/* lingshu-v2 · site.css · imports tokens.css first */
@import "./tokens.css";

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { background: var(--ls-ink); color: var(--ls-text); font-family: var(--ls-font-ui); line-height: 1.7; overflow-x: clip; -webkit-font-smoothing: antialiased; scroll-padding-top: var(--ls-nav-height); }
html[data-motion=full] { scroll-behavior: smooth; }
body { background: var(--ls-ink); }
img, svg { max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; cursor: pointer; }
ul, ol { list-style: none; }
:focus-visible { outline: 3px solid var(--ls-focus); outline-offset: 4px; }

/* ─── skip link ─── */
.skip-link { position: fixed; left: 16px; top: -80px; z-index: 200; padding: 10px 18px; border-radius: 4px; background: var(--ls-lime); color: #090b0f; font-weight: 700; transition: top .2s; }
.skip-link:focus { top: 12px; }

/* ─── progress bar ─── */
#progress { position: fixed; inset: 0 0 auto 0; height: 2px; background: linear-gradient(90deg, var(--ls-lime), var(--ls-cyan)); transform: scaleX(0); transform-origin: left; z-index: 150; pointer-events: none; }

/* ─── nav ─── */
.site-nav { background: rgba(9,11,15,.94); position: fixed; inset: 0 0 auto 0; height: var(--ls-nav-height); z-index: var(--ls-z-header); display: flex; align-items: center; justify-content: space-between; padding: 0 var(--ls-page-gutter); border-bottom: 1px solid transparent; transition: background 240ms, border-color 240ms; }
.site-nav.scrolled { background: rgba(9,11,15,.88); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); border-color: var(--ls-line); }
.nav-brand { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 18px; letter-spacing: -.02em; }
.nav-brand-mark { width: 28px; height: 28px; background: var(--ls-lime); clip-path: polygon(0 0, 100% 0, 100% 60%, 60% 100%, 0 100%); flex-shrink: 0; }
.nav-links { display: flex; align-items: center; gap: 32px; font-size: 14px; color: var(--ls-text-muted); }
.nav-links a { padding: 8px 0; transition: color 160ms; position: relative; }
.nav-links a:hover, .nav-links a[aria-current=page] { color: var(--ls-text); }
.nav-links a[aria-current=page]::after { content: ''; position: absolute; left: 0; right: 0; bottom: 4px; height: 1px; background: var(--ls-lime); }
.nav-cta { display: inline-flex; align-items: center; gap: 8px; height: 40px; padding: 0 18px; border-radius: var(--ls-radius-control); background: var(--ls-lime); color: #090b0f; font-size: 14px; font-weight: 700; border: none; transition: opacity 160ms; }
.nav-cta:hover { opacity: .88; }
.nav-menu-btn { display: none; border: 1px solid var(--ls-line); background: transparent; border-radius: 4px; padding: 8px 12px; color: var(--ls-text); }
.nav-drawer { display: none; }
.nav-drawer:not([hidden]) { display: block; position: fixed; inset: var(--ls-nav-height, 56px) 0 0 0; background: rgba(9,11,15,.97); z-index: 50; padding: 24px var(--ls-page-gutter); overflow-y: auto; }
.nav-drawer ul { list-style: none; display: flex; flex-direction: column; gap: 8px; }
.nav-drawer a, .nav-drawer button { display: block; padding: 12px 0; font-size: 18px; font-weight: 600; color: var(--ls-text); text-decoration: none; border-bottom: 1px solid var(--ls-line); }

/* ─── section base ─── */
.ls-page { max-width: var(--ls-page-max); margin-inline: auto; padding-inline: var(--ls-page-gutter); }

/* ═══════════════════════════════════════
   § 1 HERO – 品牌舞台（石墨深色）
═══════════════════════════════════════ */
.hero { position: relative; min-height: 100vh; min-height: 100svh; background: var(--ls-ink); display: grid; grid-template-rows: 1fr auto; overflow: hidden; padding-top: var(--ls-nav-height); }
.hero-stage { position: relative; z-index: var(--ls-z-content); display: grid; grid-template-columns: 5fr 7fr; align-items: center; gap: var(--ls-grid-gap); padding-block: clamp(48px,8vh,96px); }
.hero-copy { display: flex; flex-direction: column; justify-content: center; }
.hero-eyebrow { font: 500 11px/1.5 var(--ls-font-mono); letter-spacing: .16em; color: var(--ls-text-muted); margin-bottom: 20px; }
.hero-title { font-family: var(--ls-font-display); font-size: clamp(3.2rem,8vw,7.5rem); line-height: 1.02; font-weight: 800; letter-spacing: -.055em; margin-bottom: 20px; }
.hero-desc { color: var(--ls-text-muted); font-size: clamp(15px,1.3vw,17px); line-height: 1.75; margin-bottom: 36px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.btn-primary { display: inline-flex; align-items: center; gap: 8px; height: var(--ls-control-height); padding: 0 var(--ls-control-pad-x); border-radius: var(--ls-radius-control); background: var(--ls-lime); color: #090b0f; font-size: 15px; font-weight: 700; border: none; transition: opacity 160ms; }
.btn-primary:hover { opacity: .88; }
.btn-ghost { display: inline-flex; align-items: center; gap: 8px; height: var(--ls-control-height); padding: 0 var(--ls-control-pad-x); border-radius: var(--ls-radius-control); background: transparent; color: var(--ls-text); font-size: 15px; font-weight: 600; border: 1px solid var(--ls-line); transition: border-color 160ms, color 160ms; }
.btn-ghost:hover { border-color: var(--ls-text-muted); color: var(--ls-text); }
.hero-canvas-wrap { position: relative; width: 100%; aspect-ratio: 1/.9; }
.hero-canvas { position: absolute; inset: 0; width: 100%; height: 100%; display: block; }
.hero-canvas[hidden] { display: none; }
.hero-fallback { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: contain; object-position: center; }
.hero-layers { position: absolute; right: -8px; top: 50%; transform: translateY(-50%); display: flex; flex-direction: column; gap: 22px; z-index: 2; }
/* P1 hero layer buttons – min 44px touch target */
.hero-layer-btn { display: flex; align-items: center; gap: 10px; min-height: 44px; padding: 0 14px; background: rgba(9,11,15,.7); border: 1px solid var(--ls-line); border-radius: 4px; font: 500 11px/1.4 var(--ls-font-mono); letter-spacing: .12em; color: var(--ls-text-muted); cursor: pointer; transition: border-color 160ms, color 160ms; white-space: nowrap; }
.hero-layer-btn::before { content: '—'; color: var(--ls-lime); font-size: 8px; }
.hero-layer-btn:hover, .hero-layer-btn[aria-pressed=true] { border-color: var(--ls-lime); color: var(--ls-text); }
.hero-drag-hint { position: absolute; left: 50%; bottom: 24px; transform: translateX(-50%); display: flex; align-items: center; gap: 8px; font: 500 11px/1 var(--ls-font-mono); letter-spacing: .14em; color: var(--ls-text-muted); opacity: .7; pointer-events: none; }

/* service tabs */
.service-tabs { display: grid; grid-template-columns: repeat(4,1fr); border-top: 1px solid var(--ls-line); }
.service-tab { display: flex; align-items: center; gap: 12px; padding: 20px var(--ls-page-gutter); font-size: 14px; font-weight: 600; color: var(--ls-text-muted); border: none; background: transparent; border-right: 1px solid var(--ls-line); cursor: pointer; transition: color 160ms; position: relative; }
.service-tab:last-child { border-right: none; }
.service-tab .tab-no { font: 500 10px/1 var(--ls-font-mono); letter-spacing: .14em; }
.service-tab[aria-selected=true] { color: var(--ls-text); }
.service-tab[aria-selected=true]::after { content: ''; position: absolute; left: var(--ls-page-gutter); right: 0; top: 0; height: 2px; background: var(--ls-lime); }
.tab-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--ls-lime); flex-shrink: 0; box-shadow: 0 0 8px var(--ls-lime); }
.scroll-hint { display: flex; align-items: center; gap: 8px; padding: 20px var(--ls-page-gutter); font: 500 10px/1 var(--ls-font-mono); letter-spacing: .14em; color: var(--ls-text-muted); }

/* ═══════════════════════════════════════
   § 2 CAPABILITY STAGE（黑色能力舞台）
═══════════════════════════════════════ */
.cap-stage { background: var(--ls-ink-raised); padding-block: clamp(60px,8vw,100px); border-top: 1px solid var(--ls-line); }
.cap-head { display: grid; grid-template-columns: 1fr auto; align-items: start; gap: 24px; margin-bottom: 40px; }
.cap-eyebrow { font: 500 11px/1.5 var(--ls-font-mono); letter-spacing: .16em; color: var(--ls-text-muted); margin-bottom: 12px; }
.cap-title { font-family: var(--ls-font-display); font-size: clamp(2rem,4.5vw,4.5rem); font-weight: 800; letter-spacing: -.04em; line-height: 1.1; }
.cap-badge { display: inline-flex; align-items: center; gap: 8px; padding: 8px 16px; border-radius: 20px; border: 1px solid var(--ls-line); font-size: 13px; color: var(--ls-text-muted); white-space: nowrap; }
.cap-badge::before { content: ''; width: 6px; height: 6px; border-radius: 50%; background: var(--ls-cyan); box-shadow: 0 0 8px var(--ls-cyan); flex-shrink: 0; }
.cap-body { display: grid; grid-template-columns: 3fr 1fr; gap: 32px; align-items: start; }
.cap-disclosure { margin-bottom: 20px; font-size: 12px; color: var(--ls-text-muted); padding: 10px 16px; border-left: 2px solid var(--ls-line); }
.workflow-panel { background: var(--ls-ink-panel); border: 1px solid var(--ls-line); border-radius: var(--ls-radius-panel); overflow: hidden; }
.workflow-bar { display: flex; align-items: center; justify-content: space-between; padding: 14px 20px; border-bottom: 1px solid var(--ls-line); }
.workflow-title { font-size: 14px; font-weight: 600; }
.workflow-controls { display: flex; gap: 8px; }
.workflow-btn { display: inline-flex; align-items: center; gap: 6px; height: 34px; padding: 0 14px; border-radius: var(--ls-radius-control); font-size: 13px; font-weight: 600; border: 1px solid var(--ls-line); background: transparent; color: var(--ls-text-muted); transition: all 160ms; }
.workflow-btn.active { background: var(--ls-lime); color: #090b0f; border-color: transparent; }
.workflow-inner { padding: 24px 20px; min-height: 280px; }
.workflow-nodes { display: grid; grid-template-columns: 1fr 24px 1fr 24px 1fr 24px 1fr; gap: 0; align-items: start; }
.wf-connector { width: 24px; height: 24px; margin-top: 20px; flex-shrink: 0; }
.wf-node { background: var(--ls-ink); border: 1px solid var(--ls-line); border-radius: 6px; padding: 16px; transition: border-color 200ms, background 200ms; }
.wf-node:hover { border-color: var(--ls-lime); }
.wf-node.wf-active { border-color: var(--ls-lime); background: rgba(214,255,77,.06); }
.wf-node.wf-done { border-color: var(--ls-line); opacity: .55; }
.wf-node.wf-error { border-color: #ff4d4d; background: rgba(255,77,77,.06); }
.wf-node-icon { width: 32px; height: 32px; background: var(--ls-ink-panel); border-radius: 6px; display: flex; align-items: center; justify-content: center; margin-bottom: 10px; }
.wf-node-icon svg { width: 16px; height: 16px; stroke: var(--ls-lime); stroke-width: 1.5; fill: none; }
.wf-node-title { font-size: 13px; font-weight: 700; margin-bottom: 6px; }
.wf-node-items { display: flex; flex-direction: column; gap: 4px; font-size: 12px; color: var(--ls-text-muted); }
.wf-node-items li::before { content: '· '; }
.cap-phone { background: var(--ls-ink-panel); border: 1px solid var(--ls-line); border-radius: var(--ls-radius-phone); overflow: hidden; aspect-ratio: 9/19; display: flex; flex-direction: column; }
.phone-chrome { padding: 16px 16px 10px; background: var(--ls-ink); display: flex; align-items: center; justify-content: space-between; font-size: 11px; color: var(--ls-text-muted); }
.phone-content { flex: 1; overflow: hidden; }

/* ═══════════════════════════════════════
   § 3 UI LAB（暖白实验室）
═══════════════════════════════════════ */
.ui-lab { background: var(--ls-paper); color: var(--ls-ink); padding-block: clamp(60px,8vw,100px); border-top: 1px solid #d8d6cc; }
.ui-lab .cap-eyebrow { color: #535e63; }
.ui-lab .cap-title { color: var(--ls-ink); }
.lab-layout { display: grid; grid-template-columns: minmax(0,21fr) minmax(0,64fr) minmax(0,15fr); gap: 20px; align-items: start; margin-top: 40px; }
.lab-layout > * { min-width: 0; }
.lab-controls { background: #e8e6de; border-radius: 8px; padding: 20px; }
.lab-ctrl-section { margin-bottom: 24px; }
.lab-ctrl-section:last-child { margin-bottom: 0; }
.lab-ctrl-label { font: 700 11px/1.5 var(--ls-font-mono); letter-spacing: .14em; color: #535e63; margin-bottom: 10px; display: block; }
.lab-ctrl-options { display: flex; flex-direction: column; gap: 4px; }
.lab-ctrl-btn { display: flex; align-items: center; gap: 10px; padding: 10px 12px; border-radius: 6px; border: 1px solid transparent; background: transparent; font-size: 13px; color: #11171b; cursor: pointer; transition: background 140ms; width: 100%; text-align: left; }
.lab-ctrl-btn[aria-pressed=true] { background: #fff; border-color: #d6ff4d; }
.lab-ctrl-btn .ctrl-arrow { margin-left: auto; font-size: 10px; color: #535e63; }
.lab-ctrl-btn[aria-pressed=true] .ctrl-arrow { color: var(--ls-ink); }
.lab-density-track { display: flex; gap: 4px; }
.lab-density-btn { flex: 1; padding: 8px; border: 1px solid #d8d6cc; border-radius: 4px; background: transparent; font-size: 11px; color: #535e63; cursor: pointer; transition: all 140ms; text-align: center; }
.lab-density-btn[aria-pressed=true] { background: var(--ls-ink); color: var(--ls-lime); border-color: var(--ls-ink); }
.lab-preview { background: #fff; border-radius: 8px; overflow: hidden; border: 1px solid #d8d6cc; }
.lab-phone-mini { background: var(--ls-ink); border-radius: var(--ls-radius-phone); overflow: hidden; border: 1px solid var(--ls-line); aspect-ratio: 9/18; }
.device-toggle { display: flex; gap: 4px; margin-bottom: 12px; }
.device-btn { flex: 1; padding: 7px; border: 1px solid #d8d6cc; border-radius: 4px; background: transparent; font-size: 12px; font-weight: 600; color: #535e63; cursor: pointer; transition: all 140ms; }
.device-btn[aria-pressed=true] { background: var(--ls-ink); color: var(--ls-lime); border-color: var(--ls-ink); }
.lab-cta-row { text-align: center; margin-top: 32px; }

/* ─── footer ─── */
.site-footer { background: var(--ls-paper); color: var(--ls-ink); border-top: 1px solid #d8d6cc; padding: 40px var(--ls-page-gutter) 32px; }
.footer-inner { max-width: var(--ls-page-max); margin-inline: auto; display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 40px; }
.footer-brand-name { font-size: 16px; font-weight: 800; margin-bottom: 6px; }
.footer-brand-desc { font-size: 13px; color: #535e63; max-width: 24em; }
.footer-col h3 { font: 700 11px/1.5 var(--ls-font-mono); letter-spacing: .14em; color: #535e63; margin-bottom: 12px; }
.footer-col ul { display: flex; flex-direction: column; gap: 8px; }
.footer-col a { font-size: 14px; color: #11171b; transition: color 140ms; }
.footer-col a:hover { color: #305800; }
.footer-legal { max-width: var(--ls-page-max); margin-inline: auto; margin-top: 32px; padding-top: 20px; border-top: 1px solid #d8d6cc; display: flex; justify-content: space-between; align-items: center; font-size: 12px; color: #535e63; }

/* ─── page layout (service/lab/start pages) ─── */
.page-hero-dark { background: var(--ls-ink); padding-top: var(--ls-nav-height); padding-bottom: clamp(48px,7vw,88px); }
.page-hero-grid { display: grid; grid-template-columns: 1fr 1fr; gap: var(--ls-grid-gap); align-items: center; }
.page-title { font-family: var(--ls-font-display); font-size: clamp(2.4rem,5.5vw,5.5rem); font-weight: 800; letter-spacing: -.05em; line-height: 1.05; }
.page-lead { font-size: clamp(15px,1.3vw,17px); line-height: 1.75; color: var(--ls-text-muted); margin: 20px 0 32px; max-width: 30em; }
.page-section-warm { background: var(--ls-paper); color: var(--ls-ink); padding-block: clamp(48px,6vw,80px); border-top: 1px solid #d8d6cc; }
.page-section-dark { background: var(--ls-ink); padding-block: clamp(48px,6vw,80px); border-top: 1px solid var(--ls-line); }
.section-eyebrow { font: 500 11px/1.5 var(--ls-font-mono); letter-spacing: .16em; color: var(--ls-text-muted); margin-bottom: 12px; }
.section-title { font-family: var(--ls-font-display); font-size: clamp(1.8rem,3.5vw,3.5rem); font-weight: 800; letter-spacing: -.04em; line-height: 1.1; margin-bottom: 32px; }
.section-title-warm { color: var(--ls-ink); }
.deliverables-list { display: flex; flex-direction: column; gap: 1px; }
.deliverable-item { display: grid; grid-template-columns: 40px 1fr; gap: 16px; padding: 20px 0; border-top: 1px solid var(--ls-line); align-items: start; }
.deliverable-item.warm { border-color: #d8d6cc; }
.deliverable-no { font: 700 11px/1.5 var(--ls-font-mono); letter-spacing: .12em; color: var(--ls-lime); padding-top: 2px; }
.deliverable-no.dark-lime { color: #305800; }
.deliverable-name { font-size: 16px; font-weight: 700; margin-bottom: 4px; }
.deliverable-desc { font-size: 14px; color: var(--ls-text-muted); }
.deliverable-desc.warm { color: #535e63; }
.process-steps { display: grid; grid-template-columns: repeat(4,1fr); gap: 24px; }
.process-step { padding: 24px 0; border-top: 2px solid var(--ls-line); }
.process-step.warm { border-color: #d8d6cc; }
.process-step-no { font: 700 11px/1.5 var(--ls-font-mono); letter-spacing: .14em; color: var(--ls-lime); margin-bottom: 10px; }
.process-step-no.dark-lime { color: #305800; }
.process-step-title { font-size: 17px; font-weight: 700; margin-bottom: 8px; }
.process-step-desc { font-size: 14px; color: var(--ls-text-muted); }
.process-step-desc.warm { color: #535e63; }
.faq-list { display: flex; flex-direction: column; gap: 1px; }
details.faq-item { border-top: 1px solid var(--ls-line); }
details.faq-item.warm { border-color: #d8d6cc; }
details.faq-item summary { display: flex; align-items: center; justify-content: space-between; padding: 18px 0; font-size: 16px; font-weight: 600; cursor: pointer; list-style: none; gap: 16px; }
details.faq-item summary::-webkit-details-marker { display: none; }
details.faq-item summary::after { content: '+'; font-size: 20px; color: var(--ls-text-muted); flex-shrink: 0; transition: transform 160ms; }
details.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-answer { padding: 0 0 18px; font-size: 15px; color: var(--ls-text-muted); line-height: 1.75; max-width: 52em; }
.faq-answer.warm { color: #535e63; }

/* ─── workflow node graph (agents page) ─── */
.node-graph { display: grid; grid-template-columns: repeat(4,1fr); gap: 16px; padding: 32px; background: var(--ls-ink-panel); border-radius: var(--ls-radius-panel); border: 1px solid var(--ls-line); }
.node-box { border: 1px solid var(--ls-line); border-radius: 6px; padding: 20px; background: var(--ls-ink); cursor: pointer; transition: border-color 200ms; }
.node-box:hover, .node-box[aria-expanded=true] { border-color: var(--ls-cyan); }
.node-box-head { display: flex; align-items: center; gap: 10px; margin-bottom: 10px; }
.node-icon { width: 28px; height: 28px; border-radius: 4px; background: rgba(73,215,243,.12); display: grid; place-items: center; }
.node-icon svg { width: 14px; height: 14px; stroke: var(--ls-cyan); stroke-width: 1.5; fill: none; }
.node-title { font-size: 13px; font-weight: 700; }
.node-detail { font-size: 12px; color: var(--ls-text-muted); line-height: 1.6; display: none; }
.node-box[aria-expanded=true] .node-detail { display: block; }

/* ─── software table ─── */
.sw-table-wrap { overflow-x: auto; }
table.sw-table { width: 100%; border-collapse: collapse; font-size: 14px; }
.sw-table th { padding: 12px 16px; border-bottom: 2px solid #d8d6cc; text-align: left; font-size: 12px; font-weight: 700; letter-spacing: .06em; color: #535e63; white-space: nowrap; }
.sw-table td { padding: 14px 16px; border-bottom: 1px solid #d8d6cc; }
.sw-table tr:hover td { background: #ebe9e0; }
.status-badge { display: inline-flex; align-items: center; gap: 5px; padding: 3px 10px; border-radius: 20px; font-size: 11px; font-weight: 700; }
.status-running { background: rgba(73,215,243,.15); color: #0a6a7a; }
.status-done { background: rgba(145,231,176,.15); color: #126132; }
.status-pending { background: rgba(214,255,77,.15); color: #4a6200; }

/* ─── lab page ─── */
.lab-page { min-height: 100vh; background: var(--ls-paper); padding-top: var(--ls-nav-height); }
.lab-page-layout { display: grid; grid-template-columns: 280px 1fr; min-height: calc(100vh - var(--ls-nav-height)); }
.lab-sidebar { background: #e8e6de; border-right: 1px solid #d8d6cc; padding: 32px 24px; overflow-y: auto; position: sticky; top: var(--ls-nav-height); height: calc(100vh - var(--ls-nav-height)); }
.lab-main { padding: 40px; overflow-y: auto; }
.lab-sidebar-section { margin-bottom: 28px; }
.lab-sidebar-title { font: 700 10px/1.5 var(--ls-font-mono); letter-spacing: .16em; color: #535e63; margin-bottom: 10px; }
.lab-tab-list { display: flex; gap: 4px; flex-wrap: wrap; margin-bottom: 28px; }
.lab-tab { padding: 8px 14px; border-radius: 4px; border: 1px solid #d8d6cc; background: transparent; font-size: 12px; font-weight: 600; color: #535e63; cursor: pointer; transition: all 140ms; }
.lab-tab[aria-selected=true] { background: var(--ls-ink); color: var(--ls-lime); border-color: var(--ls-ink); }

/* ─── start page ─── */
.start-page { min-height: 100vh; background: var(--ls-ink); padding-top: var(--ls-nav-height); }
.start-layout { display: grid; grid-template-columns: minmax(0,58fr) minmax(0,42fr); gap: 40px; align-items: start; padding-block: 48px; }
.start-layout > * { min-width: 0; }
.start-steps { display: flex; gap: 0; margin-bottom: 32px; }
.start-step { flex: 1; padding: 12px 16px; border-bottom: 2px solid var(--ls-line); font-size: 13px; color: var(--ls-text-muted); cursor: pointer; transition: border-color 160ms, color 160ms; background: transparent; border-top: none; border-left: none; border-right: none; text-align: left; }
.start-step[aria-current=step] { border-color: var(--ls-lime); color: var(--ls-text); font-weight: 700; }
.start-card { background: var(--ls-ink-panel); border: 1px solid var(--ls-line); border-radius: var(--ls-radius-panel); padding: 24px; position: sticky; top: calc(var(--ls-nav-height) + 24px); }
.brief-label { font: 500 11px/1.5 var(--ls-font-mono); letter-spacing: .14em; color: var(--ls-text-muted); margin-bottom: 6px; }
.brief-value { font-size: 14px; margin-bottom: 16px; color: var(--ls-text); min-height: 1.4em; }
.option-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; margin-bottom: 24px; }
.option-btn { padding: 16px; border: 1px solid var(--ls-line); border-radius: 6px; background: var(--ls-ink); color: var(--ls-text); font-size: 14px; font-weight: 600; cursor: pointer; text-align: left; transition: all 160ms; }
.option-btn[aria-pressed=true] { border-color: var(--ls-lime); background: rgba(214,255,77,.06); }
.option-btn-label { font-size: 10px; font-weight: 500; letter-spacing: .12em; color: var(--ls-text-muted); margin-bottom: 4px; font-family: var(--ls-font-mono); }
textarea.brief-textarea { width: 100%; min-height: 100px; padding: 12px; border: 1px solid var(--ls-line); border-radius: 4px; background: var(--ls-ink-panel); color: var(--ls-text); font: 14px/1.6 var(--ls-font-ui); resize: vertical; margin-bottom: 16px; }
textarea.brief-textarea:focus { outline: 3px solid var(--ls-focus); }
.field-error { font-size: 12px; color: var(--ls-error); margin-top: -12px; margin-bottom: 12px; display: none; }
.field-error[aria-live] { }

/* ─── privacy / 404 ─── */
.prose-page { background: var(--ls-paper); color: var(--ls-ink); min-height: 100vh; padding-top: var(--ls-nav-height); }
.prose-inner { max-width: 760px; margin-inline: auto; padding: 64px var(--ls-page-gutter); }
.prose-inner h1 { font-size: clamp(2rem,4vw,3rem); font-weight: 800; letter-spacing: -.04em; margin-bottom: 32px; }
.prose-inner h2 { font-size: 1.25rem; font-weight: 700; margin: 32px 0 10px; }
.prose-inner p, .prose-inner li { font-size: 15px; line-height: 1.8; color: #11171b; margin-bottom: 12px; }
.prose-inner ul { padding-left: 20px; list-style: disc; }
.page-404-center { display: flex; flex-direction: column; align-items: center; justify-content: center; min-height: calc(100vh - var(--ls-nav-height)); text-align: center; padding: 40px; }
.page-404-code { font: 900 clamp(96px,18vw,200px)/.9 var(--ls-font-display); color: var(--ls-lime); margin-bottom: 24px; letter-spacing: -.08em; }
.page-404-msg { font-size: 20px; color: var(--ls-text-muted); margin-bottom: 32px; }

/* ─── responsive ─── */
@media (max-width: 1199px) {
  .hero-stage { grid-template-columns: 48fr 52fr; }
  .lab-layout { grid-template-columns: minmax(0,24fr) minmax(0,60fr) minmax(0,16fr); }
  .process-steps { grid-template-columns: 1fr 1fr; }
  .footer-inner { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 767px) {
  .hero-stage { grid-template-columns: 1fr; gap: 32px; }
  .hero-canvas-wrap { aspect-ratio: 1/0.8; }
  .hero-layers { top: auto; bottom: 8px; right: 4px; transform: none; flex-direction: row; gap: 6px; }
  .hero-layer-btn { padding: 4px 8px; font-size: 9px; }
  .service-tabs { grid-template-columns: 1fr 1fr; }
  .scroll-hint { display: none; }
  .cap-head { grid-template-columns: 1fr; }
  .cap-body { grid-template-columns: 1fr; }
  .workflow-nodes { grid-template-columns: 1fr 1fr; }
  .wf-connector { display: none; }
  .lab-layout { grid-template-columns: 1fr; }
  .lab-phone-mini { display: none; }
  .page-hero-grid { grid-template-columns: 1fr; }
  .nav-links { display: none; }
  .nav-menu-btn { display: inline-flex; }
  .start-layout { grid-template-columns: 1fr; }
  .start-card { position: static; }
  .option-grid { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr; }
  .lab-page-layout { grid-template-columns: 1fr; }
  .lab-sidebar { position: static; height: auto; }
  .node-graph { grid-template-columns: 1fr 1fr; }
  .process-steps { grid-template-columns: 1fr; }
}
@media (max-width: 389px) {
  .hero-title { font-size: 2.75rem; }
  .service-tabs { grid-template-columns: 1fr 1fr; }
  .workflow-nodes { grid-template-columns: 1fr; }
}
html[data-motion=reduced] *, html[data-motion=reduced] *::before, html[data-motion=reduced] *::after { animation: none !important; transition-duration: 0ms !important; }

@media(max-width:389px){
  .start-page .start-steps{display:grid;grid-template-columns:repeat(2,minmax(0,1fr))}
  .start-page .start-step{white-space:nowrap;padding:12px 8px;min-height:44px}
}
.prose-inner :focus-visible{outline-color:#285b00}

/* Keep the shared navigation comfortable with the desktop download entry. */
.nav-links a, .nav-brand, .nav-cta { white-space: nowrap; }
@media (min-width: 768px) and (max-width: 999px) {
  .nav-links { gap: 18px; font-size: 13px; }
}