:root {
  color-scheme: light;
  --cloud: #ffffff;
  --aqua: #c0e6ff;
  --sea: #4da2ff;
  --ocean: #011829;
  --deep-ocean: #030f1c;
  --text: #04111f;
  --muted: #506477;
  --line: rgba(1, 24, 41, 0.14);
  --panel: rgba(255, 255, 255, 0.78);
  --shadow: 0 24px 80px rgba(1, 24, 41, 0.16);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  background:
    linear-gradient(180deg, rgba(192, 230, 255, 0.96) 0%, rgba(255, 255, 255, 0.98) 38%, #f7fbff 100%);
}

button,
a {
  -webkit-tap-highlight-color: transparent;
}

button {
  font: inherit;
}

a {
  color: inherit;
}

.site-shell {
  min-height: 100vh;
}

.topbar,
main,
.footer {
  width: min(1160px, calc(100vw - 32px));
  margin: 0 auto;
}

.topbar {
  min-height: 78px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-size: 18px;
  font-weight: 780;
  letter-spacing: 0;
}

.brand-mark,
.drop-mark {
  position: relative;
  display: inline-grid;
  place-items: center;
  background: var(--sea);
}

.brand-mark {
  width: 34px;
  height: 34px;
  border-radius: 10px;
  box-shadow: 0 12px 24px rgba(77, 162, 255, 0.3);
}

.brand-mark::before,
.drop-mark::before {
  content: "";
  width: 46%;
  height: 62%;
  border-radius: 56% 56% 60% 60%;
  background: var(--cloud);
  transform: rotate(45deg);
}

.nav {
  display: flex;
  align-items: center;
  gap: 20px;
  color: rgba(4, 17, 31, 0.72);
  font-size: 14px;
  font-weight: 720;
}

.nav a {
  text-decoration: none;
}

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

.nav-cta {
  min-height: 38px;
  display: inline-flex;
  align-items: center;
  border-radius: 8px;
  padding: 0 14px;
  color: var(--cloud) !important;
  background: var(--ocean);
}

.hero {
  min-height: calc(100vh - 78px);
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(340px, 460px);
  gap: 56px;
  align-items: center;
  padding: 36px 0 80px;
}

.eyebrow,
.section-kicker {
  margin: 0;
  color: var(--sea);
  font-size: 13px;
  font-weight: 820;
  letter-spacing: 0;
  text-transform: uppercase;
}

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

h1 {
  max-width: 760px;
  margin-bottom: 22px;
  color: var(--ocean);
  font-size: clamp(46px, 7vw, 86px);
  line-height: 0.98;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 14px;
  color: var(--ocean);
  font-size: clamp(30px, 4vw, 52px);
  line-height: 1.04;
  letter-spacing: 0;
}

.hero-lede,
.split-section > div > p,
.boundary-copy p {
  max-width: 660px;
  color: var(--muted);
  font-size: 18px;
  line-height: 1.65;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.primary-btn,
.secondary-btn {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 8px;
  padding: 0 18px;
  text-decoration: none;
  font-weight: 780;
}

.primary-btn {
  color: var(--cloud);
  background: var(--ocean);
  box-shadow: 0 18px 40px rgba(1, 24, 41, 0.22);
}

.secondary-btn {
  border: 1px solid var(--line);
  color: var(--ocean);
  background: rgba(255, 255, 255, 0.62);
}

.signal-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 34px;
}

.signal-row span {
  min-height: 42px;
  display: inline-flex;
  align-items: center;
  gap: 7px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0 12px;
  color: var(--muted);
  background: rgba(255, 255, 255, 0.58);
}

.signal-row strong {
  color: var(--ocean);
}

.hero-visual {
  display: grid;
  place-items: center;
}

.checkout-card {
  width: min(100%, 430px);
  border: 1px solid rgba(77, 162, 255, 0.32);
  border-radius: 8px;
  padding: 18px;
  background: rgba(255, 255, 255, 0.88);
  box-shadow: var(--shadow);
}

.checkout-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
}

.checkout-head span,
.amount-panel span,
.receipt-box span {
  display: block;
  color: var(--muted);
  font-size: 13px;
  font-weight: 720;
}

.checkout-head strong {
  display: block;
  margin-top: 4px;
  color: var(--ocean);
  font-size: 18px;
}

.checkout-head small {
  min-height: 28px;
  display: inline-flex;
  align-items: center;
  border-radius: 999px;
  padding: 0 10px;
  color: var(--ocean);
  background: var(--aqua);
  font-weight: 820;
}

.amount-panel {
  margin-top: 28px;
  border-radius: 8px;
  padding: 20px;
  color: var(--cloud);
  background: var(--ocean);
}

.amount-panel strong {
  display: block;
  margin-top: 8px;
  font-size: 46px;
  line-height: 1;
}

.amount-panel small {
  display: block;
  margin-top: 10px;
  color: var(--aqua);
}

.login-row {
  width: 100%;
  min-height: 72px;
  margin-top: 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 0 14px;
  text-align: left;
  color: var(--text);
  background: var(--cloud);
  cursor: default;
}

.drop-mark {
  width: 40px;
  height: 40px;
  flex: 0 0 40px;
  border-radius: 50%;
}

.login-row strong,
.login-row small {
  display: block;
}

.login-row small {
  margin-top: 4px;
  color: var(--muted);
}

.receipt-box {
  margin-top: 14px;
  border: 1px solid rgba(77, 162, 255, 0.25);
  border-radius: 8px;
  padding: 14px;
  background: #f4fbff;
}

.receipt-box code {
  display: block;
  margin-top: 6px;
  color: var(--ocean);
  font-size: 14px;
  overflow-wrap: anywhere;
}

.principles {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
  padding: 26px 0 86px;
}

.principles article,
.code-card,
.flow-list,
.boundary-grid div {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: 0 14px 48px rgba(1, 24, 41, 0.08);
}

.principles article {
  padding: 18px;
}

.principles article > span {
  color: var(--sea);
  font-weight: 860;
}

.principles h2 {
  margin: 34px 0 10px;
  font-size: 20px;
  line-height: 1.15;
}

.principles p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.55;
}

.split-section,
.boundary-section {
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(340px, 1fr);
  gap: 44px;
  align-items: start;
  padding: 82px 0;
  border-top: 1px solid var(--line);
}

.flow-list {
  list-style: none;
  margin: 0;
  padding: 8px;
}

.flow-list li {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 14px;
  padding: 16px;
}

.flow-list li + li {
  border-top: 1px solid var(--line);
}

.flow-list li > span {
  color: var(--sea);
  font-weight: 860;
}

.flow-list strong {
  color: var(--ocean);
}

.flow-list p {
  margin: 5px 0 0;
  color: var(--muted);
  line-height: 1.52;
}

.developer-section {
  padding: 84px 0;
  border-top: 1px solid var(--line);
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 30px;
  margin-bottom: 26px;
}

.section-heading h2 {
  max-width: 720px;
  margin-bottom: 0;
}

.developer-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.code-card {
  overflow: hidden;
  background: var(--deep-ocean);
  color: var(--cloud);
}

.code-head {
  min-height: 50px;
  border-bottom: 1px solid rgba(192, 230, 255, 0.16);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 0 16px;
  color: var(--aqua);
  font-weight: 780;
}

.code-head button {
  min-height: 32px;
  border: 1px solid rgba(192, 230, 255, 0.34);
  border-radius: 8px;
  padding: 0 10px;
  color: var(--cloud);
  background: rgba(77, 162, 255, 0.18);
  cursor: pointer;
}

pre {
  margin: 0;
  padding: 18px;
  overflow-x: auto;
}

code {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-size: 13px;
  line-height: 1.65;
}

.boundary-grid {
  display: grid;
  gap: 12px;
}

.boundary-grid div {
  padding: 18px;
}

.boundary-grid strong,
.boundary-grid span {
  display: block;
}

.boundary-grid strong {
  color: var(--ocean);
  font-size: 18px;
}

.boundary-grid span {
  margin-top: 6px;
  color: var(--muted);
  line-height: 1.52;
}

.footer {
  min-height: 90px;
  border-top: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  color: var(--muted);
  font-size: 14px;
}

.footer span:first-child {
  color: var(--ocean);
  font-weight: 820;
}

@media (max-width: 860px) {
  .topbar {
    align-items: flex-start;
    flex-direction: column;
    padding: 18px 0;
  }

  .nav {
    width: 100%;
    overflow-x: auto;
    gap: 14px;
    padding-bottom: 2px;
  }

  .hero,
  .split-section,
  .boundary-section,
  .developer-grid {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
    gap: 34px;
    padding-top: 30px;
  }

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

  .section-heading {
    align-items: flex-start;
    flex-direction: column;
  }
}

@media (max-width: 560px) {
  .topbar,
  main,
  .footer {
    width: min(100vw - 24px, 1160px);
  }

  h1 {
    font-size: 44px;
  }

  h2 {
    font-size: 32px;
  }

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

  .amount-panel strong {
    font-size: 38px;
  }

  .footer {
    align-items: flex-start;
    flex-direction: column;
    justify-content: center;
  }
}