/* PayNode
   構成は Tailwind CSS / Vercel のトップページ、余白は Carbon のスペーシングスケール
   （2 / 4 / 8 / 12 / 16 / 24 / 32 / 40 / 48 / 64 / 96）に合わせている。
   色はモノクロ。濃い面はコマンドブロックだけ。 */

:root {
  color-scheme: light;

  --bg: #ffffff;
  --bg-subtle: #fafafa;
  --ink: #0a0a0a;
  --ink-2: #52525b;
  --ink-3: #71717a;
  --line: #e4e4e7;
  --line-strong: #d4d4d8;
  --focus: #2563eb;

  --container: 1120px;
  --font: "Yu Gothic UI", "Yu Gothic", "Hiragino Kaku Gothic ProN", Meiryo,
    system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: "Cascadia Mono", Consolas, ui-monospace, monospace;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: inherit;
}

:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 2px;
  border-radius: 4px;
}

.container {
  width: min(100% - 48px, var(--container));
  margin-inline: auto;
}

.skip {
  position: absolute;
  top: -56px;
  left: 16px;
  z-index: 20;
  padding: 8px 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--bg);
  text-decoration: none;
}

.skip:focus {
  top: 12px;
}

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

.header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--line);
}

.header__inner {
  display: flex;
  align-items: center;
  gap: 24px;
  height: 64px;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: -0.01em;
  text-decoration: none;
}

.logo img {
  display: block;
  border-radius: 5px;
}

.nav {
  display: flex;
  gap: 24px;
  margin-left: auto;
  font-size: 14px;
}

.nav a {
  color: var(--ink-2);
  text-decoration: none;
}

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

/* --------------------------------------------------------------- buttons */

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 44px;
  padding: 0 20px;
  border: 1px solid transparent;
  border-radius: 8px;
  background: var(--ink);
  color: #fff;
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: opacity 0.15s ease;
}

.button:hover {
  opacity: 0.85;
}

.button--secondary {
  background: var(--bg);
  border-color: var(--line-strong);
  color: var(--ink);
}

.button--secondary:hover {
  background: var(--bg-subtle);
  opacity: 1;
}

.button--small {
  height: 36px;
  padding: 0 14px;
  font-size: 13px;
}

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

.hero {
  padding: 96px 0 64px;
  text-align: center;
}

.hero h1 {
  max-width: 760px;
  margin-inline: auto;
  font-size: clamp(2rem, 4.6vw, 3rem);
  font-weight: 700;
  line-height: 1.22;
  letter-spacing: -0.02em;
}

.hero__lead {
  max-width: 620px;
  margin: 20px auto 0;
  color: var(--ink-2);
  font-size: 1.0625rem;
  line-height: 1.8;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-top: 32px;
}


/* --------------------------------------------------------------- snippet */

#install,
#features,
#steps {
  scroll-margin-top: 88px;
}

.snippet {
  max-width: 720px;
  margin: 48px auto 0;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--bg-subtle);
  overflow: hidden;
  text-align: left;
}

.snippet__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 10px 16px;
  border-bottom: 1px solid var(--line);
  font-size: 13px;
  color: var(--ink-3);
}

.snippet__copy {
  padding: 4px 10px;
  border: 1px solid var(--line-strong);
  border-radius: 6px;
  background: var(--bg);
  color: var(--ink-2);
  font: inherit;
  font-size: 12px;
  cursor: pointer;
}

.snippet__copy:hover {
  color: var(--ink);
}

.snippet__body {
  margin: 0;
  padding: 20px;
  background: #0a0a0a;
  color: #e4e4e7;
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.7;
  overflow-x: auto;
  white-space: pre;
}

.snippet__body code {
  font: inherit;
}

.snippet__note {
  padding: 12px 16px;
  border-top: 1px solid var(--line);
  color: var(--ink-3);
  font-size: 13px;
}

/* --------------------------------------------------------------- section */

.section {
  padding: 64px 0;
  border-top: 1px solid var(--line);
}

.section__title {
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 32px;
  margin-top: 32px;
}

.item__icon {
  width: 24px;
  height: 24px;
  color: var(--ink-2);
}

.item h3 {
  margin-top: 16px;
  font-size: 0.9375rem;
  font-weight: 600;
}

.item p {
  margin-top: 8px;
  color: var(--ink-2);
  font-size: 0.875rem;
  line-height: 1.8;
}

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

.steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 32px;
  margin: 32px 0 0;
  padding: 0;
  list-style: none;
}

.steps__num {
  display: grid;
  place-items: center;
  width: 24px;
  height: 24px;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  font-size: 12px;
  font-weight: 600;
  color: var(--ink-2);
}

.steps h3 {
  margin-top: 16px;
  font-size: 0.9375rem;
  font-weight: 600;
}

.steps p {
  margin-top: 8px;
  color: var(--ink-2);
  font-size: 0.875rem;
  line-height: 1.8;
}

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

.footer {
  border-top: 1px solid var(--line);
  padding: 32px 0;
  color: var(--ink-3);
  font-size: 13px;
}

.footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.footer__nav {
  display: flex;
  gap: 20px;
}

.footer__nav a {
  color: var(--ink-3);
  text-decoration: none;
}

.footer__nav a:hover {
  color: var(--ink);
  text-decoration: underline;
}

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

@media (max-width: 860px) {
  .grid,
  .steps {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .nav {
    display: none;
  }

  .header__inner {
    justify-content: space-between;
  }
}

@media (max-width: 560px) {
  .container {
    width: min(100% - 32px, var(--container));
  }

  .hero {
    padding: 56px 0 48px;
  }

  .hero h1 {
    font-size: 1.5rem;
  }

  .hero__lead {
    font-size: 0.9375rem;
  }

  .hero__actions .button {
    flex: 1 1 auto;
  }

  .snippet {
    margin-top: 32px;
  }

  .snippet__body {
    font-size: 12px;
    white-space: pre-wrap;
    overflow-wrap: anywhere;
  }

  .section {
    padding: 48px 0;
  }

  .footer__inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation: none !important;
    transition-duration: 0.001ms !important;
  }
}