:root{font-family:system-ui,Avenir,Helvetica,Arial,sans-serif;line-height:1.5;font-weight:400;color-scheme:light dark;color:#ffffffde;background-color:#242424;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}a{font-weight:500;color:#646cff;text-decoration:inherit}a:hover{color:#535bf2}body{margin:0;display:flex;place-items:center;min-width:320px;min-height:100vh}h1{font-size:3.2em;line-height:1.1}button{border-radius:8px;border:1px solid transparent;padding:.6em 1.2em;font-size:1em;font-weight:500;font-family:inherit;background-color:#1a1a1a;cursor:pointer;transition:border-color .25s}button:hover{border-color:#646cff}button:focus,button:focus-visible{outline:4px auto -webkit-focus-ring-color}@media(prefers-color-scheme:light){:root{color:#213547;background-color:#fff}a:hover{color:#747bff}button{background-color:#f9f9f9}}:root{--bg-color: #f3f4f6;--text-main: #111827;--text-muted: #6b7280;--card-bg: #ffffff;--primary-color: #4b8ae6;--primary-hover: #3a75c4;--wrong-color: #e07a7a;--wrong-hover: #c96b6b;--right-color: #7bba91;--right-hover: #67a37d;--border-color: #e5e7eb}[data-theme=dark]{--bg-color: #111827;--text-main: #f9fafb;--text-muted: #9ca3af;--card-bg: #1f2937;--primary-color: #5c9cf2;--primary-hover: #7eb3f7;--wrong-color: #cc6c6c;--wrong-hover: #e08b8b;--right-color: #6da381;--right-hover: #8fc7a4;--border-color: #374151}body{margin:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif;background-color:var(--bg-color);color:var(--text-main);display:flex;justify-content:center;align-items:flex-start;min-height:100vh;min-height:-webkit-fill-available;transition:background-color .3s ease,color .3s ease;overflow-x:hidden}html{height:-webkit-fill-available}.app{width:100%;max-width:500px;margin:0 auto;padding:16px;box-sizing:border-box;display:flex;flex-direction:column;min-height:100vh}.header-actions{display:flex;justify-content:flex-end;gap:8px;padding:10px 0;margin-bottom:10px}.icon-btn{background:var(--card-bg);border:1px solid var(--border-color);color:var(--text-muted);cursor:pointer;width:44px;height:44px;border-radius:50%;display:flex;align-items:center;justify-content:center;transition:all .2s;-webkit-appearance:none;appearance:none;box-shadow:0 2px 5px #0000000d;padding:0;overflow:hidden}.icon-btn svg{display:block;width:20px;height:20px;stroke:currentColor;stroke-width:2;flex-shrink:0}.icon-btn:hover{background-color:var(--border-color);color:var(--text-main);border-color:var(--primary-color)}.app-header{text-align:center;margin-bottom:30px}.app-header h1{margin:0;font-size:2.5rem;font-weight:800;letter-spacing:-.05em;color:var(--text-main);display:flex;align-items:center;justify-content:center;gap:12px}.card-panel{background:var(--card-bg);padding:24px;border-radius:24px;box-shadow:0 10px 30px -5px #00000014;border:1px solid var(--border-color);width:100%;box-sizing:border-box;margin-bottom:20px}.card-panel h2{margin-top:0;margin-bottom:24px;font-size:1.5rem;font-weight:700}.category-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(140px,1fr));gap:12px;max-height:400px;overflow-y:auto;padding:4px;margin-bottom:24px;border-radius:12px}.category-grid::-webkit-scrollbar{width:6px}.category-grid::-webkit-scrollbar-track{background:transparent}.category-grid::-webkit-scrollbar-thumb{background:var(--border-color);border-radius:10px}.category-item{background:var(--bg-color);border:2px solid var(--border-color);border-radius:12px;padding:16px;text-align:center;cursor:pointer;font-weight:700;font-size:.9rem;transition:all .2s;display:flex;align-items:center;justify-content:center;min-height:60px;color:var(--text-main);-webkit-user-select:none;user-select:none}.category-item:hover{border-color:var(--primary-color);transform:translateY(-2px)}.category-item.active{background:var(--primary-color);border-color:var(--primary-color);color:#fff;box-shadow:0 4px 12px #4b8ae64d}.form-group{margin-bottom:20px}.form-group label{display:block;font-size:.85rem;font-weight:700;color:var(--text-muted);text-transform:uppercase;margin-bottom:8px;letter-spacing:.05em}.input-field,select{width:100%;padding:14px 16px;font-size:16px;background-color:var(--bg-color);color:var(--text-main);border:1px solid var(--border-color);border-radius:12px;box-sizing:border-box;outline:none;-webkit-appearance:none}select{background-image:url(data:image/svg+xml;charset=UTF-8,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20width%3D%2224%22%20height%3D%2224%22%20viewBox%3D%220%200%2024%2024%22%20fill%3D%22none%22%20stroke%3D%22currentColor%22%20stroke-width%3D%222%22%20stroke-linecap%3D%22round%22%20stroke-linejoin%3D%22round%22%3E%3Cpolyline%20points%3D%226%209%2012%2015%2018%209%22%3E%3C%2Fpolyline%3E%3C%2Fsvg%3E);background-repeat:no-repeat;background-position:right 12px center;background-size:16px;padding-right:40px}.btn-primary{width:100%;padding:16px;background-color:var(--primary-color);color:#fff;border:none;border-radius:12px;font-size:1rem;font-weight:700;cursor:pointer;-webkit-appearance:none;transition:opacity .2s}.btn-primary:active{opacity:.8}.session-header{display:flex;justify-content:space-between;align-items:center;width:100%;margin-bottom:20px;padding:0 4px}.session-header span{font-weight:700;color:var(--text-muted);font-size:.9rem}.btn-cancel{grid-column:3;justify-self:end;background:#0000000d;border:none;color:var(--text-muted);cursor:pointer;font-size:.8rem;font-weight:700;padding:8px 16px;border-radius:20px;-webkit-appearance:none}[data-theme=dark] .btn-cancel{background:#ffffff1a}.flashcard-container{width:100%;display:flex;flex-direction:column;gap:20px}.flashcard{width:100%;height:300px;perspective:1000px}.flashcard-inner{position:relative;width:100%;height:100%;transition:transform .6s cubic-bezier(.4,0,.2,1);transform-style:preserve-3d;border-radius:24px;box-shadow:0 8px 25px #0000001a}.flashcard.flipped .flashcard-inner{transform:rotateY(180deg)}.flashcard-front,.flashcard-back{position:absolute;inset:0;-webkit-backface-visibility:hidden;backface-visibility:hidden;display:flex;flex-direction:column;align-items:center;justify-content:center;border-radius:24px;background-color:var(--card-bg);padding:24px;border:1px solid var(--border-color)}.flashcard-back{transform:rotateY(180deg)}.flashcard h2{font-size:1.8rem;font-weight:800;margin:0;text-align:center;word-break:break-word}.media-controls{display:flex;gap:20px;margin-top:24px;justify-content:center}.mic-btn,.audio-btn{width:56px;height:56px;border-radius:50%;border:none;background:var(--bg-color);color:var(--primary-color);display:flex;align-items:center;justify-content:center;cursor:pointer;-webkit-appearance:none;transition:all .2s}.mic-btn.listening{color:#ef4444;animation:pulse-red 1.5s infinite}.action-buttons{display:flex;gap:12px;margin-top:10px}.action-buttons button{flex:1;padding:18px;border-radius:16px;font-size:1rem;font-weight:800;cursor:pointer;background:var(--card-bg);-webkit-appearance:none;border:2px solid transparent}.btn-wrong{border-color:var(--wrong-color)!important;color:var(--wrong-color)}.btn-right{border-color:var(--right-color)!important;color:var(--right-color)}@keyframes pulse-red{0%{box-shadow:0 0 #ef444466}70%{box-shadow:0 0 0 12px #ef444400}to{box-shadow:0 0 #ef444400}}@keyframes shake{0%,to{transform:translate(0)}20%,60%{transform:translate(-6px)}40%,80%{transform:translate(6px)}}.shake{animation:shake .4s ease-in-out}@media(max-width:480px){.app{padding:12px}.app-header h1{font-size:2.2rem}.card-panel{padding:20px}.flashcard{height:260px}.flashcard h2{font-size:1.6rem}}.speech-result{height:20px;margin-top:12px;font-size:.85rem;font-weight:700;opacity:0;transition:opacity .2s;text-align:center}.speech-result.show-feedback{opacity:1}.success-text{color:var(--right-color)}.error-text{color:var(--wrong-color)}.btn-hidden{visibility:hidden;opacity:0}.app-footer{text-align:center;padding:10px;font-size:.8rem;color:var(--text-color, #666);opacity:.7}