/* Seamline · AI operations, seamlessly human. */
:root {
  --ink: #0F172A;
  --ink-soft: #334155;
  --muted: #475569;
  --line: #E2E8F0;
  --bg: #F8FAFC;
  --surface: #FFFFFF;
  --indigo: #4F46E5;
  --indigo-dark: #4338CA;
  --indigo-tint: #EEF2FF;
  --teal: #14B8A6;
  --teal-dark: #0F766E;
  --teal-tint: #F0FDFA;
  --radius: 14px;
  --max: 1120px;
  --font: "Sora", system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.6;
  color: var(--ink-soft);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

img, svg { display: block; max-width: 100%; }
h1, h2, h3 { color: var(--ink); line-height: 1.15; margin: 0 0 16px; font-weight: 600; letter-spacing: -0.02em; }
h1 { font-size: clamp(2.2rem, 5vw, 3.6rem); }
h2 { font-size: clamp(1.7rem, 3.4vw, 2.4rem); }
h3 { font-size: 1.15rem; letter-spacing: -0.01em; }
p { margin: 0 0 16px; }
a { color: var(--indigo-dark); }
a:hover { color: var(--ink); }

:focus-visible { outline: 3px solid var(--indigo); outline-offset: 3px; border-radius: 6px; }

.skip-link {
  position: absolute; left: 16px; top: -60px; z-index: 100;
  background: var(--ink); color: #fff; padding: 10px 16px; border-radius: 8px; text-decoration: none;
}
.skip-link:focus { top: 16px; color: #fff; }

.container { width: 100%; max-width: var(--max); margin: 0 auto; padding: 0 20px; }

/* Header */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(248, 250, 252, 0.92);
  backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 72px; flex-wrap: wrap; }
.brand { display: inline-flex; align-items: center; gap: 10px; text-decoration: none; color: var(--ink); }
.brand svg { width: 40px; height: 24px; }
.brand span { font-size: 1.45rem; font-weight: 600; letter-spacing: -0.04em; }
.nav { display: flex; align-items: center; gap: 24px; flex-wrap: wrap; }
.nav a { text-decoration: none; color: var(--ink-soft); font-size: 0.95rem; }
.nav a:hover { color: var(--ink); }
.nav .btn { color: #fff; }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 48px; padding: 12px 22px; border-radius: 999px;
  font-family: inherit; font-size: 1rem; font-weight: 600; text-decoration: none;
  border: 2px solid transparent; transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}
.btn-primary { background: var(--indigo); color: #fff; }
.btn-primary:hover { background: var(--indigo-dark); color: #fff; }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--line); }
.btn-ghost:hover { border-color: var(--ink); color: var(--ink); }
.btn-light { background: #fff; color: var(--ink); }
.btn-light:hover { background: var(--indigo-tint); color: var(--ink); }
.btn-outline-light { background: transparent; color: #fff; border-color: rgba(255,255,255,0.5); }
.btn-outline-light:hover { border-color: #fff; color: #fff; }

/* Sections */
section { padding: 88px 0; }
.eyebrow {
  display: inline-block; font-size: 0.8rem; font-weight: 600; letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--teal-dark); margin-bottom: 14px;
}
.lead { font-size: 1.15rem; color: var(--muted); max-width: 640px; }
.section-head { max-width: 720px; margin-bottom: 48px; }

/* Hero */
.hero { padding: 96px 0 88px; position: relative; overflow: hidden; }
.hero-grid { display: grid; grid-template-columns: 1.15fr 0.85fr; gap: 48px; align-items: center; }
.hero h1 span { color: var(--indigo); }
.hero .lead { margin-bottom: 32px; }
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }
.hero-note { margin-top: 20px; font-size: 0.9rem; color: var(--muted); }
.hero-visual {
  background: var(--surface); border: 1px solid var(--line); border-radius: 24px; padding: 32px;
  box-shadow: 0 24px 60px -30px rgba(15, 23, 42, 0.25);
}
.flow { display: grid; gap: 14px; }
.flow-row { display: flex; align-items: center; gap: 14px; padding: 14px 16px; border-radius: 12px; background: var(--bg); border: 1px solid var(--line); }
.flow-row .dot { width: 12px; height: 12px; border-radius: 50%; flex: 0 0 auto; }
.dot-ai { background: var(--indigo); }
.dot-human { background: var(--teal); }
.flow-row strong { color: var(--ink); font-weight: 600; display: block; font-size: 0.98rem; }
.flow-row small { color: var(--muted); font-size: 0.85rem; }
.flow-row.ai { background: var(--indigo-tint); border-color: #C7D2FE; }
.flow-row.human { background: var(--teal-tint); border-color: #99F6E4; }
.flow-merge { display: flex; justify-content: center; }
.flow-merge svg { width: 120px; height: 72px; }

/* Problem */
.problem { background: var(--surface); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.cards-4 { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 20px; }
.card {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px;
}
.problem .card { background: var(--bg); }
.card p { margin: 0; color: var(--muted); font-size: 0.97rem; }

/* Services */
.services-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; }
.service { display: flex; flex-direction: column; gap: 10px; }
.service .icon {
  width: 44px; height: 44px; border-radius: 12px; display: grid; place-items: center;
  background: var(--indigo-tint); color: var(--indigo); margin-bottom: 6px;
}
.service .icon svg { width: 22px; height: 22px; }
.service.featured { border-color: var(--indigo); box-shadow: 0 0 0 1px var(--indigo) inset; }
.tag {
  align-self: flex-start; font-size: 0.75rem; font-weight: 600; padding: 4px 10px; border-radius: 999px;
  background: var(--indigo); color: #fff;
}
.service ul { margin: 4px 0 0; padding-left: 18px; color: var(--muted); font-size: 0.95rem; }
.service li { margin-bottom: 4px; }

/* How it works */
.how { background: var(--surface); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.steps { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; counter-reset: step; list-style: none; padding: 0; margin: 0; }
.step { position: relative; padding-top: 64px; }
.step::before {
  counter-increment: step; content: counter(step);
  position: absolute; top: 24px; left: 24px; width: 32px; height: 32px; border-radius: 50%;
  display: grid; place-items: center; background: var(--ink); color: #fff; font-weight: 600; font-size: 0.9rem;
}
.step .label { font-size: 0.8rem; font-weight: 600; color: var(--teal-dark); text-transform: uppercase; letter-spacing: 0.06em; margin-bottom: 6px; }
.how-note { margin-top: 28px; color: var(--muted); font-size: 0.95rem; }

/* Why */
.why-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; }
.why-item h3 { display: flex; align-items: center; gap: 10px; }
.why-item h3::before { content: ""; width: 10px; height: 10px; border-radius: 50%; background: var(--teal); flex: 0 0 auto; }

/* FAQ */
.faq { background: var(--surface); border-top: 1px solid var(--line); }
.faq-list { max-width: 820px; display: grid; gap: 12px; }
details { background: var(--bg); border: 1px solid var(--line); border-radius: 12px; padding: 0 20px; }
summary {
  cursor: pointer; list-style: none; padding: 18px 32px 18px 0; position: relative;
  font-weight: 600; color: var(--ink); min-height: 44px;
}
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; position: absolute; right: 0; top: 14px; font-size: 1.5rem; color: var(--indigo); line-height: 1.2; }
details[open] summary::after { content: "\2212"; }
details p { color: var(--muted); padding-bottom: 18px; margin: 0; }

/* CTA band */
.cta-band { background: var(--ink); color: #CBD5E1; padding: 80px 0; }
.cta-band h2 { color: #fff; }
.cta-inner { display: flex; align-items: center; justify-content: space-between; gap: 32px; flex-wrap: wrap; }
.cta-inner p { max-width: 560px; margin: 0; }
.cta-actions { display: flex; gap: 12px; flex-wrap: wrap; }

/* Footer */
.site-footer { background: var(--ink); color: #94A3B8; border-top: 1px solid #1E293B; padding: 32px 0; font-size: 0.9rem; }
.footer-inner { display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
.site-footer a { color: #CBD5E1; text-decoration: none; }
.site-footer a:hover { color: #fff; text-decoration: underline; }
.footer-links { display: flex; gap: 20px; flex-wrap: wrap; }
.footer-brand { display: inline-flex; align-items: center; gap: 10px; color: #fff; font-weight: 600; letter-spacing: -0.03em; font-size: 1.1rem; }
.footer-brand svg { width: 32px; height: 20px; }

/* Legal pages */
.legal { padding: 64px 0 88px; }
.legal .container { max-width: 820px; }
.legal h1 { font-size: clamp(2rem, 4vw, 2.6rem); }
.legal h2 { font-size: 1.3rem; margin-top: 36px; }
.legal ul { padding-left: 20px; }
.placeholder { background: #FEF9C3; color: var(--ink); padding: 0 4px; border-radius: 4px; }
.notice { background: var(--indigo-tint); border: 1px solid #C7D2FE; border-radius: 12px; padding: 16px 20px; color: var(--ink); margin-bottom: 32px; font-size: 0.95rem; }

/* Responsive */
@media (max-width: 960px) {
  .hero-grid { grid-template-columns: 1fr; }
  .cards-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .services-grid, .why-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .steps { grid-template-columns: 1fr; }
}
@media (max-width: 640px) {
  body { font-size: 16px; }
  section { padding: 64px 0; }
  .hero { padding: 56px 0 64px; }
  .nav a:not(.btn) { display: none; }
  .cards-4, .services-grid, .why-grid { grid-template-columns: 1fr; }
  .hero-visual { padding: 20px; }
  .btn { width: 100%; }
  .nav .btn { width: auto; min-height: 40px; padding: 8px 14px; font-size: 0.85rem; }
  .header-inner { flex-wrap: nowrap; min-height: 64px; }
  .brand span { font-size: 1.25rem; }
  .brand svg { width: 34px; height: 20px; }
  .hero-actions, .cta-actions { flex-direction: column; width: 100%; }
}

/* ===== Tech layer: dark hero, AI console, request flow, scroll effects ===== */
:root {
  --night: #070B18;
  --night-2: #0B1120;
  --night-card: rgba(30, 41, 59, 0.55);
  --night-line: rgba(148, 163, 184, 0.16);
  --on-night: #CBD5E1;
  --on-night-muted: #94A3B8;
  --indigo-light: #A5B4FC;
  --teal-light: #5EEAD4;
}

/* Scroll progress bar (browsers with scroll-driven animations) */
.progress {
  position: fixed; top: 0; left: 0; z-index: 60; height: 3px; width: 100%;
  transform-origin: 0 50%; transform: scaleX(0);
  background: linear-gradient(90deg, var(--indigo), var(--teal));
}
@supports (animation-timeline: scroll()) {
  .progress { animation: grow-x linear both; animation-timeline: scroll(root); }
}
@keyframes grow-x { to { transform: scaleX(1); } }

/* Dark header */
.site-header { background: rgba(7, 11, 24, 0.82); border-bottom-color: var(--night-line); }
.brand { color: #fff; }
.nav a { color: var(--on-night); }
.nav a:hover { color: #fff; }

/* Hero */
.hero { background: var(--night); color: var(--on-night); padding: 96px 0 56px; }
.hero-bg {
  position: absolute; inset: 0; pointer-events: none;
  background-image:
    radial-gradient(620px 420px at 82% 18%, rgba(79, 70, 229, 0.30), transparent 62%),
    radial-gradient(520px 380px at 8% 92%, rgba(20, 184, 166, 0.18), transparent 60%),
    radial-gradient(rgba(148, 163, 184, 0.16) 1px, transparent 1px);
  background-size: auto, auto, 26px 26px;
  -webkit-mask-image: linear-gradient(to bottom, #000 70%, transparent);
          mask-image: linear-gradient(to bottom, #000 70%, transparent);
  animation: grid-drift 60s linear infinite;
}
@keyframes grid-drift { to { background-position: 0 0, 0 0, 260px 520px; } }
.hero-grid { position: relative; z-index: 1; grid-template-columns: 1.05fr 0.95fr; }
.hero h1 { color: #fff; }
.hero h1 span { color: var(--teal-light); }
.hero .lead { color: var(--on-night); }
.hero-note { color: var(--on-night-muted); }
.eyebrow-dark { color: var(--teal-light); display: inline-flex; align-items: center; gap: 10px; }
.pulse { position: relative; width: 8px; height: 8px; border-radius: 50%; background: var(--teal-light); }
.pulse::after { content: ""; position: absolute; inset: -4px; border-radius: 50%; border: 2px solid var(--teal-light); animation: ping 2s ease-out infinite; }
@keyframes ping { 0% { transform: scale(0.6); opacity: 0.9; } 100% { transform: scale(2.2); opacity: 0; } }
.hero .btn-ghost { color: #fff; border-color: rgba(255, 255, 255, 0.28); }
.hero .btn-ghost:hover { border-color: #fff; color: #fff; }

/* AI console */
.console-wrap { margin: 0; min-width: 0; }
.console {
  position: relative; overflow: hidden; border-radius: 18px;
  background: rgba(15, 23, 42, 0.88); border: 1px solid rgba(148, 163, 184, 0.22);
  box-shadow: 0 40px 90px -40px rgba(79, 70, 229, 0.65), 0 0 0 1px rgba(129, 140, 248, 0.08) inset;
}
.console-bar { display: flex; align-items: center; gap: 12px; padding: 12px 16px; border-bottom: 1px solid var(--night-line); }
.win-dots { display: inline-flex; gap: 6px; }
.win-dots i { width: 10px; height: 10px; border-radius: 50%; background: rgba(148, 163, 184, 0.35); }
.console-title { color: #E2E8F0; font-size: 0.85rem; font-weight: 600; }
.live { margin-left: auto; display: inline-flex; align-items: center; gap: 6px; font-size: 0.72rem; font-weight: 600; letter-spacing: 0.06em; text-transform: uppercase; color: var(--teal-light); }
.live-dot { width: 7px; height: 7px; border-radius: 50%; background: var(--teal-light); animation: blink 1.6s ease-in-out infinite; }
@keyframes blink { 50% { opacity: 0.25; } }
.console-body { position: relative; padding: 14px; }
.scan {
  position: absolute; left: 0; right: 0; top: 0; height: 70px; pointer-events: none;
  background: linear-gradient(to bottom, transparent, rgba(129, 140, 248, 0.14), transparent);
  animation: scan 4.5s linear infinite;
}
@keyframes scan { from { transform: translateY(-70px); } to { transform: translateY(360px); } }
.queue { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; position: relative; }
.req {
  display: grid; grid-template-columns: auto minmax(0, 1fr) auto; align-items: center; gap: 12px;
  padding: 12px; border-radius: 12px; background: rgba(30, 41, 59, 0.6); border: 1px solid rgba(148, 163, 184, 0.12);
}
.ch { font-size: 0.66rem; font-weight: 600; text-transform: uppercase; letter-spacing: 0.06em; color: var(--on-night-muted); border: 1px solid rgba(148, 163, 184, 0.28); border-radius: 6px; padding: 2px 6px; }
.req-main { min-width: 0; }
.req-main strong { display: block; color: #F1F5F9; font-size: 0.88rem; font-weight: 600; line-height: 1.35; }
.req-main small { color: var(--on-night-muted); font-size: 0.76rem; }
.status { display: grid; justify-items: end; min-width: 140px; }
.st { grid-area: 1 / 1; font-size: 0.72rem; font-weight: 600; padding: 4px 10px; border-radius: 999px; white-space: nowrap; display: inline-flex; align-items: center; gap: 6px; }
.st-work { background: rgba(148, 163, 184, 0.14); color: var(--on-night); animation: st-work 9s ease infinite both; }
.st-done { animation: st-done 9s ease infinite both; }
.st-ai { background: rgba(79, 70, 229, 0.28); color: #E0E7FF; border: 1px solid rgba(129, 140, 248, 0.55); }
.st-human { background: rgba(20, 184, 166, 0.18); color: #CCFBF1; border: 1px solid rgba(45, 212, 191, 0.55); }
.r2 .st { animation-delay: 0.8s; }
.r3 .st { animation-delay: 1.6s; }
.r4 .st { animation-delay: 2.4s; }
@keyframes st-work { 0%, 32% { opacity: 1; } 36%, 100% { opacity: 0; } }
@keyframes st-done { 0%, 32% { opacity: 0; transform: scale(0.88); } 38%, 96% { opacity: 1; transform: none; } 100% { opacity: 0; } }
.typing { display: inline-flex; gap: 3px; }
.typing i { width: 4px; height: 4px; border-radius: 50%; background: currentColor; animation: typing 1s ease-in-out infinite; }
.typing i:nth-child(2) { animation-delay: 0.15s; }
.typing i:nth-child(3) { animation-delay: 0.3s; }
@keyframes typing { 0%, 100% { opacity: 0.25; transform: translateY(0); } 50% { opacity: 1; transform: translateY(-2px); } }
.console-foot { display: flex; flex-wrap: wrap; gap: 8px 16px; padding: 10px 16px; border-top: 1px solid var(--night-line); font-size: 0.72rem; color: var(--on-night-muted); }
.console-foot span::before { content: ""; display: inline-block; width: 6px; height: 6px; border-radius: 50%; background: var(--indigo-light); margin-right: 6px; vertical-align: middle; }
.console-caption { margin-top: 10px; font-size: 0.75rem; color: var(--on-night-muted); text-align: right; }

/* Scroll cue */
.cue-wrap { position: relative; z-index: 1; text-align: center; margin-top: 48px; }
.scroll-cue { display: inline-flex; align-items: center; gap: 8px; color: var(--on-night-muted); text-decoration: none; font-size: 0.88rem; }
.scroll-cue:hover { color: #fff; }
.cue-arrow { display: inline-block; animation: bob 1.8s ease-in-out infinite; }
@keyframes bob { 50% { transform: translateY(5px); } }

/* Request flow */
.flow-section { background: var(--night-2); color: var(--on-night); border-top: 1px solid var(--night-line); }
.flow-section h2, .flow-section h3 { color: #fff; }
.flow-section .lead { color: var(--on-night); }
.pipeline { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 24px; }
.pipe-step {
  position: relative; padding: 24px; border-radius: 16px; background: var(--night-card); border: 1px solid var(--night-line);
  animation: step-glow 6s ease infinite;
}
.pipe-step:nth-child(2) { animation-delay: 1.5s; }
.pipe-step:nth-child(3) { animation-delay: 3s; }
.pipe-step:nth-child(4) { animation-delay: 4.5s; }
@keyframes step-glow {
  0%, 22% { border-color: rgba(129, 140, 248, 0.8); box-shadow: 0 0 0 1px rgba(129, 140, 248, 0.45), 0 24px 50px -28px rgba(79, 70, 229, 0.9); }
  32%, 100% { border-color: var(--night-line); box-shadow: none; }
}
.pipe-step p { margin: 0; color: var(--on-night-muted); font-size: 0.95rem; }
.pipe-no { display: inline-block; margin-bottom: 14px; font-size: 0.8rem; font-weight: 600; letter-spacing: 0.12em; color: var(--teal-light); font-variant-numeric: tabular-nums; }
.pipe-step:not(:last-child)::after {
  content: ""; position: absolute; top: 50%; right: -24px; width: 24px; height: 2px;
  background: linear-gradient(90deg, var(--indigo-light) 0 50%, transparent 50%) 0 0 / 8px 2px repeat-x;
  animation: dash-x 0.8s linear infinite;
}
@keyframes dash-x { to { background-position: 8px 0; } }

/* Interaction polish */
.card { transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease; }
.card:hover { transform: translateY(-3px); box-shadow: 0 18px 40px -24px rgba(15, 23, 42, 0.35); }

/* Reveal on scroll (browsers with view timelines) */
@supports (animation-timeline: view()) {
  @media (prefers-reduced-motion: no-preference) {
    .section-head, .card:not(.pipe-step) { animation: reveal linear both; animation-timeline: view(); animation-range: entry 0% entry 45%; }
  }
}
@keyframes reveal { from { opacity: 0.3; transform: translateY(28px); } to { opacity: 1; transform: none; } }

/* Responsive for the tech layer */
@media (max-width: 960px) {
  .hero-grid { grid-template-columns: 1fr; }
  .pipeline { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .pipe-step:nth-child(2)::after { display: none; }
}
@media (max-width: 640px) {
  .hero { padding: 56px 0 40px; }
  .req { grid-template-columns: auto minmax(0, 1fr); }
  .status { grid-column: 1 / -1; justify-items: start; min-width: 0; }
  .pipeline { grid-template-columns: 1fr; gap: 20px; }
  .pipe-step:not(:last-child)::after {
    display: block; top: auto; bottom: -20px; right: auto; left: 36px; width: 2px; height: 20px;
    background: linear-gradient(180deg, var(--indigo-light) 0 50%, transparent 50%) 0 0 / 2px 8px repeat-y;
    animation-name: dash-y;
  }
  .console-caption { text-align: left; }
}
@keyframes dash-y { to { background-position: 0 8px; } }

/* Reduced motion: show final states, stop loops */
@media (prefers-reduced-motion: reduce) {
  .hero-bg, .pulse::after, .live-dot, .scan, .typing i, .cue-arrow, .pipe-step, .pipe-step::after { animation: none !important; }
  .scan { display: none; }
  .st-work { display: none; }
  .st-done { animation: none; opacity: 1; }
  .card:hover { transform: none; }
}

/* ===== Intro: particle logo ===== */
.intro {
  position: relative; display: grid; place-items: center; overflow: hidden; padding: 0;
  min-height: calc(100svh - 72px);
  background: radial-gradient(560px 440px at 50% 50%, rgba(56, 72, 150, 0.32), transparent 70%), #06080F;
  color: #fff;
}
#intro-canvas { position: absolute; inset: 0; width: 100%; height: 100%; display: block; }
.intro-words {
  position: relative; z-index: 1; width: 100%; display: grid; align-items: center;
  grid-template-columns: minmax(0, 1fr) var(--mark-w, 34vw) minmax(0, 1fr); column-gap: 32px; pointer-events: none;
  opacity: calc(1 - var(--sp, 0) * 1.3);
}
.intro-word { font-size: clamp(3rem, 7.5vw, 7.5rem); font-weight: 400; letter-spacing: -0.045em; line-height: 1; color: #fff; }
.intro-word-ai { justify-self: end; transform: translateX(calc(var(--sp, 0) * -120px)); }
.intro-word-human { justify-self: start; transform: translateX(calc(var(--sp, 0) * 120px)); }
.intro-fallback { visibility: hidden; width: 100%; height: auto; }
.intro:not(.has-particles) .intro-words { grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr); }
.intro:not(.has-particles) .intro-fallback { visibility: visible; width: 30vw; max-width: 420px; }
.intro-tag { position: absolute; left: 0; right: 0; bottom: 104px; z-index: 1; margin: 0; text-align: center; color: var(--on-night-muted); font-size: 0.95rem; letter-spacing: 0.02em; padding: 0 20px; }
.mouse { position: absolute; bottom: 40px; left: 50%; z-index: 1; width: 26px; height: 40px; margin-left: -13px; border: 2px solid rgba(203, 213, 225, 0.7); border-radius: 14px; }
.mouse span { position: absolute; top: 7px; left: 50%; width: 3px; height: 7px; margin-left: -1.5px; border-radius: 2px; background: #CBD5E1; animation: wheel 1.6s ease-in-out infinite; }
.mouse:hover { border-color: #fff; }
@keyframes wheel { 0% { transform: translateY(0); opacity: 1; } 80% { transform: translateY(10px); opacity: 0; } 100% { opacity: 0; } }
@media (max-width: 640px) {
  .intro-words { grid-template-columns: 1fr; grid-template-rows: auto var(--mark-h, 40vw) auto; row-gap: 16px; justify-items: center; }
  .intro-word-ai, .intro-word-human { justify-self: center; }
  .intro-word { font-size: clamp(2.6rem, 14vw, 4rem); }
  .intro-word-ai, .intro-word-human { justify-self: center; transform: none; }
  .intro.has-particles .intro-fallback { height: var(--mark-h, 40vw); }
  .intro:not(.has-particles) .intro-fallback { width: 70vw; }
}
@media (prefers-reduced-motion: reduce) {
  .mouse span { animation: none; }
}

/* ===== Header: brand in focus ===== */
.site-header { background: rgba(7, 11, 24, 0.94); border-bottom-color: transparent; transition: background 0.35s ease, backdrop-filter 0.35s ease; }
.site-header::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -1px; height: 1px; pointer-events: none;
  background: linear-gradient(90deg, transparent, rgba(129, 140, 248, 0.65), rgba(45, 212, 191, 0.65), transparent);
  transition: opacity 0.35s ease;
}
body.at-intro .site-header { background: transparent; -webkit-backdrop-filter: none; backdrop-filter: none; }
body.at-intro .site-header::after { opacity: 0; }
.intro { margin-top: -72px; padding-top: 72px; min-height: 100svh; }
.brand { gap: 12px; }
.brand .brand-mark {
  width: 50px; height: 30px; overflow: visible;
  filter: drop-shadow(0 0 6px rgba(129, 140, 248, 0.55)) drop-shadow(0 0 12px rgba(45, 212, 191, 0.35));
  transition: filter 0.25s ease, transform 0.25s ease;
}
.brand:hover .brand-mark { transform: translateX(2px); filter: drop-shadow(0 0 8px rgba(129, 140, 248, 0.8)) drop-shadow(0 0 16px rgba(45, 212, 191, 0.55)); }
.brand span { font-size: 1.6rem; letter-spacing: -0.045em; }
.brand-flow path { stroke-dasharray: 14 100; stroke-dashoffset: 14; opacity: 0.9; animation: brand-flow 3.6s ease-in-out infinite; }
.brand-flow path:nth-child(2) { animation-delay: 0.45s; }
@keyframes brand-flow { 0% { stroke-dashoffset: 14; } 55%, 100% { stroke-dashoffset: -100; } }
@media (max-width: 640px) {
  .intro { margin-top: -64px; padding-top: 64px; }
  .brand .brand-mark { width: 40px; height: 24px; }
  .brand span { font-size: 1.3rem; }
}
@media (prefers-reduced-motion: reduce) {
  .brand-flow { display: none; }
}