:root {
  --ink: #151812;
  --ink-soft: #2e342c;
  --muted: #5f685d;
  --paper: #f7f4ed;
  --paper-deep: #eee8dc;
  --surface: #fffdf8;
  --line: #d8ddcf;
  --green: #2f7d57;
  --green-dark: #205b43;
  --cyan: #197783;
  --amber: #b7791f;
  --shadow: 0 24px 70px rgba(21, 24, 18, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background:
    linear-gradient(180deg, rgba(247, 244, 237, 0.98), rgba(238, 232, 220, 0.82)),
    var(--paper);
  color: var(--ink);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  letter-spacing: 0;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 72px;
  padding: 0 clamp(20px, 5vw, 72px);
  border-bottom: 1px solid rgba(216, 221, 207, 0.72);
  background: rgba(247, 244, 237, 0.86);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  font-weight: 800;
}

.brand-mark {
  width: 34px;
  height: 34px;
  display: block;
  object-fit: cover;
  border-radius: 8px;
  box-shadow: 0 6px 16px rgba(21, 24, 18, 0.12);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: clamp(14px, 3vw, 32px);
  color: var(--muted);
  font-size: 14px;
  font-weight: 650;
}

.nav-links a,
.nav-action {
  transition: color 0.18s ease, border-color 0.18s ease, background 0.18s ease;
}

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

.nav-action {
  border: 1px solid rgba(21, 24, 18, 0.16);
  border-radius: 999px;
  padding: 10px 16px;
  color: var(--ink);
  font-size: 14px;
  font-weight: 760;
}

.nav-action:hover {
  border-color: rgba(47, 125, 87, 0.55);
  background: rgba(47, 125, 87, 0.08);
}

.hero-section {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(360px, 0.98fr);
  align-items: center;
  gap: clamp(36px, 6vw, 86px);
  min-height: calc(100vh - 72px);
  padding: clamp(56px, 8vw, 112px) clamp(20px, 5vw, 72px) 72px;
}

.embed-page .hero-section {
  min-height: calc(100vh - 72px);
}

.embed-page {
  background: transparent;
}

.embed-page main {
  margin-top: 72px;
  background:
    linear-gradient(180deg, rgba(247, 244, 237, 0.98), rgba(238, 232, 220, 0.82)),
    var(--paper);
}

.hero-copy {
  max-width: 760px;
}

.eyebrow {
  margin: 0 0 16px;
  color: var(--green);
  font-size: 12px;
  font-weight: 850;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  letter-spacing: 0;
}

h1 {
  margin: 0;
  font-size: clamp(64px, 11vw, 156px);
  line-height: 0.88;
  font-weight: 900;
}

.hero-statement {
  margin: 22px 0 0;
  color: var(--ink-soft);
  font-size: clamp(30px, 4.4vw, 64px);
  line-height: 1.02;
  font-weight: 840;
}

.hero-description {
  max-width: 680px;
  margin: 28px 0 0;
  color: var(--muted);
  font-size: clamp(18px, 2vw, 24px);
  line-height: 1.65;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 36px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  border-radius: 999px;
  padding: 0 20px;
  font-weight: 800;
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}

.button:hover {
  transform: translateY(-1px);
}

.button.primary {
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--surface);
  box-shadow: 0 16px 30px rgba(21, 24, 18, 0.18);
}

.button.secondary {
  border: 1px solid rgba(21, 24, 18, 0.2);
  color: var(--ink);
  background: rgba(255, 253, 248, 0.52);
}

.path-visual {
  min-width: 0;
}

.path-board {
  position: relative;
  overflow: hidden;
  min-height: 610px;
  border: 1px solid rgba(216, 221, 207, 0.95);
  border-radius: 8px;
  background:
    linear-gradient(135deg, rgba(255, 253, 248, 0.92), rgba(238, 232, 220, 0.72)),
    var(--surface);
  box-shadow: var(--shadow);
}

.path-board::before {
  content: "";
  position: absolute;
  inset: 28px;
  border: 1px solid rgba(21, 24, 18, 0.08);
  border-radius: 6px;
}

.thought-cloud span {
  position: absolute;
  width: 12px;
  height: 12px;
  border-radius: 999px;
  background: rgba(21, 24, 18, 0.18);
}

.thought-cloud span:nth-child(1) {
  top: 108px;
  left: 74px;
}

.thought-cloud span:nth-child(2) {
  top: 178px;
  left: 126px;
  background: rgba(25, 119, 131, 0.56);
}

.thought-cloud span:nth-child(3) {
  top: 260px;
  left: 82px;
}

.thought-cloud span:nth-child(4) {
  top: 338px;
  left: 148px;
  background: rgba(47, 125, 87, 0.52);
}

.thought-cloud span:nth-child(5) {
  top: 414px;
  left: 98px;
}

.thought-cloud span:nth-child(6) {
  top: 134px;
  left: 206px;
}

.thought-cloud span:nth-child(7) {
  top: 292px;
  left: 218px;
  background: rgba(183, 121, 31, 0.48);
}

.thought-cloud span:nth-child(8) {
  top: 476px;
  left: 178px;
}

.path-line {
  position: absolute;
  top: 132px;
  right: 68px;
  width: 48%;
  height: 310px;
}

.path-line::before {
  content: "";
  position: absolute;
  top: 18px;
  right: 18px;
  bottom: 18px;
  left: 18px;
  border-top: 3px solid var(--green);
  border-right: 3px solid var(--green);
  border-bottom: 3px solid var(--green);
  border-radius: 0 120px 120px 0;
}

.node {
  position: absolute;
  z-index: 2;
  width: 38px;
  height: 38px;
  border: 3px solid var(--green);
  border-radius: 999px;
  background: var(--surface);
  box-shadow: 0 10px 24px rgba(47, 125, 87, 0.18);
}

.node-one {
  top: 0;
  left: 0;
}

.node-two {
  top: 0;
  right: 0;
  border-color: var(--cyan);
}

.node-three {
  right: 0;
  bottom: 0;
  border-color: var(--amber);
}

.node-four {
  left: 0;
  bottom: 0;
  background: var(--green);
}

.answer-panel {
  position: absolute;
  right: 48px;
  bottom: 48px;
  left: 48px;
  padding: 24px;
  border: 1px solid rgba(21, 24, 18, 0.1);
  border-radius: 8px;
  background: rgba(255, 253, 248, 0.82);
  box-shadow: 0 16px 38px rgba(21, 24, 18, 0.1);
}

.answer-panel p {
  margin: 0;
  color: var(--muted);
  line-height: 1.55;
}

.answer-panel strong {
  display: block;
  margin: 8px 0 12px;
  color: var(--ink);
  font-size: 22px;
  line-height: 1.28;
}

.section {
  padding: clamp(64px, 9vw, 116px) clamp(20px, 5vw, 72px);
}

.intro-section {
  display: grid;
  grid-template-columns: minmax(240px, 0.9fr) minmax(0, 1.1fr);
  gap: clamp(28px, 6vw, 88px);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: rgba(255, 253, 248, 0.48);
}

.intro-section h2,
.section-heading h2,
.api-copy h2 {
  margin: 0;
  font-size: clamp(34px, 5vw, 76px);
  line-height: 1.05;
  font-weight: 880;
}

.intro-section > p {
  margin: 0;
  color: var(--muted);
  font-size: clamp(18px, 2vw, 23px);
  line-height: 1.75;
}

.section-heading {
  max-width: 760px;
  margin-bottom: 34px;
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--line);
}

.step {
  min-height: 280px;
  padding: clamp(22px, 3vw, 34px);
  background: rgba(255, 253, 248, 0.76);
}

.step span {
  color: var(--green);
  font-size: 13px;
  font-weight: 850;
}

.step h3,
.use-grid h3 {
  margin: 48px 0 12px;
  font-size: 24px;
  line-height: 1.18;
}

.step p,
.use-grid p,
.api-copy p {
  margin: 0;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.7;
}

.use-section {
  background: var(--ink);
  color: var(--surface);
}

.use-section .eyebrow {
  color: #7dd0a8;
}

.use-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  overflow: hidden;
  border: 1px solid rgba(255, 253, 248, 0.16);
  border-radius: 8px;
  background: rgba(255, 253, 248, 0.16);
}

.use-grid article {
  min-height: 250px;
  padding: 28px;
  background: rgba(255, 253, 248, 0.045);
}

.use-grid h3 {
  margin-top: 0;
}

.use-grid p {
  color: rgba(255, 253, 248, 0.72);
}

.api-section {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 470px);
  align-items: start;
  gap: clamp(32px, 6vw, 88px);
}

.api-copy p {
  max-width: 680px;
  margin-top: 24px;
  font-size: 18px;
}

.api-panel {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 253, 248, 0.72);
  box-shadow: var(--shadow);
  padding: 24px;
}

.api-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 18px;
  padding: 16px 0;
  border-bottom: 1px solid rgba(21, 24, 18, 0.1);
}

.api-row:first-child {
  padding-top: 0;
}

.api-row span {
  color: var(--muted);
  font-size: 14px;
}

.api-row strong {
  text-align: right;
  font-size: 16px;
}

.api-panel .button {
  width: 100%;
  margin-top: 24px;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 30px clamp(20px, 5vw, 72px);
  border-top: 1px solid var(--line);
  color: var(--muted);
}

.site-footer p {
  margin: 0;
}

.site-footer p:first-child {
  color: var(--ink);
  font-weight: 850;
}

@media (max-width: 1060px) {
  .hero-section,
  .intro-section,
  .api-section {
    grid-template-columns: 1fr;
  }

  .path-board {
    min-height: 520px;
  }

  .use-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  .site-header {
    min-height: auto;
    flex-wrap: wrap;
    padding-top: 16px;
    padding-bottom: 16px;
  }

  .nav-links {
    order: 3;
    width: 100%;
    justify-content: space-between;
  }

  .nav-action {
    padding: 9px 13px;
  }

  .hero-section {
    min-height: auto;
    padding-top: 52px;
  }

  .hero-actions,
  .site-footer {
    align-items: stretch;
    flex-direction: column;
  }

  .button {
    width: 100%;
  }

  .path-board {
    min-height: 460px;
  }

  .thought-cloud span:nth-child(n + 6) {
    display: none;
  }

  .path-line {
    top: 118px;
    right: 34px;
    width: 58%;
    height: 230px;
  }

  .answer-panel {
    right: 22px;
    bottom: 22px;
    left: 22px;
  }

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

  .step {
    min-height: auto;
  }

  .step h3 {
    margin-top: 32px;
  }

  .api-row {
    display: block;
  }

  .api-row strong {
    display: block;
    margin-top: 6px;
    text-align: left;
  }
}