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p{color:#cbd5e1;font-size:1.1rem;max-width:600px}.study-panel{display:grid;gap:1.25rem;padding:2rem}.panel-title-row{display:flex;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:.5rem;min-width:0;margin-bottom:.5rem}.panel-title-row h2{font-size:1.5rem;margin:0}.panel-title-row small{color:var(--ink-secondary);font-size:.85rem;font-weight:500;background:var(--bg-base);padding:.25rem .75rem;border-radius:999px;border:1px solid var(--border-light)}.card{perspective:1000px;border:1px solid var(--border-strong);border-radius:var(--radius-xl);background:var(--bg-surface);min-height:320px;padding:1.5rem;box-shadow:var(--shadow-lg);position:relative;transition:transform .3s ease}.card-empty{opacity:.6;border-style:dashed;box-shadow:none}.card-side{display:grid;gap:1.25rem;align-content:start;animation:fadeIn .4s cubic-bezier(.16,1,.3,1) forwards}@keyframes fadeIn{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}#cardFront,#cardBack{background:var(--bg-surface-raised);border:1px solid var(--border-light);border-radius:var(--radius-lg);padding:1.5rem}#cardBack{background:#fefce8;border-color:#fef08a}.badge{width:max-content;font-size:.75rem;font-weight:600;letter-spacing:.05em;text-transform:uppercase;padding:.35rem .75rem;border-radius:999px;background:var(--accent-soft);color:var(--accent-ink);border:1px solid rgba(37,99,235,.2)}.badge-back{background:#fef9c3;color:#854d0e;border-color:#eab3084d}.instruction{color:var(--ink-secondary);font-size:.95rem;font-weight:500}.content{font-family:"DM Serif Display",serif;font-size:clamp(1.75rem,4vw,2.5rem);line-height:1.3;color:var(--ink-primary)}.subcontent{color:var(--ink-secondary);font-size:1.1rem;line-height:1.6}.grammar-tip{font-size:.95rem;color:var(--ink-secondary);background:var(--bg-surface);border:1px solid var(--border-light);border-radius:var(--radius-md);padding:1rem;line-height:1.6;border-left:4px solid var(--accent)}.card-insights{padding:1rem}.card-insights-details{border:1px solid var(--border-light);border-radius:var(--radius-lg);background:var(--bg-surface-raised)}.card-insights-details summary{list-style:none;cursor:pointer;font-weight:700;color:var(--ink-primary);padding:.85rem 1rem;-webkit-user-select:none;user-select:none}.card-insights-details summary::-webkit-details-marker{display:none}.card-insights-details summary:after{content:"Mostrar";float:right;font-size:.8rem;color:var(--ink-secondary);font-weight:600}.card-insights-details[open] summary{border-bottom:1px solid var(--border-light)}.card-insights-details[open] summary:after{content:"Ocultar"}.card-insights-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:.9rem}.insight-card{border:1px solid var(--border-light);border-radius:var(--radius-md);padding:.9rem;background:var(--bg-surface)}.insight-card h3{font-size:1.05rem;margin-bottom:.55rem}.insight-list{list-style:none;display:grid;gap:.35rem}.insight-list li{display:flex;justify-content:space-between;gap:.75rem;font-size:.86rem;border-bottom:1px dashed var(--border-light);padding-bottom:.3rem}.insight-list li:last-child{border-bottom:0;padding-bottom:0}.insight-list span{color:var(--ink-secondary)}.insight-list strong{color:var(--ink-primary);text-align:right;max-width:56%}.study-actions,.rating-row{display:flex;flex-wrap:wrap;gap:.75rem;margin-top:.5rem}.btn{font-family:inherit;font-weight:600;font-size:.95rem;border:1px solid transparent;border-radius:var(--radius-md);padding:.75rem 1.25rem;cursor:pointer;transition:all .2s cubic-bezier(.4,0,.2,1);display:inline-flex;align-items:center;justify-content:center;gap:.5rem}.btn:active{transform:scale(.97)}.btn:disabled{opacity:.6;cursor:not-allowed;transform:none}.btn-primary{background:var(--accent);color:#fff;box-shadow:0 1px 2px #0000000d,inset 0 1px 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var(--border-strong);padding-top:1.25rem;margin-top:.5rem}.qa-row{display:flex;gap:.5rem}input,select{font-family:inherit;font-size:.95rem;width:100%;border:1px solid var(--border-strong);border-radius:var(--radius-md);padding:.75rem 1rem;background:var(--bg-surface);color:var(--ink-primary);transition:border-color .2s,box-shadow .2s;box-shadow:inset 0 1px 2px #00000005}input:focus,select:focus{outline:none;border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-soft)}.qa-input{flex:1;min-width:0}.qa-answer{font-size:.95rem;line-height:1.6;color:var(--ink-primary);background:var(--bg-base);border:1px solid var(--border-light);border-radius:var(--radius-md);padding:1rem;white-space:pre-wrap;max-height:280px;overflow:auto}.stats-panel{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:1rem;padding:1.5rem}.stat{background:var(--bg-surface-raised);border:1px solid 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var(--border-light);border-radius:var(--radius-md);padding:1rem}.settings-docs summary{font-weight:600;cursor:pointer;outline:none}.docs-list{margin-top:1rem;display:grid;gap:.5rem;font-size:.9rem;color:var(--ink-secondary)}@media(max-width:768px){.app-shell{padding:1.5rem 1rem}.stats-panel{grid-template-columns:1fr}.study-panel{padding:1.25rem}.qa-row{flex-direction:column}.btn-rating{flex:1 1 calc(50% - .5rem)}.card-insights-grid{grid-template-columns:1fr}}.word-tooltip-list{list-style:none;display:grid;gap:.5rem;margin:0;padding:0}.word-tooltip-item{display:grid;gap:.25rem;background:#ffffff0d;border:1px solid rgba(255,255,255,.1);border-radius:var(--radius-sm);padding:.5rem .75rem}.word-tooltip-meta{width:fit-content;font-size:.65rem;font-weight:700;letter-spacing:.05em;text-transform:uppercase;color:#93c5fd;background:#2563eb33;border-radius:999px;padding:.15rem .5rem}.word-tooltip-fr{color:#f8fafc;font-weight:500}.word-tooltip-pt{color:#cbd5e1;font-size:.9rem}#voiceModeBtn{transition:all .3s ease}#voiceModeBtn.voice-active{background:var(--danger-soft);color:var(--danger);border-color:#e11d4866;animation:pulse-border 2s infinite}@keyframes pulse-border{0%{box-shadow:0 0 #e11d4866}70%{box-shadow:0 0 0 8px #e11d4800}to{box-shadow:0 0 #e11d4800}}