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ease;pointer-events:auto;min-width:280px}.toast-success{border-left:4px solid #22c55e}.toast-error{border-left:4px solid #ef4444}.toast-info{border-left:4px solid var(--red)}@keyframes slideIn{0%{opacity:0;transform:translate(40px)}to{opacity:1;transform:translate(0)}}.xp-badge{display:inline-flex;align-items:center;gap:3px;color:var(--gold-dim);font-weight:700;font-size:12px}.difficulty-slider{width:100%;accent-color:var(--red)}.activity-item{display:flex;align-items:flex-start;gap:12px;padding:14px 0;border-bottom:1px solid var(--border)}.activity-item:last-child{border-bottom:none}.activity-dot{width:8px;height:8px;border-radius:50%;background:var(--red);margin-top:5px;flex-shrink:0}.activity-msg{font-size:13px;color:var(--text1);font-weight:500;flex:1}.activity-time{font-size:11.5px;color:var(--text3);white-space:nowrap}.confirm-icon{width:56px;height:56px;border-radius:50%;background:#ef44441a;display:flex;align-items:center;justify-content:center;color:#ef4444;margin:0 auto 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14px;font-size:13px;color:#ef4444;margin-bottom:16px;text-align:center}.loading-spinner{display:flex;align-items:center;justify-content:center;padding:48px}.spinner{width:32px;height:32px;border:3px solid var(--bg4);border-top-color:var(--red);border-radius:50%;animation:spin .8s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.skeleton{background:var(--bg4);border-radius:4px;animation:pulse 1.5s ease-in-out infinite}@keyframes pulse{0%,to{opacity:1}50%{opacity:.5}}.course-title-cell{font-weight:600}