/* TreeletHub marketing — minimal, readable, print-friendly */
:root {
  --bg: #fafaf9;
  --surface: #ffffff;
  --text: #1c1917;
  --muted: #57534e;
  --line: #e7e5e4;
  --accent: #3f6f46;
  --accent-soft: #e8f1e9;
  --radius: 12px;
  --shadow: 0 1px 2px rgba(28, 25, 23, 0.06), 0 8px 24px rgba(28, 25, 23, 0.06);
  --font: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --max: 720px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 1.0625rem;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

a:hover {
  text-decoration: none;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  padding: 0.5rem 1rem;
  background: var(--text);
  color: var(--surface);
  z-index: 100;
}

.skip-link:focus {
  left: 1rem;
  top: 1rem;
}

.wrap {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 1.25rem 4rem;
}

header.site {
  padding: 1.25rem 0 2.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  border-bottom: 1px solid var(--line);
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--text);
  text-decoration: none;
}

.brand:hover {
  color: var(--accent);
}

.brand-logo {
  width: 36px;
  height: 36px;
  border-radius: 22%;
  object-fit: cover;
  flex-shrink: 0;
  box-shadow: 0 1px 2px rgba(28, 25, 23, 0.08);
}

.hero-brand {
  margin-bottom: 1.35rem;
}

.hero-logo {
  width: 88px;
  height: 88px;
  border-radius: 22%;
  object-fit: cover;
  display: block;
  box-shadow: var(--shadow);
}

.lang-switch {
  display: flex;
  gap: 0.35rem;
  font-size: 0.875rem;
}

.lang-switch a {
  padding: 0.35rem 0.65rem;
  border-radius: 999px;
  color: var(--muted);
  text-decoration: none;
  border: 1px solid transparent;
}

.lang-switch a:hover {
  color: var(--text);
  border-color: var(--line);
  background: var(--surface);
}

.lang-switch a[aria-current="page"] {
  color: var(--text);
  background: var(--surface);
  border-color: var(--line);
  font-weight: 500;
}

.hero {
  padding: 3rem 0 2.5rem;
}

.hero h1 {
  margin: 0 0 1rem;
  font-size: clamp(1.85rem, 4.5vw, 2.35rem);
  line-height: 1.2;
  letter-spacing: -0.03em;
  font-weight: 700;
}

.lead {
  margin: 0 0 1.75rem;
  font-size: 1.125rem;
  color: var(--muted);
  max-width: 42rem;
}

.lead-tight {
  margin-bottom: 1.1rem;
}

.lead-tight:last-of-type {
  margin-bottom: 1.75rem;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  align-items: center;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.65rem 1.15rem;
  border-radius: 999px;
  font-size: 0.9375rem;
  font-weight: 600;
  text-decoration: none;
  border: 1px solid transparent;
  cursor: default;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
}

.btn-primary[href]:hover {
  filter: brightness(1.05);
}

.btn-ghost {
  background: var(--surface);
  color: var(--text);
  border-color: var(--line);
  box-shadow: var(--shadow);
}

.btn-ghost[href]:hover {
  border-color: #d6d3d1;
}

.btn[aria-disabled="true"] {
  opacity: 0.55;
  pointer-events: none;
}

.note {
  font-size: 0.8125rem;
  color: var(--muted);
  margin-top: 0.75rem;
}

.section-note {
  margin-top: 1rem;
  margin-bottom: 0;
  max-width: 42rem;
}

section {
  margin-top: 2.75rem;
}

section h2 {
  margin: 0 0 1rem;
  font-size: 1.125rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.25rem 1.35rem;
  box-shadow: var(--shadow);
}

.card + .card {
  margin-top: 0.85rem;
}

.card h3 {
  margin: 0 0 0.35rem;
  font-size: 1rem;
  font-weight: 600;
}

.card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.98rem;
}

.steps {
  counter-reset: step;
  list-style: none;
  padding: 0;
  margin: 0;
}

.steps li {
  position: relative;
  padding-left: 2.75rem;
  margin-bottom: 1.1rem;
}

.steps li:last-child {
  margin-bottom: 0;
}

.steps li::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0.1rem;
  width: 1.85rem;
  height: 1.85rem;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 700;
  display: grid;
  place-items: center;
}

.platforms {
  display: grid;
  gap: 0.75rem;
}

@media (min-width: 520px) {
  .platforms {
    grid-template-columns: 1fr 1fr;
  }
}

.pill {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 0.2rem 0.5rem;
  border-radius: 6px;
  margin-bottom: 0.5rem;
}

footer.site {
  margin-top: 3.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--line);
  font-size: 0.875rem;
  color: var(--muted);
}

footer.site nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 0.75rem;
}

footer.site a {
  color: var(--muted);
}

footer.site a:hover {
  color: var(--accent);
}

.copyright {
  margin: 0;
}