:root {
  --bg: #f7f8fb;
  --surface: #ffffff;
  --surface-strong: #eef7f5;
  --ink: #151718;
  --muted: #5d666f;
  --line: #d9dee6;
  --accent: #0f766e;
  --accent-strong: #0b5f59;
  --accent-soft: #d9f4ef;
  --warm: #b54708;
  --danger: #b42318;
  --shadow: 0 18px 50px rgba(26, 38, 54, 0.14);
}

* {
  box-sizing: border-box;
}

html {
  background: var(--bg);
  color: var(--ink);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  letter-spacing: 0;
}

body {
  margin: 0;
  min-width: 320px;
}

a {
  color: inherit;
}

.site-header,
.site-footer {
  align-items: center;
  display: flex;
  gap: 24px;
  justify-content: space-between;
  margin: 0 auto;
  max-width: 1120px;
  padding: 18px 24px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(247, 248, 251, 0.9);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(217, 222, 230, 0.8);
}

.brand {
  align-items: center;
  display: inline-flex;
  gap: 10px;
  font-weight: 760;
  text-decoration: none;
}

.brand img {
  border-radius: 8px;
  box-shadow: 0 8px 22px rgba(15, 118, 110, 0.18);
}

nav {
  align-items: center;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  justify-content: flex-end;
}

nav a {
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.95rem;
  font-weight: 650;
  padding: 8px 12px;
  text-decoration: none;
}

nav a:hover,
nav a[aria-current="page"] {
  background: var(--surface);
  color: var(--ink);
}

.hero,
.band,
.privacy-summary,
.policy-main {
  margin: 0 auto;
  max-width: 1120px;
  padding-left: 24px;
  padding-right: 24px;
}

.hero {
  align-items: center;
  display: grid;
  gap: 54px;
  grid-template-columns: minmax(0, 0.94fr) minmax(360px, 1.06fr);
  padding-bottom: 52px;
  padding-top: 74px;
}

.hero h1,
.policy-hero h1 {
  font-size: clamp(3.4rem, 9vw, 7.8rem);
  line-height: 0.92;
  margin: 0;
}

.hero-copy {
  max-width: 620px;
}

.eyebrow {
  color: var(--accent-strong);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0;
  margin: 0 0 12px;
  text-transform: uppercase;
}

.lead {
  color: var(--muted);
  font-size: clamp(1.12rem, 2vw, 1.35rem);
  line-height: 1.55;
  margin: 24px 0 0;
}

.actions {
  align-items: center;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

.button {
  align-items: center;
  border: 1px solid var(--line);
  border-radius: 8px;
  display: inline-flex;
  font-weight: 760;
  justify-content: center;
  min-height: 44px;
  padding: 11px 16px;
  text-decoration: none;
}

.button.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #ffffff;
}

.button:not(.primary):not(.disabled) {
  background: var(--surface);
}

.button:hover:not(.disabled) {
  transform: translateY(-1px);
}

.button.disabled {
  color: #7a828a;
  cursor: default;
}

.product-visual {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
  min-height: 392px;
  overflow: hidden;
}

.visual-toolbar {
  align-items: center;
  background: #151718;
  color: #ffffff;
  display: flex;
  gap: 8px;
  min-height: 48px;
  padding: 0 16px;
}

.visual-toolbar span {
  border-radius: 999px;
  display: block;
  height: 10px;
  width: 10px;
}

.visual-toolbar span:nth-child(1) {
  background: #f04438;
}

.visual-toolbar span:nth-child(2) {
  background: #fdb022;
}

.visual-toolbar span:nth-child(3) {
  background: #12b76a;
}

.visual-toolbar strong {
  font-size: 0.88rem;
  font-weight: 700;
  margin-left: 8px;
}

.visual-body {
  display: grid;
  gap: 18px;
  grid-template-columns: minmax(0, 1.2fr) minmax(128px, 0.7fr);
  padding: 22px;
}

.paper-pane {
  background:
    linear-gradient(90deg, rgba(15, 118, 110, 0.05), transparent 45%),
    var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  min-height: 300px;
  padding: 34px 26px;
  position: relative;
}

.paper-line {
  align-items: center;
  display: flex;
  gap: 10px;
  height: 12px;
  margin: 0 0 18px;
}

.paper-line::before,
.paper-line::after,
.paper-line span {
  background: #cdd5df;
  border-radius: 999px;
  content: "";
  display: block;
  height: 12px;
  min-width: 0;
}

.paper-line::before {
  flex: 1 1 72%;
}

.paper-line::after,
.paper-line span {
  flex: 1 1 24%;
}

.paper-line.wide::before {
  flex-basis: 88%;
}

.paper-line.medium::before {
  flex-basis: 62%;
}

.paper-line.short::before {
  flex-basis: 44%;
}

mark {
  background: var(--accent-soft);
  border: 1px solid rgba(15, 118, 110, 0.25);
  border-radius: 6px;
  color: var(--accent-strong);
  font-weight: 800;
  padding: 2px 7px;
}

.citation-popover {
  background: #151718;
  border-radius: 8px;
  bottom: 42px;
  box-shadow: 0 18px 32px rgba(21, 23, 24, 0.24);
  color: #ffffff;
  display: grid;
  gap: 7px;
  left: 52px;
  max-width: calc(100% - 82px);
  padding: 14px;
  position: absolute;
}

.citation-popover span {
  color: #cbd5e1;
}

.citation-popover small {
  color: #7dd3c7;
  font-weight: 760;
}

.graph-pane {
  background:
    radial-gradient(circle at 50% 38%, rgba(15, 118, 110, 0.1), transparent 34%),
    var(--surface-strong);
  border: 1px solid #c9e8e1;
  border-radius: 8px;
  min-height: 300px;
  position: relative;
}

.node,
.edge {
  display: block;
  position: absolute;
}

.node {
  background: #ffffff;
  border: 3px solid var(--accent);
  border-radius: 999px;
  box-shadow: 0 10px 22px rgba(15, 118, 110, 0.14);
  height: 42px;
  width: 42px;
}

.node.root {
  left: 50%;
  top: 38%;
  transform: translate(-50%, -50%);
}

.node.one {
  border-color: var(--warm);
  left: 16%;
  top: 66%;
}

.node.two {
  border-color: var(--danger);
  right: 18%;
  top: 68%;
}

.edge {
  background: #93a3b5;
  height: 3px;
  left: 34%;
  top: 58%;
  transform: rotate(34deg);
  transform-origin: left center;
  width: 64px;
}

.edge.e2 {
  left: 52%;
  transform: rotate(-34deg);
}

.band,
.privacy-summary,
.policy-section {
  border-top: 1px solid var(--line);
}

.band {
  padding-bottom: 58px;
  padding-top: 50px;
}

.section-heading {
  max-width: 620px;
}

h2 {
  font-size: clamp(1.8rem, 4vw, 3rem);
  line-height: 1.05;
  margin: 0;
}

.feature-grid {
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin-top: 28px;
}

.feature {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 22px;
}

.feature h3 {
  font-size: 1.04rem;
  margin: 0 0 10px;
}

.feature p,
.privacy-summary p,
.policy-section p,
.policy-section li,
.policy-hero p {
  color: var(--muted);
  line-height: 1.65;
}

.feature p {
  margin: 0;
}

.privacy-summary {
  display: grid;
  gap: 22px;
  grid-template-columns: minmax(240px, 0.7fr) minmax(0, 1fr) auto;
  padding-bottom: 56px;
  padding-top: 46px;
}

.privacy-summary p {
  margin: 0;
}

.text-link {
  align-self: center;
  color: var(--accent-strong);
  font-weight: 800;
  text-decoration-thickness: 2px;
  text-underline-offset: 4px;
  white-space: nowrap;
}

.policy-main {
  max-width: 920px;
  padding-bottom: 42px;
}

.policy-hero {
  padding-bottom: 40px;
  padding-top: 64px;
}

.policy-hero h1 {
  font-size: clamp(3rem, 8vw, 6.4rem);
}

.policy-section {
  padding-bottom: 34px;
  padding-top: 34px;
}

.policy-section h2 {
  font-size: clamp(1.45rem, 3vw, 2.15rem);
  margin-bottom: 16px;
}

.policy-section p {
  margin: 0 0 16px;
}

.policy-section ul {
  display: grid;
  gap: 12px;
  margin: 0;
  padding-left: 22px;
}

.policy-section strong {
  color: var(--ink);
}

.policy-section code {
  background: #eef1f6;
  border: 1px solid #d8dee8;
  border-radius: 6px;
  color: #303846;
  font-size: 0.95em;
  padding: 2px 5px;
}

.policy-section a,
.site-footer a {
  color: var(--accent-strong);
  font-weight: 720;
  text-decoration-thickness: 2px;
  text-underline-offset: 4px;
}

.site-footer {
  border-top: 1px solid var(--line);
  color: var(--muted);
  flex-wrap: wrap;
  font-size: 0.94rem;
  padding-bottom: 28px;
  padding-top: 28px;
}

.guide-figure {
  margin: 26px 0 10px;
}

.guide-figure img {
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: 0 12px 32px rgba(26, 38, 54, 0.12);
  display: block;
  height: auto;
  max-width: 100%;
}

.guide-figure figcaption {
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.5;
  margin-top: 10px;
}

.guide-figure.narrow img {
  max-width: 560px;
}

.guide-figure-row {
  align-items: start;
  display: grid;
  gap: 16px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.guide-callout {
  background: var(--accent-soft);
  border: 1px solid rgba(15, 118, 110, 0.28);
  border-radius: 8px;
  margin: 20px 0;
  padding: 16px 18px;
}

.guide-callout p {
  color: var(--ink);
  margin: 0;
}

.key-note {
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 4px solid var(--warm);
  border-radius: 8px;
  margin: 20px 0;
  padding: 16px 18px;
}

.key-note p {
  margin: 0;
}

@media (max-width: 700px) {
  .guide-figure-row {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 860px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
    gap: 12px;
  }

  nav {
    justify-content: flex-start;
  }

  .hero {
    grid-template-columns: 1fr;
    padding-top: 52px;
  }

  .product-visual {
    min-height: 340px;
  }

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

  .text-link {
    justify-self: start;
  }
}

@media (max-width: 560px) {
  .site-header,
  .site-footer,
  .hero,
  .band,
  .privacy-summary,
  .policy-main {
    padding-left: 16px;
    padding-right: 16px;
  }

  .brand img {
    height: 34px;
    width: 34px;
  }

  nav a {
    padding: 7px 9px;
  }

  .actions {
    align-items: stretch;
    flex-direction: column;
  }

  .button {
    width: 100%;
  }

  .visual-body {
    grid-template-columns: 1fr;
    padding: 16px;
  }

  .graph-pane {
    min-height: 160px;
  }

  .paper-pane {
    min-height: 240px;
    padding: 26px 18px;
  }

  .citation-popover {
    left: 24px;
    max-width: calc(100% - 48px);
  }
}