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var(--separator);background:var(--card)}.hint-fold{background:var(--bg);border-radius:var(--radius-sm);padding:14px;text-align:center;margin-bottom:10px;display:flex;flex-direction:column;align-items:center;gap:10px}.hint-fold p{font-size:13px;color:var(--text2);line-height:1.4}.hint-show{padding:12px 14px;background:var(--success-light);border-radius:var(--radius-sm);margin-bottom:10px;font-size:14px;line-height:1.5;border:1px solid rgba(52,199,89,.15)}.hint-badge{display:inline-block;background:var(--success);color:#fff;font-size:10px;font-weight:600;padding:3px 10px;border-radius:20px;margin-bottom:6px;letter-spacing:-.2px}.feedback{padding:10px 14px;border-radius:var(--radius-sm);margin-bottom:8px;text-align:center;font-size:14px;font-weight:500}.feedback:empty{display:none}.feedback:not(:empty){background:var(--success-light);color:var(--success);border:1px solid rgba(52,199,89,.15)}.options-area{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:10px}.opt-btn{padding:10px 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h2{font-size:22px;font-weight:700;letter-spacing:-.5px;margin-bottom:20px}.summary-section{text-align:left;margin-bottom:16px;padding:16px;background:var(--bg);border-radius:var(--radius-sm)}.summary-section h3{font-size:12px;color:var(--text3);text-transform:uppercase;letter-spacing:.5px;margin-bottom:8px;display:flex;align-items:center;gap:6px;font-weight:600}.summary-section ul{list-style:none;padding:0}.summary-section ul li{padding:4px 0 4px 18px;position:relative;font-size:14px;color:var(--text)}.summary-section ul li:before{content:"·";position:absolute;left:2px;color:var(--primary);font-weight:700;font-size:18px}.summary-section p{font-size:14px;line-height:1.6;color:var(--text)}.summary-formula{font-size:14px;font-weight:600;color:var(--primary);padding:10px 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li:before{content:counter(step);position:absolute;left:-16px;top:12px;width:30px;height:30px;border-radius:50%;background:var(--primary-light);color:var(--primary);display:flex;align-items:center;justify-content:center;font-size:13px;font-weight:700}.answer-text{font-size:16px;font-weight:700;color:var(--primary);padding:14px 18px;background:var(--primary-light);border-radius:var(--radius-sm);margin:14px 0;border:1px solid rgba(0,122,255,.1)}.answer-explain{font-size:14px;color:var(--text2);line-height:1.7}.error-card{text-align:center;padding:80px 20px}.error-card .err-icon{font-size:56px;display:block;margin-bottom:8px}.error-card h2{font-size:20px;font-weight:600;margin-bottom:8px}.error-card p{color:var(--text2);margin-bottom:24px;font-size:14px}@media(max-width:768px){.chat-layout{flex-direction:column;height:auto;min-height:auto}.info-panel{width:100%;flex-direction:row;flex-wrap:wrap;gap:8px;padding:12px;overflow-y:visible}.info-section{flex:1;min-width:90px}.chat-area{height:65vh;min-height:400px}}