/* ============================================================
   MCM ROBOTICS v3 — /robot-brain/ (TX series robot brains)
   Page-only components, prefixed rb-. Tokens, type, buttons,
   .instrument, .spec-table and bands come from main.css.
   ============================================================ */

.rb-page { overflow-x: clip; }

/* ---------- hero ---------- */
.rb-hero { position: relative; overflow: hidden; padding: calc(var(--nav-h) + clamp(40px, 6vw, 80px)) 0 clamp(40px, 6vw, 72px); }
.rb-hero-grid { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: clamp(28px, 4vw, 56px); align-items: center; }
.rb-hero h1 { margin-top: 18px; }
.rb-hero h1 em { font-style: normal; color: var(--void-accent); }
.rb-hero .lead { margin-top: 22px; color: var(--void-muted); }
.rb-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }
.rb-boards { position: relative; aspect-ratio: 1 / 0.92; }
.rb-boards::before { content: ""; position: absolute; inset: 8% 4% 4% 8%; background: radial-gradient(closest-side, rgba(125, 211, 252, 0.22), transparent 72%); }
.rb-boards img { position: absolute; height: auto; filter: drop-shadow(0 30px 40px rgba(0, 0, 0, 0.55)); }
.rb-boards .rb-b1 { width: 74%; top: 6%; left: 0; }
.rb-boards .rb-b2 { width: 56%; bottom: 4%; right: 0; }
.rb-tag { position: absolute; z-index: 2; font-family: var(--font-mono); font-size: 0.66rem; letter-spacing: 0.16em; text-transform: uppercase; color: var(--void-ink); background: rgba(5, 7, 11, 0.78); border: 1px solid var(--void-line); padding: 6px 10px; border-radius: 2px; }
.rb-tag b { color: var(--void-accent); font-weight: 500; }
.rb-tag-1 { top: 0; left: 4%; }
.rb-tag-2 { bottom: 0; right: 4%; }
.rb-hero .instrument { margin-top: clamp(40px, 6vw, 64px); grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); }
@media (max-width: 900px) { .rb-hero-grid { grid-template-columns: 1fr; } .rb-boards { max-width: 560px; } }

/* ---------- section heads ---------- */
.rb-head { display: grid; gap: 18px; margin-bottom: clamp(32px, 5vw, 56px); max-width: 780px; }
.rb-head .lead { max-width: 62ch; }
.band-dark .rb-head .lead { color: var(--void-muted); }
.rb-sub { margin-top: clamp(56px, 8vw, 96px); display: grid; gap: 14px; max-width: 780px; }
.band-dark .rb-sub .lead { color: var(--void-muted); }

/* ---------- brain + cerebellum ---------- */
.rb-facts { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-bottom: clamp(28px, 4vw, 44px); }
@media (max-width: 900px) { .rb-facts { grid-template-columns: 1fr; } }
.rb-fact { display: grid; grid-template-columns: 46px 1fr; gap: 14px; align-items: start; }
.rb-fact .n { font-family: var(--font-mono); font-size: 0.72rem; color: var(--primary); border: 1px solid var(--primary); border-radius: 2px; text-align: center; padding: 4px 0; }
.rb-fact h3 { font-family: var(--font-display); font-weight: 700; font-size: 1.05rem; }
.rb-fact p { color: var(--muted); font-size: 0.95rem; margin-top: 2px; }
.rb-diagram { background: var(--surface); border: 1px solid var(--line-2); border-radius: var(--r-card); padding: clamp(14px, 2.4vw, 26px); overflow-x: auto; }
.rb-diagram svg { width: 100%; height: auto; min-width: 560px; }
.rb-diagram.rb-loop svg { min-width: 0; }
.rb-diagram figcaption { margin-top: 12px; font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.08em; color: var(--faint); }
.dg-box { fill: var(--surface-2); stroke: var(--line-2); }
.dg-brain { fill: var(--primary-subtle); stroke: var(--primary); }
.dg-cereb { fill: #ecfdf5; stroke: var(--good); }
.dg-cloud { fill: var(--surface); stroke: var(--ink-2); stroke-dasharray: 5 4; }
.dg-t { font-family: var(--font-display); font-weight: 700; font-size: 15px; fill: var(--ink); }
.dg-s { font-family: var(--font-mono); font-size: 10.5px; fill: var(--muted); letter-spacing: 0.04em; }
.dg-k { font-family: var(--font-mono); font-size: 10px; fill: var(--primary); letter-spacing: 0.14em; }
.dg-line { stroke: var(--ink-2); stroke-width: 1.5; fill: none; }
.dg-line.dash { stroke-dasharray: 5 4; }
.dg-arrow { fill: var(--ink-2); }

/* ---------- fits Unitree ---------- */
.rb-fits { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
@media (max-width: 860px) { .rb-fits { grid-template-columns: 1fr; max-width: 520px; } }
.rb-fit { background: var(--surface); border: 1px solid var(--line-2); border-radius: var(--r-card); overflow: hidden; display: grid; transition: border-color 0.18s, transform 0.18s var(--ease-out); }
@media (hover: hover) { .rb-fit:hover { border-color: var(--primary); transform: translateY(-2px); } }
.rb-fit-img { background: linear-gradient(180deg, #fff, var(--surface-2)); aspect-ratio: 16 / 10; padding: 14px; border-bottom: 1px solid var(--line); }
.rb-fit-img img { width: 100%; height: 100%; object-fit: contain; }
.rb-fit-body { padding: 18px 20px 20px; display: grid; gap: 6px; }
.rb-fit-body h3 { font-family: var(--font-display); font-weight: 800; font-stretch: 88%; font-size: 1.45rem; }
.rb-fit-body p { color: var(--muted); font-size: 0.93rem; }
.rb-fit-body .go { font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.14em; text-transform: uppercase; color: var(--primary); margin-top: 6px; }

/* ---------- models ---------- */
.rb-models { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
@media (max-width: 980px) { .rb-models { grid-template-columns: 1fr; max-width: 560px; } }
.rb-model { background: var(--surface); border: 1px solid var(--line-2); border-radius: var(--r-card); display: flex; flex-direction: column; overflow: hidden; }
.rb-model-img { background: linear-gradient(180deg, #fff, var(--surface-2)); aspect-ratio: 3 / 2; overflow: hidden; padding: 10px; border-bottom: 1px solid var(--line); }
.rb-model-img img { width: 100%; height: 100%; object-fit: contain; }
.rb-model-body { padding: 22px 22px 24px; display: grid; gap: 14px; flex: 1; align-content: start; }
.rb-model-top { display: flex; justify-content: space-between; align-items: baseline; gap: 10px; flex-wrap: wrap; }
.rb-model h3 { font-family: var(--font-display); font-weight: 800; font-stretch: 88%; font-size: 1.9rem; letter-spacing: 0.01em; }
.rb-role { font-family: var(--font-mono); font-size: 0.68rem; letter-spacing: 0.16em; text-transform: uppercase; color: var(--primary); }
.rb-model p { color: var(--muted); font-size: 0.95rem; }
.rb-kv { display: grid; grid-template-columns: auto 1fr; gap: 6px 14px; font-size: 0.88rem; border-top: 1px solid var(--line); padding-top: 14px; margin: 0; }
.rb-kv dt { font-family: var(--font-mono); font-size: 0.72rem; color: var(--faint); padding-top: 2px; }
.rb-kv dd { margin: 0; color: var(--ink-2); font-variant-numeric: tabular-nums; }
.rb-best { margin-top: auto; background: var(--surface-2); border-left: 3px solid var(--primary); padding: 10px 12px; font-size: 0.88rem; color: var(--ink-2); }
.rb-best b { font-family: var(--font-mono); font-size: 0.66rem; letter-spacing: 0.16em; text-transform: uppercase; color: var(--primary); display: block; margin-bottom: 2px; font-weight: 500; }

/* ---------- navigation ---------- */
.rb-steps { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--void-line); border-left: 1px solid var(--void-line); }
@media (max-width: 900px) { .rb-steps { grid-template-columns: 1fr 1fr; } }
@media (max-width: 600px) { .rb-steps { grid-template-columns: 1fr; } }
.rb-step { border-right: 1px solid var(--void-line); border-bottom: 1px solid var(--void-line); padding: 26px 22px 28px; display: grid; gap: 10px; align-content: start; }
.rb-step .num { font-family: var(--font-display); font-weight: 820; font-stretch: 76%; font-size: 2.6rem; line-height: 0.9; color: var(--void-accent); }
.rb-step h3 { font-family: var(--font-display); font-weight: 700; font-size: 1.15rem; color: var(--void-ink); }
.rb-step p { color: var(--void-muted); font-size: 0.93rem; }
.rb-step .tech { font-family: var(--font-mono); font-size: 0.66rem; letter-spacing: 0.1em; text-transform: uppercase; color: #cbd5e1; opacity: 0.75; }
.rb-photos { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: 12px; margin-top: 28px; }
@media (max-width: 760px) { .rb-photos { grid-template-columns: 1fr; } }
.rb-follow { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin-top: 26px; }
@media (max-width: 760px) { .rb-follow { grid-template-columns: 1fr; } }
.rb-photo { position: relative; border-radius: var(--r-card); overflow: hidden; background: var(--void-2); margin: 0; }
.rb-photo img { width: 100%; height: 100%; object-fit: cover; aspect-ratio: 16 / 10; }
.rb-follow .rb-photo img { aspect-ratio: 1392 / 720; }
.rb-photo figcaption { position: absolute; left: 10px; bottom: 10px; font-family: var(--font-mono); font-size: 0.64rem; letter-spacing: 0.12em; text-transform: uppercase; color: var(--void-ink); background: rgba(5, 7, 11, 0.72); padding: 6px 9px; border-radius: 2px; max-width: calc(100% - 20px); }
.rb-dual { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-top: 26px; }
@media (max-width: 760px) { .rb-dual { grid-template-columns: 1fr; } }
.rb-dual-card { border: 1px solid var(--void-line); border-radius: var(--r-card); padding: 22px; background: var(--void-2); display: grid; gap: 10px; align-content: start; }
.rb-dual-card .k { font-family: var(--font-mono); font-size: 0.66rem; letter-spacing: 0.18em; text-transform: uppercase; color: var(--void-accent); }
.rb-dual-card h4 { font-family: var(--font-display); font-weight: 700; font-size: 1.15rem; color: var(--void-ink); }
.rb-dual-card p { color: var(--void-muted); font-size: 0.93rem; }
.rb-fallback { margin-top: 12px; border: 1px solid rgba(125, 211, 252, 0.35); border-radius: var(--r-card); padding: 16px 20px; display: flex; gap: 14px; align-items: flex-start; color: var(--void-ink); font-size: 0.95rem; }
.rb-fallback .chip-label { background: var(--void-accent); color: var(--void); flex: none; }

/* ---------- platform ---------- */
.rb-split { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(28px, 5vw, 72px); align-items: center; }
@media (max-width: 900px) { .rb-split { grid-template-columns: 1fr; } }
.rb-ticks { list-style: none; padding: 0; margin: 24px 0 0; display: grid; gap: 12px; }
.rb-ticks li { display: grid; grid-template-columns: 22px 1fr; gap: 10px; color: var(--ink-2); }
.rb-ticks li::before { content: ""; width: 14px; height: 14px; margin-top: 5px; border: 2px solid var(--primary); border-radius: 2px; background: linear-gradient(var(--primary), var(--primary)) center / 6px 6px no-repeat; }
.rb-ticks b { font-weight: 600; color: var(--ink); }

/* ---------- applications ---------- */
.rb-apps { display: grid; grid-template-columns: repeat(6, 1fr); gap: 16px; }
.rb-app { grid-column: span 2; background: var(--surface); border: 1px solid var(--line-2); border-radius: var(--r-card); overflow: hidden; display: flex; flex-direction: column; }
.rb-app.wide { grid-column: span 3; }
@media (max-width: 980px) { .rb-app, .rb-app.wide { grid-column: span 3; } }
@media (max-width: 640px) { .rb-apps { grid-template-columns: 1fr; } .rb-app, .rb-app.wide { grid-column: auto; } }
.rb-app > img { width: 100%; height: auto; aspect-ratio: 16 / 10; object-fit: cover; }
.rb-app .noimg { aspect-ratio: 16 / 10; background: var(--void); display: grid; place-items: center; }
.rb-app .noimg svg { width: 62%; height: auto; }
.rb-app-body { padding: 20px 20px 22px; display: grid; gap: 10px; }
.rb-app h3 { font-family: var(--font-display); font-weight: 750; font-size: 1.2rem; }
.rb-app p { color: var(--muted); font-size: 0.93rem; }
.rb-app .where { font-family: var(--font-mono); font-size: 0.68rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--primary); }

/* ---------- specs extras ---------- */
.rb-specs .spec-table { min-width: 720px; }
.rb-specs .na { color: var(--faint); }
.rb-ifaces { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 22px; }
.rb-iface { font-family: var(--font-mono); font-size: 0.74rem; padding: 7px 11px; border: 1px solid var(--line-2); border-radius: 2px; background: var(--surface); color: var(--ink-2); }

/* ---------- contact ---------- */
.rb-cta { display: grid; grid-template-columns: 1.2fr 1fr; gap: clamp(28px, 5vw, 64px); align-items: start; }
@media (max-width: 900px) { .rb-cta { grid-template-columns: 1fr; } }
.rb-cta .lead { color: var(--void-muted); }
.rb-branch { border-top: 1px solid var(--void-line); padding-block: 16px; display: grid; gap: 4px; }
.rb-branch h3 { font-family: var(--font-display); font-weight: 700; font-size: 1rem; text-transform: uppercase; letter-spacing: 0.02em; color: var(--void-ink); }
.rb-branch a, .rb-branch span { color: var(--void-muted); font-size: 0.93rem; }
.rb-branch a:hover { color: var(--void-ink); }