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a.is-active{color:var(--brand);background:var(--surface-2);font-weight:600}.article-body{min-width:0;max-width:840px;color:var(--text);font-size:1.02rem;line-height:1.68}.article-section{margin-bottom:32px;padding-top:8px;scroll-margin-top:96px}.article-section h2{letter-spacing:-.01em;color:var(--text);margin:0 0 16px;font-size:1.7rem;line-height:1.25}.article-section h3{color:var(--text);margin:32px 0 12px;font-size:1.25rem}.article-section h4{color:var(--text);margin:24px 0 8px;font-size:1.05rem}.article-section p{color:var(--muted);margin:0 0 16px}.article-section strong{color:var(--text)}.article-section code{background:var(--surface-2);border:1px solid var(--line);border-radius:4px;padding:1px 5px;font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;font-size:.85em}.styled-list{color:var(--muted);margin:0 0 20px;padding-left:20px}.styled-list li{margin-bottom:8px;line-height:1.55}.styled-list strong{color:var(--text)}.section-divider{border:none;border-top:1px solid var(--line);margin:48px 0}.diagram-box{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-md,10px);margin:24px 0;overflow:hidden}.diagram-header{background:var(--surface-2);border-bottom:1px solid var(--line);color:var(--muted);justify-content:space-between;align-items:center;padding:10px 16px;font-size:.82rem;font-weight:700;display:flex}.diagram-tag{background:var(--line);border-radius:4px;padding:2px 8px;font-size:.72rem;font-weight:600}.diagram-title{color:#38bdf8;text-transform:uppercase;letter-spacing:.05em;font-size:.85rem;font-weight:700}.ascii-art{color:#f1f5f9;background:#0f172a;margin:0;padding:16px;font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;font-size:.8rem;line-height:1.5;overflow-x:auto}.code-figure{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-md,10px);margin:24px 0;overflow:hidden}.code-figure-header{background:var(--surface-2);border-bottom:1px solid var(--line);color:var(--muted);justify-content:space-between;align-items:center;padding:10px 16px;font-size:.82rem;font-weight:700;display:flex}.code-lang{background:var(--line);border-radius:4px;padding:2px 8px;font-size:.72rem;font-weight:600}.code-figure pre{color:var(--text);margin:0;padding:16px;font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;font-size:.84rem;line-height:1.5;overflow-x:auto}.info-callout,.warning-callout,.success-callout,.callout,.lens-callout{border-radius:var(--radius-md,10px);margin:24px 0;padding:18px 22px;font-size:.95rem;line-height:1.6}.lens-callout{background:color-mix(in srgb, var(--brand) 8%, var(--surface));border:1px solid var(--line)}.lens-callout p:last-child{margin-bottom:0}.info-callout{background:color-mix(in srgb, var(--brand) 8%, var(--surface));border:1px solid color-mix(in srgb, var(--brand) 25%, transparent)}.info-callout strong{color:var(--brand)}.warning-callout{background:#ea580c14;border:1px solid #ea580c40}.warning-callout strong{color:#ea580c}.info-callout ul,.warning-callout ul{margin:10px 0 0;padding-left:20px}.info-callout li,.warning-callout li{margin-bottom:6px}.success-callout{background:#10b98114;border:1px solid #10b98140}.success-callout strong{color:#10b981}.lens-badge{text-transform:uppercase;letter-spacing:.05em;border-radius:4px;align-items:center;gap:4px;margin-bottom:8px;padding:2px 8px;font-size:.72rem;font-weight:700;display:inline-flex}.lens-badge-foundations{color:#059669;background:#10b9811f;border:1px solid #10b98140}.lens-badge-deep{color:#4f46e5;background:#6366f11f;border:1px solid #6366f140}.badge-icon{flex-shrink:0;width:14px;height:14px;display:inline-block}.heading-icon{vertical-align:-.18em;width:1.1em;height:1.1em;color:var(--brand);margin-right:6px;display:inline-block}.heading-icon.text-danger{color:#ef4444}.heading-icon.text-brand{color:var(--brand)}.drawer-icon{background:var(--surface-2);width:28px;height:28px;color:var(--brand);border-radius:6px;flex-shrink:0;justify-content:center;align-items:center;display:inline-flex}.drawer-icon-svg{width:16px;height:16px}.status-icon{vertical-align:-2px;flex-shrink:0;width:15px;height:15px;margin-right:6px;display:inline-block}.status-icon.success{color:#10b981}.status-icon.danger{color:#ef4444}.status-icon.warning{color:#f59e0b}.inline-btn-icon{vertical-align:-2px;width:15px;height:15px;margin-left:6px}.features-grid{grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:20px;margin:24px 0;display:grid}.feature-item{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-md,10px);padding:20px}.feature-item h4{margin:0 0 8px;font-size:1.05rem}.feature-item p{color:var(--muted);margin:0;font-size:.92rem}.feature-item p+p{margin-top:10px}.table-container{border:1px solid var(--line);border-radius:var(--radius-md,10px);background:var(--surface);margin:24px 0;overflow-x:auto}.comparison-table{border-collapse:collapse;text-align:left;width:100%;font-size:.9rem}.comparison-table th,.comparison-table td{border-bottom:1px solid var(--line);padding:14px 18px}.comparison-table th{background:var(--surface-2);color:var(--text);font-weight:700}.comparison-table tr:last-child td{border-bottom:none}.takeaways-box{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-md,10px);margin:32px 0;padding:24px}.takeaways-box h3{color:var(--brand);margin:0 0 16px;font-size:1.2rem}.takeaways-box ol,.takeaways-box ul{color:var(--muted);margin:0;padding-left:20px}.takeaways-box li{margin-bottom:10px;line-height:1.5}.takeaways-box li:last-child{margin-bottom:0}.article-footer-nav{border-top:1px solid var(--line);flex-wrap:wrap;justify-content:space-between;gap:16px;margin-top:48px;padding-top:24px;display:flex}.deep-dive-drawer{background:var(--surface);border:1px solid var(--line);border-radius:12px;margin:24px 0;transition:border-color .2s,box-shadow .2s;overflow:hidden}.deep-dive-drawer[open]{border-color:var(--brand);box-shadow:0 4px 16px #00000014}.drawer-summary{background:var(--surface-2);cursor:pointer;user-select:none;align-items:center;gap:12px;padding:16px 20px;font-weight:700;display:flex}.drawer-summary::-webkit-details-marker{display:none}.drawer-title{color:var(--text);flex:1;font-size:.98rem}.drawer-pill{background:color-mix(in srgb, var(--brand) 15%, transparent);color:var(--brand);text-transform:uppercase;letter-spacing:.04em;border-radius:4px;padding:3px 8px;font-size:.72rem;font-weight:700}.drawer-content{border-top:1px solid var(--line);padding:20px}.drawer-content p{margin-bottom:14px}.drawer-content p:last-child{margin-bottom:0}[data-lens=beginner] .lens-deep,[data-lens=beginner] .deep-dive-only,[data-lens=deep] .lens-basic,[data-lens=deep] .foundations-only{display:none!important}.section-header-tag{border-bottom:2px solid var(--line);align-items:baseline;gap:12px;margin-bottom:16px;padding-bottom:8px;display:flex}.section-num{color:var(--brand);font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;font-size:1.5rem;font-weight:900}.section-header-tag h2{margin:0;font-size:1.6rem}.concept-cards-grid{grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:16px;margin:24px 0;display:grid}.card-feature{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-md,10px);padding:18px}.card-num{color:var(--brand);margin-bottom:6px;font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;font-size:1.2rem;font-weight:900}.card-feature h3{margin:0 0 8px;font-size:1rem}.card-feature p{color:var(--muted);margin:0;font-size:.85rem;line-height:1.45}@media (width<=900px){.article-layout{grid-template-columns:1fr;gap:32px}.article-sidebar{display:none}.cert-grid,.features-grid,.checklist-grid,.firewall-grid{grid-template-columns:1fr}}