:root{--primary:#2563eb;--primary-hover:#1d4ed8;--primary-light:#eff6ff;--primary-border:#bfdbfe;--bg-main:#f8fafc;--bg-card:#fff;--bg-muted:#f1f5f9;--bg-surface:#fff;--text-main:#0f172a;--text-muted:#475569;--text-dim:#94a3b8;--border-subtle:#e2e8f0;--border-strong:#cbd5e1;--border-card:#e2e8f0;--status-correct:#16a34a;--status-correct-bg:#f0fdf4;--status-correct-border:#bbf7d0;--status-correct-text:#15803d;--status-acceptable:#2563eb;--status-acceptable-bg:#eff6ff;--status-acceptable-border:#bfdbfe;--status-acceptable-text:#1d4ed8;--status-incorrect:#dc2626;--status-incorrect-bg:#fef2f2;--status-incorrect-border:#fecaca;--status-incorrect-text:#b91c1c;--radius-sm:6px;--radius-md:10px;--radius-lg:14px;--radius-xl:18px;--shadow-sm:0 1px 2px #0000000d;--shadow-md:0 4px 6px -1px #00000012, 0 2px 4px -1px #0000000a;--shadow-lg:0 10px 15px -3px #00000014, 0 4px 6px -2px 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140px;width:140px;min-width:140px;max-width:140px}.filter-bar-search{flex:1;min-width:200px;position:relative}.filter-bar-checkbox-group{align-items:center;display:flex}.filter-bar-btn{flex-shrink:0;justify-content:center;align-items:center;width:140px;height:42px;padding:0 16px;font-size:.9rem;font-weight:700;display:inline-flex}.practice-actions-row{justify-content:space-between;align-items:center;gap:10px;margin-top:14px;display:flex}.practice-action-btn{justify-content:center;align-items:center;gap:6px;height:42px;padding:0 20px;font-size:.9rem;font-weight:700;display:inline-flex}.form-input,.form-textarea{border:1px solid var(--border-strong);border-radius:var(--radius-md);width:100%;color:var(--text-main);background:#fff;outline:none;padding:10px 14px;font-family:inherit;font-size:.95rem;transition:all .2s}.form-input:focus,.form-textarea:focus{border-color:var(--primary);box-shadow:0 0 0 3px 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#0000;border-bottom-color:#fefce8;position:absolute;top:auto;bottom:100%;right:18px}.grammar-tooltip-box.bottom-positioned.left-aligned:after{left:18px;right:auto}.grammar-tooltip-box.bottom-positioned.center-aligned:after{left:50%;right:auto;transform:translate(-50%)}.badge-correct{background:var(--status-correct-bg);color:var(--status-correct-text);border:1px solid var(--status-correct-border)}.badge-acceptable{background:var(--status-acceptable-bg);color:var(--status-acceptable-text);border:1px solid var(--status-acceptable-border)}.badge-incorrect{background:var(--status-incorrect-bg);color:var(--status-incorrect-text);border:1px solid var(--status-incorrect-border)}.cards-grid{grid-template-columns:repeat(auto-fill,minmax(320px,1fr));gap:16px;display:grid}.comparison-grid{grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:12px;display:grid}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}.animate-spin{animation:1s linear infinite spin}@keyframes 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(width<=1024px){.cards-grid{grid-template-columns:repeat(2,1fr);gap:14px}}@media (width<=768px){.header-inner{flex-direction:column;align-items:stretch;gap:12px}.header-nav{justify-content:space-between;width:100%}.nav-tab-button{flex:1;padding:8px 6px;font-size:.82rem}.app-header{margin:14px auto 16px}.app-container{padding:0 12px 32px}}@media (width<=640px){.cards-grid{grid-template-columns:1fr;gap:12px}.filter-bar-container{gap:8px}.filter-bar-select,.category-select-box{flex:0 0 140px!important;order:1!important;width:140px!important;min-width:140px!important;max-width:140px!important}.filter-bar-checkbox,.filter-bar-checkbox-group{flex-shrink:0;align-items:center;height:42px;display:flex;order:2!important}.filter-bar-btn{white-space:nowrap;flex:auto!important;order:3!important;width:auto!important;min-width:0!important;padding:0 14px!important}.filter-bar-search{order:4!important;width:100%!important;min-width:100%!important}.wrong-filter-bar-container{flex-wrap:wrap!important;align-items:center!important;gap:6px!important;display:flex!important}.wrong-filter-bar-container .filter-bar-select{flex:0 0 140px!important;order:1!important;width:140px!important;min-width:140px!important;max-width:140px!important}.wrong-filter-bar-container .filter-bar-checkbox{flex:none!important;order:2!important;padding:0 2px!important}.wrong-filter-bar-container .filter-bar-checkbox label{gap:3px!important;padding:0 2px!important;font-size:.76rem!important}.wrong-filter-bar-container .filter-bar-btn{flex:auto!important;order:3!important;min-width:0!important;padding:0 8px!important;font-size:.8rem!important}.wrong-filter-bar-container .filter-bar-search{order:4!important;width:100%!important;min-width:100%!important;margin-top:4px!important}.practice-filter-bar-row{flex-wrap:nowrap!important;align-items:center!important;gap:6px!important;width:100%!important;display:flex!important}.practice-filter-bar-row .practice-select-box{flex:0 0 140px!important;order:1!important;width:140px!important;min-width:140px!important;max-width:140px!important}.practice-filter-bar-row .practice-select-box select{padding:4px 6px!important;font-size:.8rem!important}.practice-filter-bar-row .practice-scope-label{white-space:nowrap!important;flex-shrink:0!important;order:2!important;font-size:.74rem!important}.practice-filter-bar-row .practice-progress-wrapper{flex:auto!important;order:3!important;align-items:center!important;gap:4px!important;min-width:0!important;margin-left:auto!important;display:inline-flex!important}.practice-filter-bar-row 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