:root{--color-primary: #4f46e5;--color-primary-light: #6366f1;--color-primary-dark: #4338ca;--color-primary-bg: #eef2ff;--color-secondary: #10b981;--color-secondary-bg: #ecfdf5;--color-accent: #f59e0b;--color-accent-bg: #fffbeb;--color-danger: #ef4444;--color-danger-bg: #fef2f2;--color-success: #22c55e;--color-success-bg: #f0fdf4;--color-bg: #f1f5f9;--color-surface: #ffffff;--color-text: #1e293b;--color-text-secondary: #64748b;--color-text-muted: #94a3b8;--color-border: #e2e8f0;--color-border-light: #f1f5f9;--color-dark: #1f2937;--shadow-sm: 0 1px 3px rgba(0, 0, 0, .04);--shadow-md: 0 4px 20px -2px rgba(0, 0, 0, .06);--shadow-lg: 0 10px 40px -4px rgba(0, 0, 0, .1);--shadow-button: 0 4px 0 0 var(--color-primary-dark);--radius-sm: .75rem;--radius-md: 1rem;--radius-lg: 1.5rem;--radius-xl: 2rem;--radius-full: 9999px;--font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;--font-size-xs: .625rem;--font-size-sm: .75rem;--font-size-base: .875rem;--font-size-md: 1rem;--font-size-lg: 1.125rem;--font-size-xl: 1.25rem;--font-size-2xl: 1.5rem;--font-size-3xl: 1.875rem;--space-1: .25rem;--space-2: .5rem;--space-3: .75rem;--space-4: 1rem;--space-5: 1.25rem;--space-6: 1.5rem;--space-8: 2rem;--transition-fast: .15s ease;--transition-normal: .25s ease;--transition-slow: .4s ease-out}*,*:before,*:after{margin:0;padding:0;box-sizing:border-box}html{-webkit-tap-highlight-color:transparent;-webkit-text-size-adjust:100%}body{font-family:var(--font-family);font-size:var(--font-size-base);color:var(--color-text);background-color:var(--color-bg);line-height:1.5;min-height:100dvh;overflow-x:hidden;-webkit-font-smoothing:antialiased}#app{max-width:480px;margin:0 auto;min-height:100dvh;position:relative;background:var(--color-bg)}img{max-width:100%;display:block}button{cursor:pointer;border:none;background:none;font:inherit;color:inherit}input{font:inherit;border:none;outline:none}a{text-decoration:none;color:inherit}.page-content{padding:var(--space-6);padding-bottom:100px}.app-header{background:var(--color-surface);padding:var(--space-8) var(--space-6) var(--space-6);border-radius:0 0 var(--radius-xl) var(--radius-xl);box-shadow:var(--shadow-sm)}.header-row{display:flex;align-items:center;justify-content:space-between}.user-info{display:flex;align-items:center;gap:var(--space-4)}.user-avatar{width:56px;height:56px;border-radius:var(--radius-full);border:2.5px solid var(--color-primary-bg);object-fit:cover;background:linear-gradient(135deg,var(--color-primary-bg),#dbeafe);display:flex;align-items:center;justify-content:center;font-size:1.5rem;position:relative}.user-avatar .online-dot{position:absolute;bottom:-2px;right:-2px;width:14px;height:14px;background:var(--color-success);border-radius:var(--radius-full);border:2.5px solid var(--color-surface)}.user-name{font-size:var(--font-size-xl);font-weight:800;color:var(--color-text)}.level-badge{display:inline-flex;align-items:center;gap:var(--space-2);margin-top:2px}.level-tag{font-size:var(--font-size-xs);font-weight:700;padding:2px 8px;background:var(--color-primary-bg);color:var(--color-primary);border-radius:var(--radius-full)}.level-text{font-size:var(--font-size-xs);color:var(--color-text-muted)}.icon-btn{width:40px;height:40px;display:flex;align-items:center;justify-content:center;background:var(--color-bg);border-radius:var(--radius-full);color:var(--color-text-secondary);transition:background var(--transition-fast)}.icon-btn:hover{background:var(--color-border)}.card{background:var(--color-surface);border-radius:var(--radius-xl);padding:var(--space-5);box-shadow:var(--shadow-md)}.card-bordered{border:2px solid var(--color-border-light)}.streak-card{display:flex;align-items:center;justify-content:space-between}.streak-info{display:flex;align-items:center;gap:var(--space-4)}.streak-icon{background:var(--color-accent-bg);padding:var(--space-3);border-radius:var(--radius-md);color:var(--color-accent);display:flex}.streak-label{font-size:var(--font-size-sm);color:var(--color-text-muted);font-weight:500}.streak-value{font-size:var(--font-size-xl);font-weight:800;color:var(--color-text)}.streak-bars{display:flex;gap:5px;align-items:flex-end}.streak-bar{width:5px;border-radius:var(--radius-full);transition:height var(--transition-slow)}.continue-card{background:linear-gradient(135deg,var(--color-primary),var(--color-primary-light));border-radius:2rem;padding:var(--space-6);position:relative;overflow:hidden;box-shadow:var(--shadow-lg)}.continue-card .bg-circle{position:absolute;top:0;right:0;width:120px;height:120px;background:#ffffff14;border-radius:var(--radius-full);transform:translate(40%,-40%)}.continue-card .content{position:relative;z-index:1}.continue-card .category{font-size:var(--font-size-xs);font-weight:700;color:#ffffffb3;text-transform:uppercase;letter-spacing:.15em}.continue-card .title{font-size:var(--font-size-2xl);font-weight:800;color:#fff;margin-top:4px;margin-bottom:var(--space-4)}.progress-row{display:flex;align-items:center;gap:var(--space-3);margin-bottom:var(--space-6)}.progress-track{flex:1;height:8px;background:#ffffff40;border-radius:var(--radius-full);overflow:hidden}.progress-fill{height:100%;background:#fff;border-radius:var(--radius-full);transition:width .8s 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2px}.section-title{font-size:var(--font-size-lg);font-weight:800;color:var(--color-text)}.section-link{font-size:var(--font-size-sm);font-weight:600;color:var(--color-primary)}.flashcard{display:flex;flex-direction:column;align-items:center;text-align:center;padding:var(--space-6)}.flashcard .badge{font-size:var(--font-size-xs);font-weight:700;padding:4px 12px;background:var(--color-primary-bg);color:var(--color-primary);border-radius:var(--radius-sm);text-transform:uppercase;letter-spacing:.12em;margin-bottom:var(--space-3)}.flashcard .word{font-size:var(--font-size-3xl);font-weight:900;color:var(--color-text);margin-bottom:4px}.flashcard .phonetic{font-size:var(--font-size-base);color:var(--color-text-muted);font-style:italic;margin-bottom:var(--space-4)}.flashcard .definition{font-size:var(--font-size-base);color:var(--color-text-secondary);line-height:1.6}.flashcard-actions{display:flex;gap:var(--space-3);width:100%;margin-top:var(--space-6)}.btn-outline{flex:1;display:flex;align-items:center;justify-content:center;gap:var(--space-2);padding:12px;border:2px solid var(--color-border-light);border-radius:var(--radius-md);font-weight:600;color:var(--color-text-muted);transition:all var(--transition-fast)}.btn-outline:hover{border-color:var(--color-primary-bg);color:var(--color-primary)}.btn-dark{flex:1;padding:12px;background:var(--color-dark);color:#fff;font-weight:600;border-radius:var(--radius-md);transition:all var(--transition-fast)}.btn-dark:active{transform:scale(.97)}.search-bar{position:relative;margin-bottom:var(--space-4)}.search-bar input{width:100%;padding:12px 12px 12px 44px;background:var(--color-bg);border-radius:var(--radius-xl);font-size:var(--font-size-sm);color:var(--color-text);transition:all var(--transition-fast)}.search-bar input:focus{background:var(--color-surface);box-shadow:0 0 0 2px var(--color-primary-bg)}.search-bar .search-icon{position:absolute;left:14px;top:50%;transform:translateY(-50%);color:var(--color-text-muted)}.quiz-list-card{background:var(--color-surface);border-radius:var(--radius-md);padding:var(--space-4);display:flex;align-items:center;gap:var(--space-4);box-shadow:var(--shadow-sm);border:1px solid var(--color-border-light);transition:transform var(--transition-fast)}.quiz-list-card:active{transform:scale(.98)}.quiz-icon{width:56px;height:56px;border-radius:var(--radius-sm);display:flex;align-items:center;justify-content:center;flex-shrink:0;font-size:1.5rem}.quiz-info{flex:1;min-width:0}.quiz-info h3{font-size:var(--font-size-base);font-weight:700;color:var(--color-text)}.quiz-info p{font-size:var(--font-size-xs);color:var(--color-text-muted);margin-top:2px}.quiz-play-btn{width:38px;height:38px;background:var(--color-primary);color:#fff;border-radius:var(--radius-full);display:flex;align-items:center;justify-content:center;box-shadow:0 4px 12px #4f46e540;transition:transform var(--transition-fast);flex-shrink:0}.quiz-play-btn:active{transform:scale(.9)}.quiz-grid{display:grid;grid-template-columns:1fr 1fr;gap:var(--space-4)}.quiz-grid-card{background:var(--color-surface);border-radius:var(--radius-xl);padding:var(--space-4);display:flex;flex-direction:column;align-items:center;text-align:center;box-shadow:var(--shadow-sm);border:1px solid var(--color-border-light);cursor:pointer;transition:all var(--transition-fast)}.quiz-grid-card:active{transform:scale(.96)}.quiz-grid-card .grid-icon{width:48px;height:48px;border-radius:var(--radius-full);display:flex;align-items:center;justify-content:center;margin-bottom:var(--space-3);font-size:1.3rem}.quiz-grid-card h3{font-size:var(--font-size-sm);font-weight:700;color:var(--color-text)}.quiz-grid-card p{font-size:var(--font-size-xs);color:var(--color-text-muted);text-transform:uppercase;letter-spacing:.1em;font-weight:700;margin-top:4px}.quiz-header{background:var(--color-surface);padding:var(--space-8) var(--space-6) var(--space-4);border-bottom:1px solid var(--color-border-light);position:sticky;top:0;z-index:10}.quiz-header-row{display:flex;align-items:center;gap:var(--space-4)}.quiz-progress-track{flex:1;height:10px;background:var(--color-border);border-radius:var(--radius-full);overflow:hidden}.quiz-progress-fill{height:100%;background:linear-gradient(90deg,var(--color-primary),var(--color-primary-light));border-radius:var(--radius-full);transition:width .5s ease-out}.quiz-timer{display:flex;align-items:center;gap:6px;padding:4px 12px;background:var(--color-accent-bg);border-radius:var(--radius-full);border:1px solid #fde68a;color:#d97706;font-weight:700;font-size:var(--font-size-sm);font-variant-numeric:tabular-nums}.quiz-body{padding:var(--space-8) var(--space-6);padding-bottom:180px}.quiz-tag{display:inline-block;padding:4px 12px;background:var(--color-primary-bg);color:var(--color-primary);font-size:var(--font-size-xs);font-weight:700;border-radius:var(--radius-sm);text-transform:uppercase;letter-spacing:.12em;margin-bottom:var(--space-3)}.quiz-question{font-size:var(--font-size-2xl);font-weight:800;color:var(--color-text);line-height:1.3}.quiz-sentence{margin-top:var(--space-4);padding:var(--space-6);background:var(--color-surface);border:2px solid var(--color-border-light);border-radius:var(--radius-md);font-size:var(--font-size-xl);font-style:italic;color:var(--color-text-secondary);font-weight:500;box-shadow:var(--shadow-sm)}.quiz-options{display:flex;flex-direction:column;gap:var(--space-4);margin-top:var(--space-8)}.quiz-option{display:flex;align-items:center;padding:var(--space-4);border:2px solid var(--color-border);border-radius:var(--radius-md);background:var(--color-surface);cursor:pointer;transition:all .2s ease;-webkit-user-select:none;user-select:none}.quiz-option:active{transform:scale(.98)}.quiz-option:hover{border-color:var(--color-primary-bg)}.quiz-option .option-letter{width:40px;height:40px;border-radius:var(--radius-sm);background:var(--color-bg);color:var(--color-text-muted);font-weight:700;display:flex;align-items:center;justify-content:center;margin-right:var(--space-4);transition:all .2s ease}.quiz-option .option-text{flex:1;font-size:var(--font-size-lg);font-weight:600;color:var(--color-text-secondary)}.quiz-option .option-icon{display:none;margin-left:auto}.quiz-option.selected{border-color:var(--color-primary);background:var(--color-primary-bg)}.quiz-option.selected .option-letter{background:var(--color-primary);color:#fff}.quiz-option.selected .option-text{color:var(--color-primary-dark)}.quiz-option.correct{border-color:var(--color-success);background:var(--color-success-bg)}.quiz-option.correct .option-letter{background:var(--color-success);color:#fff}.quiz-option.correct .option-text{color:#166534;font-weight:700}.quiz-option.correct .option-icon{display:flex;color:var(--color-success)}.quiz-option.incorrect{border-color:var(--color-danger);background:var(--color-danger-bg)}.quiz-option.incorrect .option-letter{background:var(--color-danger);color:#fff}.quiz-option.incorrect .option-text{color:#991b1b;font-weight:700}.quiz-option.incorrect .option-icon{display:flex;color:var(--color-danger)}.quiz-option.disabled{pointer-events:none;opacity:.5}.quiz-feedback{display:none;align-items:center;gap:var(--space-3);padding:var(--space-4);border-radius:var(--radius-md);margin-top:var(--space-4)}.quiz-feedback.show{display:flex}.quiz-feedback.success{background:var(--color-success-bg);border:1px solid #bbf7d0}.quiz-feedback.error{background:var(--color-danger-bg);border:1px solid #fecaca}.quiz-feedback .fb-icon{width:28px;height:28px;border-radius:var(--radius-full);display:flex;align-items:center;justify-content:center;flex-shrink:0}.quiz-feedback.success .fb-icon{background:var(--color-success);color:#fff}.quiz-feedback.error .fb-icon{background:var(--color-danger);color:#fff}.quiz-feedback .fb-title{font-size:var(--font-size-sm);font-weight:700}.quiz-feedback.success .fb-title{color:#166534}.quiz-feedback.error .fb-title{color:#991b1b}.quiz-feedback .fb-text{font-size:var(--font-size-xs);margin-top:2px}.quiz-feedback.success .fb-text{color:#15803d}.quiz-feedback.error .fb-text{color:#b91c1c}.hint-btn{display:flex;align-items:center;justify-content:center;gap:var(--space-2);padding:10px 24px;background:var(--color-primary-bg);color:var(--color-primary);font-weight:700;font-size:var(--font-size-sm);border-radius:var(--radius-full);border:1px solid #c7d2fe;margin:var(--space-8) auto 0;transition:all var(--transition-fast)}.hint-btn:hover{background:#ddd6fe}.quiz-footer{position:fixed;bottom:0;left:0;right:0;background:var(--color-surface);border-top:1px solid var(--color-border-light);padding:var(--space-6);box-shadow:0 -4px 20px #00000008;z-index:20}.quiz-footer .inner{max-width:480px;margin:0 auto}.vocab-input-wrapper{display:flex;align-items:center;gap:var(--space-2);margin-top:var(--space-6);flex-wrap:wrap}.vocab-letter-box{width:40px;height:48px;background:var(--color-surface);border:2px solid 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ease-out}.stat-bar-label{font-size:var(--font-size-xs);color:var(--color-text-muted)}.stat-bar-label.active{color:var(--color-text-secondary);font-weight:600}.stat-summary{display:flex;justify-content:space-between;margin-top:var(--space-4);padding-top:var(--space-4);border-top:1px solid var(--color-border-light)}.stat-summary .label{font-size:var(--font-size-xs);color:var(--color-text-muted);text-transform:uppercase;letter-spacing:.1em}.stat-summary .value{font-size:var(--font-size-xl);font-weight:800}.stat-summary .trend{font-size:var(--font-size-xs);font-weight:600;color:var(--color-secondary)}.word-review-card{background:var(--color-surface);padding:var(--space-4);border-radius:var(--radius-md);display:flex;align-items:flex-start;gap:var(--space-4);border:1px solid 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var(--color-border-light);padding:var(--space-3) var(--space-8) calc(var(--space-3) + env(safe-area-inset-bottom,0px));display:flex;justify-content:space-between;align-items:center;border-radius:var(--radius-xl) var(--radius-xl) 0 0;box-shadow:0 -4px 20px #00000008}.nav-item{display:flex;flex-direction:column;align-items:center;gap:3px;color:var(--color-text-muted);transition:color var(--transition-fast);padding:var(--space-1) var(--space-3)}.nav-item.active{color:var(--color-primary)}.nav-item .nav-icon{width:24px;height:24px}.nav-item .nav-label{font-size:8px;font-weight:700;text-transform:uppercase;letter-spacing:.15em}.space-y>*+*{margin-top:var(--space-6)}.space-y-sm>*+*{margin-top:var(--space-4)}.space-y-lg>*+*{margin-top:var(--space-8)}.mt-4{margin-top:var(--space-4)}.mt-6{margin-top:var(--space-6)}.mt-8{margin-top:var(--space-8)}.mb-4{margin-bottom:var(--space-4)}.text-center{text-align:center}@keyframes fadeIn{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}@keyframes slideUp{0%{opacity:0;transform:translateY(24px)}to{opacity:1;transform:translateY(0)}}@keyframes scaleIn{0%{opacity:0;transform:scale(.92)}to{opacity:1;transform:scale(1)}}@keyframes shake{0%,to{transform:translate(0)}25%{transform:translate(-5px)}75%{transform:translate(5px)}}.animate-fade-in{animation:fadeIn .4s ease-out both}.animate-slide-up{animation:slideUp .5s ease-out both}.animate-scale-in{animation:scaleIn .3s ease-out both}.animate-shake{animation:shake .4s ease-in-out}.stagger>*:nth-child(1){animation-delay:0ms}.stagger>*:nth-child(2){animation-delay:60ms}.stagger>*:nth-child(3){animation-delay:.12s}.stagger>*:nth-child(4){animation-delay:.18s}.stagger>*:nth-child(5){animation-delay:.24s}.stagger>*:nth-child(6){animation-delay:.3s}.quiz-complete{display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;padding:var(--space-8);min-height:60vh}.quiz-complete .emoji{font-size:4rem;margin-bottom:var(--space-4)}.quiz-complete h2{font-size:var(--font-size-2xl);font-weight:900;color:var(--color-text);margin-bottom:var(--space-2)}.quiz-complete .score-text{font-size:var(--font-size-3xl);font-weight:900;color:var(--color-primary);margin:var(--space-4) 0}.quiz-complete .message{font-size:var(--font-size-base);color:var(--color-text-secondary);margin-bottom:var(--space-8)}.skeleton{background:linear-gradient(110deg,var(--color-bg) 8%,#e2e8f0 18%,var(--color-bg) 33%);background-size:200% 100%;animation:shimmer 1.5s linear infinite;border-radius:var(--radius-sm)}@keyframes shimmer{0%{background-position:200% 0}to{background-position:-200% 0}}.no-scroll{overflow:hidden}.btn-speak{display:inline-flex;align-items:center;justify-content:center;width:28px;height:28px;border-radius:var(--radius-full);background:var(--color-primary-bg);color:var(--color-primary);font-size:.875rem;cursor:pointer;transition:all var(--transition-fast);vertical-align:middle;margin-left:4px;border:none}.btn-speak:hover{background:var(--color-primary);color:#fff}.theme-toggle{width:36px;height:36px;display:flex;align-items:center;justify-content:center;background:var(--color-bg);border-radius:var(--radius-full);color:var(--color-text-secondary);cursor:pointer;transition:all var(--transition-fast);font-size:1.1rem;border:none}.theme-toggle:hover{background:var(--color-border)}[data-theme=dark]{--color-primary-bg: #312e81;--color-secondary-bg: #064e3b;--color-accent-bg: #451a03;--color-danger-bg: #450a0a;--color-success-bg: #052e16;--color-bg: #0f172a;--color-surface: #1e293b;--color-text: #f1f5f9;--color-text-secondary: #94a3b8;--color-text-muted: #64748b;--color-border: #334155;--color-border-light: #1e293b;--color-dark: #0f172a;--shadow-sm: 0 1px 3px rgba(0, 0, 0, .3);--shadow-md: 0 4px 20px -2px rgba(0, 0, 0, .4);--shadow-lg: 0 10px 40px -4px rgba(0, 0, 0, .5)}[data-theme=dark] .quiz-option.correct .option-text{color:#4ade80}[data-theme=dark] .quiz-option.incorrect .option-text{color:#fca5a5}[data-theme=dark] .btn-white{background:var(--color-surface);color:var(--color-primary-light)}[data-theme=dark] .search-bar input{background:var(--color-surface);color:var(--color-text)}[data-theme=dark] .search-bar input:focus{background:#334155}[data-theme=dark] .vocab-input{background:var(--color-surface);color:var(--color-text)}[data-theme=dark] .vocab-letter-box{background:var(--color-surface);border-color:var(--color-border);color:var(--color-text)}[data-theme=dark] .vocab-letter-box.hint{background:var(--color-primary-bg);border-color:var(--color-primary)}.flashcard-page{padding:var(--space-6);display:flex;flex-direction:column;align-items:center;gap:var(--space-8);padding-top:var(--space-8)}.fc-card{width:100%;max-width:360px;height:320px;perspective:1000px;cursor:pointer;position:relative}.fc-card .fc-front,.fc-card .fc-back{position:absolute;width:100%;height:100%;backface-visibility:hidden;border-radius:var(--radius-xl);display:flex;flex-direction:column;align-items:center;justify-content:center;padding:var(--space-8);transition:transform .5s cubic-bezier(.4,0,.2,1);box-shadow:var(--shadow-lg);text-align:center}.fc-card .fc-front{background:linear-gradient(135deg,var(--color-primary),var(--color-primary-light));color:#fff}.fc-card .fc-back{background:var(--color-surface);color:var(--color-text);border:2px solid var(--color-border-light);transform:rotateY(180deg)}.fc-card.flipped .fc-front{transform:rotateY(180deg)}.fc-card.flipped .fc-back{transform:rotateY(0)}.fc-label{font-size:var(--font-size-xs);font-weight:700;letter-spacing:.15em;opacity:.7;margin-bottom:var(--space-4)}.fc-word{font-size:2.5rem;font-weight:900;margin-bottom:var(--space-2)}.fc-phonetic{font-size:var(--font-size-base);opacity:.7;font-style:italic;margin-bottom:var(--space-4)}.fc-speak-btn{width:44px;height:44px;border-radius:var(--radius-full);background:#fff3;display:flex;align-items:center;justify-content:center;color:#fff;border:none;cursor:pointer;transition:background var(--transition-fast)}.fc-speak-btn:hover{background:#ffffff59}.fc-definition{font-size:var(--font-size-lg);font-weight:600;color:var(--color-text);line-height:1.5;margin-bottom:var(--space-4)}.fc-sentence{font-size:var(--font-size-sm);color:var(--color-text-muted);font-style:italic;line-height:1.6}.fc-actions{display:flex;gap:var(--space-3);width:100%;max-width:360px}.fc-action-btn{flex:1;display:flex;flex-direction:column;align-items:center;gap:var(--space-1);padding:var(--space-3);border-radius:var(--radius-md);font-size:var(--font-size-xs);font-weight:700;border:2px solid var(--color-border);background:var(--color-surface);color:var(--color-text-muted);cursor:pointer;transition:all var(--transition-fast)}.fc-action-btn:active{transform:scale(.95)}.fc-again{border-color:var(--color-danger);color:var(--color-danger)}.fc-again:hover{background:var(--color-danger-bg)}.fc-good{border-color:var(--color-success);color:var(--color-success)}.fc-good:hover{background:var(--color-success-bg)}.fc-master{border-color:var(--color-accent);color:var(--color-accent)}.fc-master:hover{background:var(--color-accent-bg)}.fc-master.active{background:var(--color-accent);color:#fff}.level-chip{padding:4px 14px;border-radius:var(--radius-full);font-size:var(--font-size-xs);font-weight:700;border:2px solid var(--color-border);background:transparent;color:var(--color-text-muted);cursor:pointer;transition:all var(--transition-fast)}.level-chip:hover{border-color:var(--color-primary-light)}.level-chip.active{background:var(--color-primary);border-color:var(--color-primary);color:#fff}.grammar-card{background:var(--color-card);border:1px solid var(--color-border);border-radius:var(--radius-lg);padding:var(--space-6);box-shadow:var(--shadow-card)}.grammar-sentence{font-size:var(--font-size-base);line-height:2.2;color:var(--color-text)}.grammar-sentence u{text-decoration-color:var(--color-primary);text-underline-offset:3px;font-weight:600;cursor:default;transition:all var(--transition-fast)}.grammar-answer-section{margin-top:var(--space-6)}.grammar-inputs{display:flex;align-items:flex-end;gap:var(--space-3)}.grammar-input-group{display:flex;flex-direction:column;gap:4px}.grammar-label{font-size:var(--font-size-xs);font-weight:700;color:var(--color-text-muted);text-transform:uppercase;letter-spacing:.5px}.grammar-letter-input{width:52px;height:48px;border:2px solid var(--color-border);border-radius:var(--radius-md);background:var(--color-card);color:var(--color-text);font-size:1.25rem;font-weight:800;text-align:center;text-transform:uppercase;outline:none;transition:border-color var(--transition-fast)}.grammar-letter-input:focus{border-color:var(--color-primary);box-shadow:0 0 0 3px var(--color-primary-bg)}.grammar-correction-input{height:48px;width:100%;border:2px solid var(--color-border);border-radius:var(--radius-md);background:var(--color-card);color:var(--color-text);font-size:1rem;font-weight:600;padding:0 var(--space-4);outline:none;transition:border-color var(--transition-fast)}.grammar-correction-input:focus{border-color:var(--color-primary);box-shadow:0 0 0 3px var(--color-primary-bg)}.grammar-dash{font-size:1.25rem;color:var(--color-text-muted);font-weight:700;padding-bottom:12px}