.theory-container{max-width:820px}.theory-view{margin-top:8px}.theory-tabs{border-bottom:1px solid #e4eaf0;gap:4px;margin-bottom:20px;display:flex;overflow-x:auto}.theory-tabs button{color:#667085;white-space:nowrap;cursor:pointer;background:0 0;border:0;border-bottom:2px solid #0000;padding:12px 16px;font-size:13px;font-weight:700}.theory-tabs button.active{color:#1976d2;border-color:#1976d2}.theory-overview{color:#435263;background:#f7f9fc;border-radius:10px;margin:0 0 20px;padding:16px 18px;font-size:14px;line-height:1.7}.theory-list{flex-direction:column;gap:8px;display:flex}.theory-item{background:#fff;border:1px solid #e1e8ee;border-radius:10px;overflow:hidden}.theory-item summary{cursor:pointer;color:#122b45;justify-content:space-between;align-items:center;gap:10px;padding:15px 18px;font-size:14px;font-weight:700;list-style:none;display:flex}.theory-item summary::-webkit-details-marker{display:none}.theory-item summary svg{color:#8c98a4;flex-shrink:0;width:16px;transition:all .2s}.theory-item summary svg.rotate{transform:rotate(180deg)}.theory-item-body{color:#435263;border-top:1px solid #edf1f4;margin-top:-2px;padding:14px 18px 18px;font-size:13px;line-height:1.7}.theory-empty{color:#8a97a4;text-align:center;padding:30px 0;font-size:13px}@media (max-width:620px){.theory-tabs button{padding:10px 12px;font-size:12px}}