@keyframes _si{to{opacity:1}}

.legacy-content .three-cols {display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-top:8px}@media(max-width:900px){.legacy-content .three-cols {grid-template-columns:1fr}}.legacy-content .col-card {background:var(--card);border:1.5px solid var(--border);border-radius:var(--radius);padding:22px;box-shadow:var(--shadow-card);display:flex;flex-direction:column}.legacy-content .col-card .col-header {display:flex;align-items:center;gap:10px;margin-bottom:14px}.legacy-content .col-card .col-icon {width:38px;height:38px;border-radius:10px;display:flex;align-items:center;justify-content:center;font-size:18px;flex-shrink:0}.legacy-content .col-card .col-title {font-size:16px;font-weight:800;color:var(--text)}.legacy-content .col-card .col-desc {font-size:13px;color:var(--sub);line-height:1.6;margin-bottom:14px}.legacy-content .strategy-item {padding:10px 14px;border-radius:var(--radius-sm);margin-bottom:8px;cursor:pointer;transition:all .25s;border:1px solid transparent}.legacy-content .strategy-item:hover {border-color:var(--border);background:rgba(0,0,0,.02)}.legacy-content .strategy-item .s-name {font-size:14px;font-weight:700;color:var(--text);margin-bottom:2px}.legacy-content .strategy-item .s-desc {font-size:12px;color:var(--sub);line-height:1.5;max-height:0;overflow:hidden;transition:max-height .3s ease,margin .3s ease}.legacy-content .strategy-item.open .s-desc {max-height:100px;margin-top:6px}.legacy-content .strategy-item .s-toggle {font-size:11px;color:var(--accent);font-weight:600;margin-top:4px}.legacy-content .col-card.hard .col-icon {background:rgba(220,38,38,.08);color:var(--danger)}.legacy-content .col-card.hard .strategy-item:hover {background:rgba(220,38,38,.03)}.legacy-content .col-card.detect .col-icon {background:rgba(217,119,6,.08);color:var(--amber)}.legacy-content .col-card.detect .strategy-item:hover {background:rgba(217,119,6,.03)}.legacy-content .col-card.degrade .col-icon {background:rgba(22,163,74,.08);color:var(--success)}.legacy-content .col-card.degrade .strategy-item:hover {background:rgba(22,163,74,.03)}.legacy-content .layer-diagram {margin-top:20px;background:var(--card);border:1.5px solid var(--border);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow-card)}.legacy-content .layer-diagram h3 {font-size:16px;font-weight:800;color:var(--text);margin-bottom:16px;text-align:center}.legacy-content .layers {display:flex;flex-direction:column;gap:0;align-items:center}.legacy-content .layer {width:100%;max-width:500px;padding:14px 20px;text-align:center;font-size:14px;font-weight:700;border-radius:var(--radius-sm);position:relative;transition:all .3s}.legacy-content .layer:not(:last-child)::after {content:'↓';position:absolute;bottom:-14px;left:50%;transform:translateX(-50%);font-size:14px;color:var(--sub);z-index:1}.legacy-content .layer-gap {height:20px}.legacy-content .layer.l1 {background:rgba(22,163,74,.08);border:1.5px solid rgba(22,163,74,.2);color:var(--success)}.legacy-content .layer.l2 {background:rgba(217,119,6,.08);border:1.5px solid rgba(217,119,6,.2);color:var(--amber)}.legacy-content .layer.l3 {background:rgba(220,38,38,.08);border:1.5px solid rgba(220,38,38,.2);color:var(--danger)}.legacy-content .layer-label {font-size:11px;font-weight:600;color:var(--sub);margin-top:4px}.legacy-content .takeaway {background:rgba(0,102,255,.04);border:1.5px solid rgba(0,102,255,.18);border-radius:var(--radius);padding:16px 20px;font-size:15px;color:var(--text);display:flex;gap:10px;line-height:1.7;margin-top:24px}.legacy-content .takeaway b {color:var(--accent)}