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.3s ease;display:flex;align-items:center;justify-content:center;font-size:9px;font-weight:700;color:#fff;text-shadow:0 1px 1px rgba(0,0,0,.2)}.learning-section::-webkit-scrollbar{width:3px}.learning-section::-webkit-scrollbar-track{background:transparent}.learning-section::-webkit-scrollbar-thumb{background:#ccc;border-radius:2px}.learning-section::-webkit-scrollbar-thumb:hover{background:#999}.ai-hint-controls{display:flex;flex-direction:column;gap:6px;margin-top:6px;padding-top:6px;border-top:1px solid #e5e7eb;flex-shrink:0}.ai-hint-button{display:flex;align-items:center;justify-content:center;gap:6px;padding:8px 10px;background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;border:none;border-radius:4px;font-size:11px;font-weight:600;cursor:pointer;transition:all .3s ease;box-shadow:0 2px 6px #667eea4d;white-space:normal;word-break:break-word;flex-shrink:0}.ai-hint-button:hover:not(:disabled){transform:translateY(-1px);box-shadow:0 3px 8px #667eea66;background:linear-gradient(135deg,#764ba2,#667eea)}.ai-hint-button:active:not(:disabled){transform:translateY(0)}.ai-hint-button:disabled{opacity:.6;cursor:not-allowed;box-shadow:none}.ai-hint-button svg{width:14px;height:14px;flex-shrink:0}.ai-hint-button.loading svg{animation:spin 1s linear infinite}.hint-constraint-info{font-size:10px;color:#888;text-align:center;display:block;flex-shrink:0;word-break:break-word;width:100%}.hint-constraint-message{display:flex;align-items:center;padding:6px 8px;background-color:#d4edda;color:#155724;border:1px solid #c3e6cb;border-radius:3px;font-size:10px;margin-top:4px;text-align:center;justify-content:center;flex-shrink:0;word-break:break-word}@media(max-width:1400px){.learning-panel{width:32%;min-width:280px;max-width:380px}}@media(max-width:1200px){.learning-panel{width:35%;min-width:250px;max-width:350px}.learning-section{padding:5px 6px}.section-title{font-size:10px;margin-bottom:3px}.feedback-item{padding:3px 5px;font-size:10px}.hint-box{font-size:10px;padding:5px}}@media(max-width:768px){.learning-panel{width:100%;min-width:auto;max-width:100%}.learning-section{border-bottom:1px solid #e0e0e0}.learning-section:last-child{border-bottom:none}.progress-bar{height:16px}}.detail-feedback-button{display:inline-flex;align-items:center;gap:6px;margin-top:10px;padding:7px 14px;font-size:13px;font-weight:600;color:#4f46e5;background:#eef2ff;border:1.5px solid #c7d2fe;border-radius:6px;cursor:pointer;transition:background .15s,border-color .15s,color .15s}.detail-feedback-button:hover:not(:disabled){background:#e0e7ff;border-color:#818cf8;color:#3730a3}.detail-feedback-button:disabled,.detail-feedback-button.loading{opacity:.65;cursor:not-allowed}.detail-feedback-overlay{position:fixed;inset:0;background:#00000073;-webkit-backdrop-filter:blur(3px);backdrop-filter:blur(3px);z-index:9999;display:flex;align-items:center;justify-content:center;padding:20px;animation:dfOverlayIn .18s ease}@keyframes dfOverlayIn{0%{opacity:0}to{opacity:1}}.detail-feedback-modal{background:#fff;border-radius:12px;box-shadow:0 20px 60px #0003,0 4px 16px #0000001a;width:100%;max-width:580px;max-height:80vh;display:flex;flex-direction:column;overflow:hidden;animation:dfModalUp .2s ease}@keyframes dfModalUp{0%{transform:translateY(16px);opacity:0}to{transform:translateY(0);opacity:1}}.detail-feedback-modal-header{display:flex;align-items:center;justify-content:space-between;padding:16px 20px;border-bottom:1px solid #e5e7eb;font-size:15px;font-weight:700;color:#111827;background:#fafafa;flex-shrink:0}.detail-feedback-close{display:flex;align-items:center;justify-content:center;width:30px;height:30px;border:none;background:transparent;border-radius:6px;cursor:pointer;color:#6b7280;transition:background .12s,color .12s}.detail-feedback-close:hover{background:#f3f4f6;color:#111827}.detail-feedback-modal-body{flex:1;overflow-y:auto;padding:20px}.detail-feedback-loading{display:flex;flex-direction:column;align-items:center;gap:14px;padding:40px 20px;color:#6b7280;font-size:14px;text-align:center}.detail-feedback-error{display:flex;flex-direction:column;align-items:center;gap:12px;padding:30px 20px;color:#b91c1c;font-size:14px;text-align:center}.detail-feedback-retry{padding:7px 18px;font-size:13px;font-weight:600;background:#fee2e2;color:#b91c1c;border:1.5px solid #fca5a5;border-radius:6px;cursor:pointer;transition:background .12s}.detail-feedback-retry:hover{background:#fecaca}.detail-feedback-content{font-size:14px;line-height:1.7;color:#374151}.detail-feedback-modal-footer{display:flex;align-items:center;justify-content:flex-end;gap:10px;padding:12px 20px;border-top:1px solid #e5e7eb;background:#fafafa;flex-shrink:0}.detail-feedback-refresh{display:inline-flex;align-items:center;gap:5px;padding:7px 14px;font-size:13px;font-weight:500;background:transparent;color:#6b7280;border:1.5px solid #d1d5db;border-radius:6px;cursor:pointer;transition:background .12s,color .12s}.detail-feedback-refresh:hover{background:#f3f4f6;color:#374151}.detail-feedback-done{padding:7px 20px;font-size:13px;font-weight:600;background:#4f46e5;color:#fff;border:none;border-radius:6px;cursor:pointer;transition:background .15s}.detail-feedback-done:hover{background:#4338ca}@keyframes spin{0%{transform:rotate(0)}to{transform:rotate(360deg)}}