s ease;overflow:hidden;margin:0 auto}.spinner-container{display:flex;flex-direction:column;align-items:center;justify-content:center;height:240px;color:var(--text-muted)}.image-scramble-inline{margin-top:10px;margin-bottom:10px}.scramble-button-group{display:flex;gap:10px;margin-top:10px;flex-wrap:wrap;justify-content:center}.view-img-btn-inline{padding:8px 18px;font-family:inherit;font-size:.95rem;font-weight:700;background:var(--surface)!important;border:1px solid var(--border);border-radius:20px;transition:all .3s cubic-bezier(.23,1,.32,1);width:100%;max-width:200px;margin-top:5px}