:root{color-scheme:light;--color-ink:#17201d;--color-muted:#5f6864;--color-paper:#fbfbf8;--color-surface:#fff;--color-line:#d7ddd7;--color-green:#2f7d5b;--color-blue:#3469a6;--color-amber:#b87918;--color-coral:#c6543f;--shadow-soft:0 20px 55px #1e2d271f;--radius:8px;--page-gutter:16px;--section-padding:32px;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Microsoft YaHei,sans-serif}*{box-sizing:border-box}body{color:var(--color-ink);background:linear-gradient(90deg, #2f7d5b14, transparent 38%), linear-gradient(180deg, #fff 0%, var(--color-paper) 54%, #eef4f1 100%);margin:0;line-height:1.6}a{color:inherit;text-decoration:none}.site-header{z-index:10;border-bottom:1px solid var(--color-line);backdrop-filter:blur(14px);background:#fbfbf8e6;justify-content:space-between;align-items:center;gap:24px;padding:14px clamp(18px,4vw,56px);display:flex;position:sticky;top:0}.brand,.site-header nav{align-items:center;gap:12px;display:flex}.brand{min-height:44px;font-weight:760}.brand-mark{color:#fff;background:var(--color-green);border-radius:8px;place-items:center;width:34px;height:34px;font-size:.78rem;display:inline-grid}.site-header nav a{min-height:44px;color:var(--color-muted);align-items:center;font-size:.95rem;display:inline-flex}.site-header nav a:hover{color:var(--color-ink)}.site-header nav a[aria-current=page],.site-header nav a.is-active-section{color:var(--color-ink);box-shadow:inset 0 -2px var(--color-green);font-weight:760}main{width:min(1120px, calc(100% - var(--page-gutter) * 2));margin:0 auto}.eyebrow{color:var(--color-green);letter-spacing:0;font-weight:760}.hero{grid-template-columns:minmax(0,1fr) minmax(320px,.86fr);align-items:center;gap:clamp(28px,5vw,64px);min-height:calc(100svh - 74px);padding:56px 0 42px;display:grid}.hero h1,.page-title{letter-spacing:0;max-width:900px;margin:0;font-size:clamp(2.3rem,6vw,5.6rem);line-height:1.02}.hero p,.lede{max-width:720px;color:var(--color-muted);font-size:clamp(1rem,2vw,1.2rem)}.actions{flex-wrap:wrap;gap:12px;margin-top:26px;display:flex}.button{border:1px solid var(--color-line);min-height:44px;color:var(--color-ink);background:var(--color-surface);border-radius:8px;justify-content:center;align-items:center;padding:0 18px;font-weight:720;display:inline-flex}.button.primary{color:#fff;background:var(--color-green);border-color:var(--color-green)}.system-map,.section-band{padding:var(--section-padding);border:1px solid var(--color-line);border-radius:var(--radius);box-shadow:var(--shadow-soft);background:#ffffffc7}.system-map svg{width:100%;height:auto;display:block}.section-band{margin:28px 0 48px}.pill-grid,.demo-grid{grid-template-columns:repeat(4,minmax(0,1fr));gap:12px;display:grid}.pill,.demo-card{border:1px solid var(--color-line);background:var(--color-surface);border-radius:8px;padding:14px}.demo-grid{grid-template-columns:repeat(4,minmax(0,1fr))}.overview-grid{grid-template-columns:repeat(3,minmax(0,1fr))}.demo-card{align-content:start;gap:8px;min-height:170px;transition:border-color .16s,transform .16s;display:grid}.demo-card:hover{border-color:var(--color-green);transform:translateY(-2px)}.demo-card.recommended-card{background:linear-gradient(180deg, #2f7d5b17, transparent 54%), var(--color-surface);border-color:#2f7d5b80}.demo-card small,.card-meta{color:var(--color-green);font-weight:760}.demo-card small{background:#2f7d5b14;border:1px solid #2f7d5b3d;border-radius:8px;width:fit-content;padding:3px 8px;font-size:.78rem;display:inline-flex}.demo-card span{color:var(--color-blue);font-weight:780}.demo-card strong{font-size:1.08rem}.demo-card p{color:var(--color-muted);margin:0}.demo-card p.card-meta{color:var(--color-green)}.chapter-main{padding:54px 0 72px}.timeline-list{gap:14px;margin:34px 0 48px;display:grid}.timeline-item{border:1px solid var(--color-line);background:var(--color-surface);border-radius:8px;grid-template-columns:130px minmax(0,1fr) auto;align-items:center;gap:18px;padding:20px;display:grid}.timeline-item>span{color:var(--color-blue);font-weight:780}.timeline-item h2,.timeline-item p{margin:0}.timeline-item h2{letter-spacing:0;font-size:1.18rem}.timeline-item p:not(.eyebrow){color:var(--color-muted)}.lineage-view-controls{gap:10px;margin:24px 0 14px;display:flex}.lineage-view-controls button{border:1px solid var(--color-line);min-height:44px;color:var(--color-ink);background:var(--color-surface);font:inherit;border-radius:8px;padding:0 16px;font-weight:720}.lineage-view-controls button[aria-pressed=true]{color:#fff;background:var(--color-green);border-color:var(--color-green)}.lineage-panel{-webkit-overflow-scrolling:touch;overscroll-behavior-inline:contain;scrollbar-gutter:stable;border:1px solid var(--color-line);background:var(--color-surface);box-shadow:var(--shadow-soft), inset -18px 0 18px -20px #17201d6b;border-radius:8px;margin:34px 0;padding:22px;overflow-x:hidden}.lineage-panel:focus-visible{outline-offset:3px;outline:3px solid #3469a66b}.lineage-panel svg{width:100%;min-width:0;height:auto;display:block}.lineage-panel[data-view=detail]{overflow-x:auto}.lineage-panel[data-view=detail] svg{min-width:860px}.lineage-panel path[id^=arrow-]{stroke:#9ba9a1;stroke-width:3px}.lineage-panel marker path{fill:#9ba9a1}.lineage-node rect{fill:#fff;stroke:var(--color-line);stroke-width:2px}.lineage-node.symbolic rect{stroke:var(--color-amber)}.lineage-node.statistical rect{stroke:var(--color-green)}.lineage-node.neural rect,.lineage-node.foundation rect{stroke:var(--color-blue)}.lineage-node.agent rect,.lineage-node.safety rect{stroke:var(--color-coral)}.lineage-panel text{fill:var(--color-ink);font-size:14px;font-weight:760}.lineage-panel .node-caption,.lineage-panel .edge-label{fill:var(--color-muted);font-size:10px}.lineage-panel .edge-label{paint-order:stroke;stroke:var(--color-surface);stroke-linejoin:round;stroke-width:5px}.chapter-question{color:var(--color-ink);background:#3469a61a;border:1px solid #3469a633;border-radius:8px;margin:18px 0 0;padding:10px 14px;font-weight:760;display:inline-flex}.llm-map{grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;margin-top:22px;display:grid}.llm-layer{border:1px solid var(--color-line);background:var(--color-surface);border-radius:8px;gap:8px;min-height:198px;padding:18px;display:grid}.llm-layer strong{color:var(--color-blue);font-size:1.08rem}.llm-layer p,.llm-layer small{margin:0}.llm-layer p{color:var(--color-ink)}.llm-layer small{color:var(--color-muted);align-self:end}.llm-layer.base-model{border-color:#b8791880}.llm-layer.context-window{border-color:#3469a680}.llm-layer.eval{border-color:#c6543f80}.compact-list{margin-bottom:0}.compact-item{grid-template-columns:160px minmax(0,1fr)}.compact-item h3,.compact-item p{margin:0}@media (prefers-reduced-motion:reduce){*,:before,:after{scroll-behavior:auto!important;transition-duration:.001ms!important;animation-duration:.001ms!important;animation-iteration-count:1!important}}@media (width<=820px){:root{--section-padding:24px}.site-header{flex-direction:column;align-items:flex-start;gap:8px}.site-header nav{flex-wrap:wrap;gap:4px 14px;width:100%}.hero{grid-template-columns:1fr;min-height:auto}.pill-grid,.demo-grid,.overview-grid{grid-template-columns:1fr 1fr}.timeline-item{grid-template-columns:1fr}.llm-map{grid-template-columns:1fr 1fr}.lineage-view-controls button{flex:1}}@media (width<=520px){:root{--page-gutter:12px;--section-padding:18px}.site-header{padding:10px var(--page-gutter) 8px}.brand{gap:10px}.site-header nav{gap:2px 12px}.hero{padding:42px 0 30px}.hero h1{font-size:3rem}.page-title{font-size:2.35rem;line-height:1.08}.actions .button{flex:150px}.chapter-main{padding:42px 0 56px}.pill-grid,.demo-grid,.overview-grid,.llm-map{grid-template-columns:1fr}}