:root {
  color-scheme: light;
  --bg: #f8fafc;
  --panel: #ffffff;
  --panel-soft: #f1f7f9;
  --text: #172033;
  --muted: #64748b;
  --line: #dbe5eb;
  --blue: #2563eb;
  --blue-dark: #1d4ed8;
  --teal: #0f766e;
  --green-soft: #dff3ed;
  --shadow: 0 20px 60px rgba(15, 23, 42, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    "Microsoft YaHei", "PingFang SC", sans-serif;
  line-height: 1.6;
}

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  gap: 28px;
  min-height: 68px;
  padding: 0 40px;
  border-bottom: 1px solid rgba(219, 229, 235, 0.82);
  background: rgba(248, 250, 252, 0.88);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 15px;
  font-weight: 700;
}

.brand-mark {
  display: inline-grid;
  width: 30px;
  height: 30px;
  place-items: center;
  border-radius: 8px;
  background: linear-gradient(135deg, #1d4ed8, #0f766e);
  color: #fff;
}

.top-nav {
  display: flex;
  align-items: center;
  gap: 22px;
  margin-left: auto;
  color: var(--muted);
  font-size: 14px;
}

.top-nav a:hover,
.nav-action:hover {
  color: var(--blue);
}

.nav-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 36px;
  padding: 0 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: #334155;
  font-size: 14px;
  font-weight: 600;
  background: #fff;
}

.section-shell {
  width: min(1120px, calc(100% - 48px));
  margin: 0 auto;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(420px, 0.95fr);
  gap: 68px;
  align-items: center;
  min-height: calc(100vh - 68px);
  padding: 74px 0 64px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--teal);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

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

h1 {
  max-width: 720px;
  margin-bottom: 22px;
  font-size: clamp(44px, 7vw, 76px);
  line-height: 1.02;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 14px;
  font-size: clamp(28px, 4vw, 42px);
  line-height: 1.14;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 8px;
  font-size: 18px;
  line-height: 1.35;
}

.hero-lead {
  max-width: 680px;
  margin-bottom: 16px;
  color: #334155;
  font-size: 20px;
  line-height: 1.7;
}

.hero-support,
.workflow-copy p,
.preview-panel p,
.open-grid p,
.feature p,
.step p,
.doctor-note p {
  color: var(--muted);
}

.hero-support {
  max-width: 650px;
  margin-bottom: 30px;
  font-size: 17px;
}

.hero-actions,
.inline-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 18px;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 700;
}

.button-primary {
  background: var(--blue);
  color: #fff;
  box-shadow: 0 12px 30px rgba(37, 99, 235, 0.18);
}

.button-primary:hover {
  background: var(--blue-dark);
}

.button-secondary {
  border: 1px solid var(--line);
  background: #fff;
  color: #1f2937;
}

.button-secondary:hover {
  border-color: #b8c7d2;
  background: #f8fafc;
}

.hero-visual {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 16px;
}

.hero-visual::before {
  position: absolute;
  inset: 48px -18px -18px 42px;
  z-index: -1;
  border-radius: 28px;
  background: linear-gradient(135deg, rgba(223, 243, 237, 0.85), rgba(219, 234, 254, 0.88));
  content: "";
}

.visual-card {
  overflow: hidden;
  border: 1px solid rgba(219, 229, 235, 0.92);
  border-radius: 14px;
  background: var(--panel);
  box-shadow: var(--shadow);
}

.visual-card img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.visual-card span {
  display: block;
  padding: 12px 14px;
  color: #334155;
  font-size: 14px;
  font-weight: 700;
}

.visual-card-large img {
  aspect-ratio: 16 / 11;
}

.visual-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.info-band,
.workflow,
.preview-panel,
.open-source {
  padding: 88px 0;
}

.section-heading {
  max-width: 740px;
  margin-bottom: 30px;
}

.feature-grid,
.open-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.feature,
.step,
.open-grid article,
.doctor-note {
  border: 1px solid var(--line);
  border-radius: 14px;
  background: var(--panel);
  box-shadow: 0 14px 40px rgba(15, 23, 42, 0.045);
}

.feature,
.step,
.open-grid article {
  padding: 24px;
}

.feature-index {
  display: inline-block;
  margin-bottom: 34px;
  color: var(--blue);
  font-size: 13px;
  font-weight: 800;
}

.workflow {
  display: grid;
  grid-template-columns: minmax(0, 0.72fr) minmax(0, 1.28fr);
  gap: 38px;
  align-items: start;
}

.workflow-copy {
  position: sticky;
  top: 104px;
}

.steps {
  display: grid;
  gap: 16px;
}

.step {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  column-gap: 18px;
}

.step span {
  display: inline-grid;
  width: 42px;
  height: 42px;
  place-items: center;
  border-radius: 10px;
  background: var(--green-soft);
  color: var(--teal);
  font-weight: 800;
}

.step p {
  grid-column: 2;
  margin-bottom: 0;
}

.preview-panel {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 0.54fr);
  gap: 28px;
  align-items: center;
  padding-top: 44px;
}

.preview-panel > div:first-child {
  padding: 34px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: linear-gradient(180deg, #fff, #f7fbff);
  box-shadow: var(--shadow);
}

.doctor-note {
  display: grid;
  grid-template-columns: 118px minmax(0, 1fr);
  gap: 18px;
  align-items: center;
  padding: 20px;
}

.doctor-note img {
  width: 118px;
  height: 118px;
  object-fit: contain;
}

.doctor-note p {
  margin-bottom: 0;
}

.open-source {
  padding-bottom: 110px;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding: 26px 40px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 14px;
}

@media (max-width: 900px) {
  .site-header {
    padding: 0 20px;
  }

  .top-nav {
    display: none;
  }

  .hero,
  .workflow,
  .preview-panel {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: 0;
    padding-top: 52px;
  }

  .workflow-copy {
    position: static;
  }

  .feature-grid,
  .open-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 560px) {
  .section-shell {
    width: min(100% - 28px, 1120px);
  }

  .site-header {
    min-height: 62px;
  }

  .brand {
    font-size: 14px;
  }

  .nav-action {
    display: none;
  }

  h1 {
    font-size: 42px;
  }

  .hero-lead {
    font-size: 18px;
  }

  .visual-grid,
  .doctor-note {
    grid-template-columns: 1fr;
  }

  .doctor-note img {
    width: 96px;
    height: 96px;
  }

  .step {
    grid-template-columns: 1fr;
  }

  .step p {
    grid-column: auto;
  }

  .site-footer {
    flex-direction: column;
    padding: 24px 20px;
  }
}