/* KinPath — thekinpath.com
   Palette is taken from the app icon: the blue gradient behind the figures,
   the white nodes, and the one coral connector. */

:root {
  --blue-deep: #0B3FD4;
  --blue: #0B57E8;
  --blue-bright: #0A84FF;
  --coral: #F0846F;
  --pink: #E86FA8;

  --ink: #0E1424;
  --ink-soft: #38405A;
  --muted: #616B84;
  --line: #E3E8F2;
  --bg: #FFFFFF;
  --surface: #F5F7FC;
  --surface-2: #EDF1FA;
  --card: #FFFFFF;
  --shadow: 0 1px 2px rgba(14, 20, 36, 0.04), 0 12px 32px rgba(14, 20, 36, 0.06);

  --radius: 20px;
  --radius-sm: 12px;
  --maxw: 1120px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --ink: #EEF2FB;
    --ink-soft: #C2CADB;
    --muted: #939DB5;
    --line: #242B3D;
    --bg: #0B0F1A;
    --surface: #121826;
    --surface-2: #171F30;
    --card: #131A29;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 12px 32px rgba(0, 0, 0, 0.32);
  }
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; }

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

.wrap { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---------- header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: saturate(180%) blur(16px);
  -webkit-backdrop-filter: saturate(180%) blur(16px);
  border-bottom: 1px solid var(--line);
}

.site-header .wrap {
  display: flex;
  align-items: center;
  gap: 16px;
  height: 62px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 650;
  letter-spacing: -0.01em;
  text-decoration: none;
  font-size: 17px;
}

.brand img { width: 28px; height: 28px; border-radius: 7px; }

.site-nav {
  margin-inline-start: auto;
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: 15px;
}

.site-nav a {
  text-decoration: none;
  color: var(--muted);
  padding: 6px 11px;
  border-radius: 999px;
  white-space: nowrap;
}

.site-nav a:hover { color: var(--ink); background: var(--surface-2); }

.lang-switch {
  border: 1px solid var(--line);
  color: var(--ink-soft) !important;
  font-weight: 550;
  font-size: 13px !important;
  padding: 5px 12px !important;
}

/* ---------- hero ---------- */

.hero {
  position: relative;
  overflow: hidden;
  padding: 88px 0 76px;
  background:
    radial-gradient(1000px 460px at 78% -8%, color-mix(in srgb, var(--blue-bright) 16%, transparent), transparent 68%),
    radial-gradient(760px 420px at 8% 6%, color-mix(in srgb, var(--coral) 11%, transparent), transparent 66%);
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.12fr) minmax(0, 0.88fr);
  gap: 56px;
  align-items: center;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.02em;
  color: var(--blue);
  background: color-mix(in srgb, var(--blue) 10%, transparent);
  border-radius: 999px;
  padding: 5px 13px;
  margin: 0 0 22px;
}

/* The Chinese headline is one unbreakable 10-glyph line, so the ceiling here
   is set by the hero column's width, not by taste. */
h1 {
  font-size: clamp(31px, 4.3vw, 49px);
  line-height: 1.16;
  letter-spacing: -0.028em;
  font-weight: 700;
  margin: 0 0 20px;
}

.hero .lede {
  font-size: clamp(17px, 1.6vw, 19px);
  color: var(--ink-soft);
  margin: 0 0 32px;
  max-width: 34em;
}

.cta-row { display: flex; flex-wrap: wrap; align-items: center; gap: 14px; }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  border-radius: 999px;
  padding: 13px 25px;
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  border: 1px solid transparent;
  transition: transform 0.15s ease, background 0.15s ease;
}

.btn-primary {
  background: linear-gradient(135deg, var(--blue-deep), var(--blue-bright));
  color: #fff;
  cursor: default;
  box-shadow: 0 8px 24px color-mix(in srgb, var(--blue) 30%, transparent);
}

.btn-primary .btn-note {
  font-size: 12px;
  font-weight: 500;
  opacity: 0.82;
  border-inline-start: 1px solid rgba(255, 255, 255, 0.34);
  padding-inline-start: 9px;
  margin-inline-start: 2px;
}

.btn-ghost { border-color: var(--line); color: var(--ink); background: var(--card); }
.btn-ghost:hover { background: var(--surface-2); transform: translateY(-1px); }

.hero-meta { margin: 18px 0 0; font-size: 14px; color: var(--muted); }

/* ---------- chain visual ---------- */

.chain-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 26px;
  padding: 26px 24px 24px;
  box-shadow: var(--shadow);
}

.chain-card h3 {
  margin: 0 0 18px;
  font-size: 15px;
  font-weight: 600;
  color: var(--muted);
  letter-spacing: -0.01em;
}

.chain {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin-bottom: 22px;
}

.chain-step { display: flex; align-items: center; gap: 14px; }

.node {
  flex: none;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-size: 15px;
  font-weight: 600;
  color: #fff;
  background: linear-gradient(140deg, var(--blue-deep), var(--blue-bright));
}

.node-self { background: linear-gradient(140deg, #2A3350, #4A5578); }
.node-answer { background: linear-gradient(140deg, #E86A52, var(--coral)); }

.chain-step .label { font-size: 15px; font-weight: 550; }
.chain-step .label small { display: block; font-size: 12.5px; font-weight: 450; color: var(--muted); }

.connector {
  width: 46px;
  flex: none;
  display: grid;
  place-items: center;
  height: 26px;
}

.connector i {
  display: block;
  width: 2px;
  height: 100%;
  background: linear-gradient(var(--blue-bright), var(--blue));
  border-radius: 2px;
  opacity: 0.45;
}

.connector-row { display: flex; align-items: center; gap: 14px; }
.connector-row span { font-size: 12.5px; color: var(--muted); }

.answer {
  border-top: 1px dashed var(--line);
  padding-top: 18px;
  display: grid;
  gap: 10px;
}

.answer-line { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; }
.answer-line span { font-size: 14px; color: var(--muted); }
.answer-line strong { font-size: 21px; font-weight: 680; letter-spacing: -0.01em; }
.answer-line strong em { font-style: normal; color: var(--muted); font-size: 15px; font-weight: 500; }

/* ---------- sections ---------- */

section { padding: 78px 0; }

.section-head { max-width: 40em; margin: 0 0 44px; }

.section-head .kicker {
  font-size: 13px;
  font-weight: 650;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--blue);
  margin: 0 0 12px;
}

h2 {
  font-size: clamp(26px, 3.3vw, 36px);
  line-height: 1.25;
  letter-spacing: -0.024em;
  font-weight: 690;
  margin: 0 0 14px;
}

.section-head p { color: var(--ink-soft); margin: 0; font-size: 17px; }

.band { background: var(--surface); border-block: 1px solid var(--line); }

/* ---------- steps ---------- */

.steps { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 22px; }

.step {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 24px;
}

.step .num {
  font-size: 13px;
  font-weight: 700;
  color: var(--blue);
  letter-spacing: 0.08em;
  display: block;
  margin-bottom: 12px;
}

.step h3 { margin: 0 0 8px; font-size: 18px; font-weight: 640; letter-spacing: -0.015em; }
.step p { margin: 0; color: var(--ink-soft); font-size: 15.5px; }

/* ---------- features ---------- */

.features { display: grid; grid-template-columns: repeat(6, minmax(0, 1fr)); gap: 20px; }

.feature {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 26px;
  grid-column: span 2;
  display: flex;
  flex-direction: column;
}

/* Nine cards, arranged so no row is left ragged:
   [wide + one] [wide + one] [three] [one + wide]. */
.feature-wide { grid-column: span 4; }

.feature .tag {
  font-size: 12.5px;
  font-weight: 650;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
  margin: 0 0 10px;
}

.feature h3 {
  margin: 0 0 10px;
  font-size: 19px;
  line-height: 1.35;
  font-weight: 640;
  letter-spacing: -0.018em;
}

.feature p { margin: 0; color: var(--ink-soft); font-size: 15.5px; }

.feature .visual { margin-top: auto; padding-top: 22px; }

.feature-accent {
  background: linear-gradient(150deg, var(--blue-deep), var(--blue-bright));
  border-color: transparent;
  color: #fff;
}
.feature-accent .tag { color: rgba(255, 255, 255, 0.72); }
.feature-accent p { color: rgba(255, 255, 255, 0.88); }

/* small visuals inside feature cards */

.chips { display: flex; flex-wrap: wrap; gap: 8px; }

.chip {
  font-size: 14px;
  font-weight: 550;
  padding: 7px 14px;
  border-radius: 999px;
  background: var(--surface-2);
  border: 1px solid var(--line);
}

.feature-accent .chip {
  background: rgba(255, 255, 255, 0.16);
  border-color: rgba(255, 255, 255, 0.24);
  color: #fff;
}

.chip-coral { background: color-mix(in srgb, var(--coral) 16%, transparent); border-color: color-mix(in srgb, var(--coral) 34%, transparent); }

.edge-key { display: grid; gap: 9px; }
.edge-key div { display: flex; align-items: center; gap: 10px; font-size: 14px; color: var(--muted); }
.edge-key i { width: 30px; height: 3px; border-radius: 3px; display: block; }
.edge-blue { background: var(--blue-bright); }
.edge-pink { background: var(--pink); }
.edge-orange { background: var(--coral); }

.rank-row { display: flex; gap: 8px; flex-wrap: wrap; }
.rank-row b {
  font-size: 15px;
  font-weight: 620;
  padding: 8px 13px;
  border-radius: var(--radius-sm);
  background: var(--surface-2);
  border: 1px solid var(--line);
}

.entry-demo { display: grid; gap: 7px; }
.entry-demo span {
  font-size: 14.5px;
  padding: 8px 13px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.16);
  border: 1px solid rgba(255, 255, 255, 0.22);
  display: flex;
  justify-content: space-between;
}
.entry-demo span em { font-style: normal; opacity: 0.7; font-size: 13px; }

/* ---------- privacy strip ---------- */

.privacy-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 20px; }

.privacy-item { border-top: 2px solid var(--blue); padding-top: 16px; }
.privacy-item h3 { margin: 0 0 6px; font-size: 16px; font-weight: 640; }
.privacy-item p { margin: 0; font-size: 15px; color: var(--ink-soft); }

/* ---------- prose pages ---------- */

.page-head { padding: 62px 0 10px; }
.page-head h1 { font-size: clamp(30px, 4vw, 42px); margin-bottom: 10px; }
.page-head p { color: var(--muted); margin: 0; font-size: 15px; }

.prose { padding: 26px 0 90px; max-width: 44em; }
.prose h2 { font-size: 22px; margin: 42px 0 12px; letter-spacing: -0.018em; }
.prose h3 { font-size: 17.5px; margin: 28px 0 8px; font-weight: 640; }
.prose p { color: var(--ink-soft); margin: 0 0 14px; }
.prose ul { color: var(--ink-soft); padding-inline-start: 22px; margin: 0 0 16px; }
.prose li { margin-bottom: 7px; }
.prose a { color: var(--blue); text-decoration-thickness: 1px; text-underline-offset: 2px; }
.prose strong { color: var(--ink); font-weight: 620; }

.callout {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 24px;
  margin: 26px 0;
}
.callout p:last-child { margin-bottom: 0; }

/* ---------- footer ---------- */

.site-footer {
  border-top: 1px solid var(--line);
  background: var(--surface);
  padding: 40px 0;
  font-size: 14.5px;
  color: var(--muted);
}

.site-footer .wrap { display: flex; flex-wrap: wrap; gap: 16px 28px; align-items: center; }
.site-footer nav { display: flex; gap: 20px; margin-inline-start: auto; flex-wrap: wrap; }
.site-footer a { text-decoration: none; }
.site-footer a:hover { color: var(--ink); }

/* ---------- responsive ---------- */

@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; gap: 40px; }
  .steps { grid-template-columns: 1fr; }
  .features { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .feature, .feature-wide { grid-column: span 1; }
  .privacy-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 640px) {
  body { font-size: 16px; }
  .hero { padding: 56px 0 52px; }
  section { padding: 56px 0; }
  .features, .privacy-grid { grid-template-columns: 1fr; }
  .site-nav a:not(.lang-switch) { display: none; }
  .site-footer .wrap { flex-direction: column; align-items: flex-start; }
  .site-footer nav { margin-inline-start: 0; gap: 16px; }
}