/* 随思 SuiSi — minimalist editorial marketing site.
   Warm monochrome canvas, teal brand accent (from the logo mark),
   1px hairline structure, scarce color, quiet motion. */

:root {
  color-scheme: light;

  /* Canvas + surfaces (warm monochrome) */
  --bg: #f7f6f3;
  --surface: #ffffff;
  --surface-soft: #fbfbfa;
  --surface-sunken: #f2f0eb;

  /* Ink */
  --ink: #1a1a17;
  --ink-soft: #3b3a35;
  --muted: #6f6d66;
  --faint: #9a978e;

  /* Hairlines */
  --line: #e6e3dc;
  --line-soft: #eeece6;
  --line-strong: #d8d4ca;

  /* Brand — teal, taken from the logo arc. One accent, locked. */
  --accent: #157a6e;
  --accent-deep: #0f5a51;
  --accent-tint: #e8f1ef;
  --accent-tint-line: #cfe3df;

  /* Dark footer anchor */
  --ink-panel: #14140f;
  --ink-panel-soft: #1f1e18;
  --ink-panel-line: #33322b;
  --on-panel: #f4f3ee;
  --on-panel-muted: #9d9a90;

  /* Radius scale — crisp, one system: cards 12, buttons 8, tags pill */
  --r-card: 12px;
  --r-btn: 8px;
  --r-inner: 8px;

  --shadow-card: 0 1px 2px rgba(26, 26, 23, 0.04), 0 12px 32px rgba(26, 26, 23, 0.05);
  --shadow-frame: 0 2px 4px rgba(26, 26, 23, 0.04), 0 30px 70px rgba(26, 26, 23, 0.1);

  --page: min(1180px, calc(100% - 3rem));
  --page-narrow: min(960px, calc(100% - 3rem));

  --font-sans: "PingFang SC", "HarmonyOS Sans SC", "Noto Sans SC", "Microsoft YaHei",
    "SF Pro Display", -apple-system, BlinkMacSystemFont, "Helvetica Neue", "Segoe UI",
    ui-sans-serif, system-ui, sans-serif;
  --font-mono: "SF Mono", "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --ease: cubic-bezier(0.16, 1, 0.3, 1);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

::selection {
  background: var(--accent-tint);
  color: var(--accent-deep);
}

a {
  color: inherit;
  text-decoration: none;
}

img {
  display: block;
  max-width: 100%;
}

h1,
h2,
h3,
p {
  margin: 0;
}

/* ============ Header ============ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  gap: 1rem;
  height: 68px;
  padding: 0 clamp(1.25rem, 4vw, 3rem);
  background: rgba(247, 246, 243, 0.72);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color 240ms var(--ease), background 240ms var(--ease);
}

.site-header.is-scrolled {
  border-bottom-color: var(--line);
  background: rgba(247, 246, 243, 0.9);
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 600;
  font-size: 1.1rem;
  letter-spacing: -0.01em;
}

.brand-mark {
  width: 30px;
  height: 22px;
  object-fit: contain;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.9rem;
  margin-left: 2.6rem;
  color: var(--muted);
  font-size: 0.94rem;
  font-weight: 500;
}

.nav-links a,
.nav-placeholder {
  transition: color 160ms var(--ease);
}

.nav-links a:hover {
  color: var(--ink);
}

.nav-placeholder {
  cursor: default;
}

.header-contact {
  display: inline-flex;
  align-items: baseline;
  gap: 0.5rem;
  margin-left: auto;
  padding: 0.3rem 0.55rem;
  border: 0;
  border-radius: var(--r-btn);
  background: transparent;
  font: inherit;
  font-size: 0.92rem;
  white-space: nowrap;
  cursor: pointer;
  transition: background 160ms var(--ease);
}

.header-contact:hover {
  background: var(--surface);
}

.header-contact-label {
  color: var(--muted);
  font-weight: 500;
}

.header-contact-email {
  display: inline-grid;
  grid-template-columns: 0fr;
  overflow: hidden;
  color: var(--ink);
  font-weight: 600;
  letter-spacing: 0.01em;
  opacity: 0;
  transition: grid-template-columns 260ms var(--ease), opacity 200ms var(--ease);
}

.header-contact-email > span {
  min-width: 0;
}

.header-contact[aria-expanded="true"] .header-contact-email {
  grid-template-columns: 1fr;
  opacity: 1;
}

.contact-inline {
  cursor: text;
  user-select: text;
}

.footer-contact {
  color: var(--muted);
  white-space: nowrap;
}

/* ============ Hero — left-aligned editorial ============ */
.hero {
  position: relative;
  padding: clamp(8rem, 12vw, 10.5rem) 0 clamp(3.5rem, 6vw, 5.5rem);
  overflow: hidden;
}

/* Quiet ambient warmth — soft radial, no photography */
.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    radial-gradient(60% 55% at 82% 8%, rgba(21, 122, 110, 0.07), transparent 70%),
    radial-gradient(50% 40% at 6% 0%, rgba(21, 122, 110, 0.04), transparent 70%);
}

.hero-content {
  position: relative;
  z-index: 1;
  width: var(--page);
  margin: 0 auto;
  display: grid;
  gap: clamp(3rem, 6vw, 5rem);
}

.hero-copy {
  max-width: 780px;
}

h1 {
  margin: 0;
  color: #000000;
  font-size: clamp(2.6rem, 5.2vw, 4.4rem);
  font-weight: 400;
  line-height: 1.04;
  letter-spacing: -0.03em;
  text-wrap: balance;
}

.hero-line {
  display: block;
}

.hero-line:last-child {
  color: #000000;
}

.hero-lead {
  max-width: 620px;
  margin-top: 1.5rem;
  color: var(--muted);
  font-size: 1.12rem;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.85rem;
  margin-top: 2.2rem;
}

.primary-btn,
.secondary-btn,
.tertiary-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 50px;
  padding: 0 1.5rem;
  border-radius: var(--r-btn);
  font-size: 1rem;
  font-weight: 600;
  transition: background 160ms var(--ease), border-color 160ms var(--ease),
    color 160ms var(--ease), transform 120ms var(--ease);
}

.primary-btn,
.secondary-btn {
  background: var(--surface);
  color: var(--ink);
  border: 1px solid var(--line-strong);
}

.primary-btn:hover,
.secondary-btn:hover {
  background: var(--surface-sunken);
  border-color: var(--line-strong);
  color: var(--ink);
}

.tertiary-btn {
  padding: 0 0.6rem;
  color: var(--muted);
  background: transparent;
  border: 1px solid transparent;
}

.tertiary-btn:hover {
  color: var(--ink);
}

.primary-btn:active,
.secondary-btn:active,
.tertiary-btn:active {
  transform: scale(0.98);
}

.supported-row {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.6rem 1.4rem;
  margin-top: 2.6rem;
  padding-top: 1.7rem;
  border-top: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 0.95rem;
  font-weight: 500;
}

.support-label {
  color: var(--faint);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* ============ Hero product frame ============ */
.product-stage {
  position: relative;
  width: 100%;
}

.screenshot-frame {
  position: relative;
  overflow: hidden;
  border: 0;
  border-radius: 14px;
  background: #ffffff;
  box-shadow: none;
}

.screenshot-frame img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: inherit;
}

/* ============ Agent showcase ============ */
.agent-showcase {
  padding: clamp(5rem, 9vw, 8rem) 0;
}

.agent-showcase-shell {
  display: grid;
  grid-template-columns: 190px minmax(0, 1fr);
  gap: clamp(2.5rem, 5vw, 5rem);
  width: var(--page);
  margin: 0 auto;
}

.agent-nav {
  --indicator-y: 0px;
  position: sticky;
  top: 108px;
  align-self: start;
  display: grid;
  gap: 1.15rem;
  padding-left: 1.3rem;
  border-left: 1px solid var(--line);
}

.agent-nav::before {
  content: "";
  position: absolute;
  left: -1px;
  top: var(--indicator-y);
  width: 2px;
  height: 1.35rem;
  background: var(--accent);
  border-radius: 999px;
  transition: top 260ms var(--ease);
}

.agent-nav a {
  color: var(--faint);
  font-size: 0.95rem;
  font-weight: 500;
  line-height: 1.4;
  transition: color 180ms var(--ease);
}

.agent-nav a:hover,
.agent-nav a.is-active {
  color: var(--ink);
}

.agent-panels {
  display: grid;
  gap: clamp(4rem, 7vw, 6.5rem);
}

.agent-panel {
  display: grid;
  gap: 2rem;
  scroll-margin-top: 108px;
}

.agent-panel + .agent-panel {
  padding-top: clamp(4rem, 7vw, 6.5rem);
  border-top: 1px solid var(--line);
}

.agent-panel-copy {
  max-width: 640px;
}

.agent-panel-copy h2 {
  color: var(--ink);
  font-size: clamp(1.9rem, 3.4vw, 2.9rem);
  font-weight: 400;
  line-height: 1.12;
  letter-spacing: -0.025em;
  text-wrap: balance;
}

.agent-panel-copy p {
  margin-top: 1.05rem;
  color: var(--muted);
  font-size: 1.05rem;
  line-height: 1.75;
}

/* Panel visuals — flat surface tiles, no photography */
.agent-visual {
  display: grid;
  place-items: center;
  padding: clamp(1.5rem, 4vw, 3rem);
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  background:
    radial-gradient(80% 80% at 50% 0%, rgba(21, 122, 110, 0.05), transparent 70%),
    var(--surface-soft);
}

.visual-live {
  justify-items: start;
  padding: 0;
  border: 0;
  background: transparent;
}

.visual-live img {
  width: min(860px, 100%);
  border: 0;
  border-radius: 16px;
  box-shadow: none;
}

.answer-card,
.quiz-board {
  width: min(680px, 100%);
  border: 1px solid var(--line);
  border-radius: var(--r-inner);
  background: var(--surface);
  box-shadow: var(--shadow-card);
  overflow: hidden;
}

/* Answer card */
.answer-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.9rem 1.1rem;
  border-bottom: 1px solid var(--line-soft);
}

.answer-toolbar strong {
  color: var(--ink);
  font-weight: 600;
}

.answer-toolbar span {
  color: var(--faint);
  font-size: 0.86rem;
}

.answer-question {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 0.85rem;
  margin: 1.1rem;
  padding: 0.95rem;
  border: 1px solid var(--line-soft);
  border-radius: var(--r-inner);
  background: var(--surface-sunken);
}

.answer-question b {
  display: inline-grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: var(--r-btn);
  background: var(--ink);
  color: var(--bg);
  font-size: 0.8rem;
}

.answer-question p,
.quiz-solution p {
  color: var(--ink-soft);
  line-height: 1.65;
}

.answer-list {
  margin: 1.1rem;
  padding: 0.95rem 1.1rem;
  border: 1px solid var(--accent-tint-line);
  border-radius: var(--r-inner);
  background: var(--accent-tint);
}

.answer-list strong {
  color: var(--accent-deep);
  font-weight: 600;
}

.answer-list ol {
  display: grid;
  gap: 0.45rem;
  margin: 0.7rem 0 0;
  padding-left: 1.2rem;
  color: var(--ink-soft);
  line-height: 1.55;
}

/* Agent image carousel */
.visual-answer {
  padding: 0;
  border: 0;
  background: transparent;
}

.agent-carousel {
  position: relative;
  width: min(860px, 100%);
}

.agent-carousel-viewport {
  overflow: hidden;
  border-radius: 16px;
  background: var(--surface);
  box-shadow: var(--shadow-card);
}

.agent-carousel-track {
  display: flex;
  margin: 0;
  padding: 0;
  list-style: none;
  transition: transform 480ms var(--ease);
}

.agent-slide {
  flex: 0 0 100%;
  min-width: 0;
}

.agent-slide img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: inherit;
}

.agent-carousel-arrow {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.86);
  color: var(--ink);
  cursor: pointer;
  backdrop-filter: blur(6px);
  box-shadow: var(--shadow-card);
  transition: background 180ms var(--ease), transform 180ms var(--ease), opacity 180ms var(--ease);
}

.agent-carousel-arrow svg {
  width: 22px;
  height: 22px;
}

.agent-carousel-arrow.is-prev {
  left: clamp(-22px, -1.4vw, -12px);
}

.agent-carousel-arrow.is-next {
  right: clamp(-22px, -1.4vw, -12px);
}

.agent-carousel-arrow:hover {
  background: #ffffff;
  transform: translateY(-50%) scale(1.06);
}

.agent-carousel-dots {
  display: flex;
  justify-content: center;
  gap: 0.55rem;
  margin-top: 1.15rem;
}

.agent-carousel-dot {
  width: 8px;
  height: 8px;
  padding: 0;
  border: 0;
  border-radius: 999px;
  background: var(--line);
  cursor: pointer;
  transition: background 180ms var(--ease), width 220ms var(--ease);
}

.agent-carousel-dot.is-active {
  width: 26px;
  background: var(--accent);
}

@media (max-width: 720px) {
  .agent-carousel-arrow {
    width: 38px;
    height: 38px;
  }
  .agent-carousel-arrow.is-prev {
    left: 8px;
  }
  .agent-carousel-arrow.is-next {
    right: 8px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .agent-carousel-track {
    transition: none;
  }
}

/* Knowledge base screenshot */
.visual-quiz {
  justify-items: start;
  padding: 0;
  border: 0;
  background: transparent;
}

.visual-quiz img {
  width: min(860px, 100%);
  border: 1px solid var(--line);
  border-radius: 16px;
  box-shadow: var(--shadow-card);
}

.visual-memory {
  justify-items: start;
  padding: 0;
  border: 0;
  background: transparent;
}

/* Quiz / knowledge board */
.quiz-board {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 250px;
}

.quiz-code {
  display: grid;
  gap: 0.5rem;
  padding: 1.3rem;
  background: var(--ink-panel);
  color: #c9c6bc;
  font-family: var(--font-mono);
  font-size: 0.86rem;
  line-height: 1.5;
}

.quiz-code span:first-child {
  color: #6fd3c4;
}

.quiz-solution {
  display: grid;
  align-content: center;
  gap: 0.6rem;
  padding: 1.3rem;
}

.quiz-solution strong {
  color: var(--ink);
  font-weight: 600;
}

/* Panel points */
.agent-points {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.8rem;
}

.agent-points div {
  display: grid;
  gap: 0.5rem;
  padding-top: 1.1rem;
  border-top: 1px solid var(--line);
}

.agent-points strong {
  color: var(--ink);
  font-size: 0.98rem;
  font-weight: 600;
}

.agent-points span {
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.7;
}

/* ============ Start section ============ */
.start-section {
  padding: clamp(5rem, 9vw, 8rem) 0;
  border-top: 1px solid var(--line);
  background: var(--surface-soft);
}

.start-inner {
  width: var(--page-narrow);
  margin: 0 auto;
}

.start-heading {
  margin-bottom: 3rem;
}

.start-heading > span {
  display: block;
  margin-bottom: 0.85rem;
  color: var(--accent-deep);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.start-heading h2,
.faq-heading h2 {
  color: var(--ink);
  font-size: clamp(2rem, 4vw, 3.2rem);
  font-weight: 400;
  line-height: 1.1;
  letter-spacing: -0.03em;
}

.start-heading h2 span {
  display: block;
}

.start-heading h2 span + span {
  color: var(--faint);
}

.start-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border: 1px solid var(--line);
  border-radius: var(--r-card);
  overflow: hidden;
  background: var(--surface);
}

.start-steps article {
  display: grid;
  align-content: start;
  gap: 0.8rem;
  padding: 1.9rem 1.6rem;
}

.start-steps article + article {
  border-left: 1px solid var(--line);
}

.start-steps article > span {
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 0.9rem;
  font-weight: 600;
}

.start-steps h3 {
  color: var(--ink);
  font-size: 1.02rem;
  font-weight: 600;
  line-height: 1.35;
}

.start-steps p {
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.7;
}

.start-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin-top: 2.4rem;
}

.start-secondary,
.footer-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 1.3rem;
  border-radius: var(--r-btn);
  font-size: 0.95rem;
  font-weight: 600;
  transition: background 160ms var(--ease), border-color 160ms var(--ease),
    color 160ms var(--ease), transform 120ms var(--ease);
}

.footer-cta {
  background: var(--ink);
  color: var(--bg);
  border: 1px solid var(--ink);
}

.footer-cta:hover {
  background: var(--surface-sunken);
  border-color: var(--surface-sunken);
  color: var(--ink-panel);
}

.start-secondary {
  border: 1px solid var(--line-strong);
  color: var(--ink);
  background: var(--surface);
}

.start-secondary:hover {
  background: var(--surface-sunken);
  border-color: var(--line-strong);
  color: var(--ink);
}

.start-secondary.is-disabled {
  cursor: default;
}

.start-secondary.is-disabled:hover {
  background: var(--surface);
}

.start-secondary:not(.is-disabled):active,
.footer-cta:active {
  transform: scale(0.98);
}

.start-contact {
  gap: 0;
  font: inherit;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
}

.start-contact-label {
  color: var(--ink);
}

.start-contact-email {
  display: inline-grid;
  grid-template-columns: 0fr;
  overflow: hidden;
  color: var(--accent-deep);
  letter-spacing: 0.01em;
  opacity: 0;
  transition: grid-template-columns 260ms var(--ease), opacity 200ms var(--ease);
}

.start-contact-email > span {
  min-width: 0;
  white-space: nowrap;
}

.start-contact[aria-expanded="true"] .start-contact-email {
  grid-template-columns: 1fr;
  opacity: 1;
  margin-left: 0.5rem;
}

/* ============ FAQ ============ */
.faq-section {
  padding: clamp(5rem, 9vw, 8rem) 0;
  border-top: 1px solid var(--line);
}

.faq-inner {
  width: min(760px, calc(100% - 3rem));
  margin: 0 auto;
}

.faq-heading {
  margin-bottom: 2.6rem;
}

.faq-heading > span {
  display: block;
  margin-bottom: 0.7rem;
  color: var(--accent-deep);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.faq-list details {
  border-bottom: 1px solid var(--line);
}

.faq-list summary {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 24px;
  gap: 1rem;
  align-items: center;
  min-height: 66px;
  cursor: pointer;
  list-style: none;
  color: var(--ink);
  font-size: 1.02rem;
  font-weight: 600;
}

.faq-list summary::-webkit-details-marker {
  display: none;
}

.faq-list summary i {
  position: relative;
  width: 20px;
  height: 20px;
}

.faq-list summary i::before,
.faq-list summary i::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 12px;
  height: 1.5px;
  background: var(--muted);
  transform: translate(-50%, -50%);
  transition: transform 220ms var(--ease), background 160ms var(--ease);
}

.faq-list summary i::after {
  transform: translate(-50%, -50%) rotate(90deg);
}

.faq-list details[open] summary i::after {
  transform: translate(-50%, -50%) rotate(0deg);
}

.faq-list details[open] summary i::before,
.faq-list details[open] summary i::after {
  background: var(--ink);
}

.faq-list p,
.faq-answer {
  margin: -0.2rem 0 1.5rem;
  color: var(--muted);
  font-size: 0.98rem;
  line-height: 1.8;
}

.faq-answer p {
  margin: 0;
}

.faq-answer ol {
  display: grid;
  gap: 1rem;
  margin: 1rem 0 0;
  padding-left: 1.25rem;
}

.faq-answer li {
  padding-left: 0.2rem;
}

.faq-answer strong {
  display: block;
  margin-bottom: 0.2rem;
  color: var(--ink);
  font-weight: 600;
}

.faq-answer span {
  display: block;
}

/* ============ Footer ============ */
.site-footer {
  background: var(--ink-panel);
  color: var(--on-panel-muted);
  padding: clamp(4rem, 7vw, 5.5rem) 0 2.6rem;
}

.site-footer-inner,
.footer-bottom {
  width: var(--page);
  margin: 0 auto;
}

.site-footer-inner {
  display: grid;
  grid-template-columns: minmax(240px, 1.4fr) repeat(3, minmax(110px, 0.7fr));
  gap: 3rem;
  align-items: start;
}

.footer-brand {
  display: grid;
  justify-items: start;
  gap: 1.2rem;
}

.footer-logo {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--on-panel);
  font-size: 1.05rem;
  font-weight: 600;
}

.footer-logo img {
  width: 28px;
  height: 20px;
  object-fit: contain;
}

.footer-brand p {
  max-width: 260px;
  color: var(--on-panel-muted);
  font-size: 0.96rem;
  line-height: 1.7;
}

.footer-cta {
  background: var(--on-panel);
  color: var(--ink-panel);
  border-color: var(--on-panel);
}

.footer-cta:hover {
  background: var(--surface-sunken);
  border-color: var(--surface-sunken);
  color: var(--ink-panel);
}

.footer-column {
  display: grid;
  gap: 0.85rem;
}

.footer-column strong {
  margin-bottom: 0.3rem;
  color: var(--on-panel);
  font-size: 0.88rem;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.footer-column a,
.footer-placeholder {
  color: var(--on-panel-muted);
  font-size: 0.94rem;
  transition: color 160ms var(--ease);
}

.footer-column a:hover {
  color: var(--on-panel);
}

.footer-placeholder {
  cursor: default;
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  margin-top: 3.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--ink-panel-line);
  color: var(--on-panel-muted);
  font-size: 0.9rem;
}

.language-switch {
  display: inline-flex;
  align-items: center;
}

.language-switch a {
  color: var(--on-panel-muted);
  transition: color 160ms var(--ease);
}

.language-switch a:hover {
  color: var(--on-panel);
}

.language-switch a[aria-current="true"] {
  color: var(--on-panel);
}

.language-switch a + a::before {
  content: "";
  display: inline-block;
  width: 1px;
  height: 0.9em;
  margin: 0 0.6rem;
  vertical-align: -0.1em;
  background: var(--ink-panel-line);
}

/* ============ Quiet scroll-reveal ============ */
@media (prefers-reduced-motion: no-preference) {
  .reveal {
    opacity: 0;
    transform: translateY(14px);
    transition: opacity 700ms var(--ease), transform 700ms var(--ease);
  }

  .reveal.is-visible {
    opacity: 1;
    transform: none;
  }
}

/* ============ Responsive ============ */
@media (max-width: 1024px) {
  .nav-links {
    display: none;
  }

  .agent-showcase-shell {
    grid-template-columns: 1fr;
    gap: 2.4rem;
  }

  .agent-nav {
    position: sticky;
    top: 68px;
    z-index: 30;
    display: flex;
    gap: 1.3rem;
    padding: 0.8rem 0.2rem;
    margin: 0 -0.2rem;
    overflow-x: auto;
    border-left: 0;
    border-bottom: 1px solid var(--line);
    background: rgba(247, 246, 243, 0.92);
    backdrop-filter: blur(14px);
    scrollbar-width: none;
  }

  .agent-nav::-webkit-scrollbar {
    display: none;
  }

  .agent-nav::before {
    content: none;
  }

  .agent-nav a {
    flex: 0 0 auto;
    white-space: nowrap;
  }

  .agent-nav a.is-active {
    color: var(--accent-deep);
  }
}

@media (max-width: 760px) {
  body {
    font-size: 15px;
  }

  .hero {
    padding-top: 6.5rem;
  }

  .hero-actions {
    gap: 0.7rem;
  }

  .primary-btn,
  .secondary-btn {
    flex: 1 1 auto;
  }

  .supported-row {
    gap: 0.5rem 1rem;
  }

  .quiz-board {
    grid-template-columns: 1fr;
  }

  .agent-points {
    grid-template-columns: 1fr;
    gap: 1.4rem;
  }

  .start-steps {
    grid-template-columns: 1fr;
  }

  .start-steps article + article {
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .site-footer-inner {
    grid-template-columns: repeat(2, 1fr);
    gap: 2.4rem;
  }

  .footer-brand {
    grid-column: 1 / -1;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 1.2rem;
  }
}

@media (max-width: 460px) {
  .site-footer-inner {
    grid-template-columns: 1fr;
  }
}