:root {
  color-scheme: light;
  --bg: #f7fbff;
  --surface: #ffffff;
  --surface-soft: #eef7ff;
  --ink: #172033;
  --text: #25324a;
  --muted: #66728a;
  --subtle: #8d98aa;
  --line: rgba(33, 56, 96, 0.13);
  --blue: #188bf5;
  --cyan: #36d4ee;
  --violet: #8367f5;
  --mint: #18b99a;
  --amber: #f4a62a;
  --rose: #ec5f86;
  --shadow: 0 24px 70px rgba(27, 74, 140, 0.15);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

[id] {
  scroll-margin-top: 5.5rem;
}

body {
  margin: 0;
  background:
    linear-gradient(135deg, rgba(54, 212, 238, 0.16), transparent 30rem),
    linear-gradient(180deg, #ffffff 0%, var(--bg) 42rem, #ffffff 100%);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", "YuGothic", sans-serif;
  letter-spacing: 0;
}

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

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

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

h1,
h2,
h3 {
  color: var(--ink);
  overflow-wrap: anywhere;
}

h1 {
  font-size: 2.55rem;
  line-height: 1.05;
}

h2 {
  font-size: 2rem;
  line-height: 1.18;
}

h3 {
  font-size: 1.08rem;
  line-height: 1.35;
}

p {
  overflow-wrap: anywhere;
}

code {
  border: 1px solid rgba(24, 139, 245, 0.18);
  border-radius: 6px;
  background: rgba(24, 139, 245, 0.07);
  color: #155eab;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 0.92em;
}

.site-header,
.hero,
.section,
.app-store-cta,
.site-footer {
  width: min(100% - 2rem, 74rem);
  margin: 0 auto;
}

/* Language switching: hide the inactive language. */
[data-lang="ja"] [lang="en"],
[data-lang="en"] [lang="ja"] {
  display: none !important;
}

.lang-toggle {
  flex: 0 0 auto;
  min-height: 2.4rem;
  padding: 0 0.75rem;
  border: 1px solid rgba(24, 139, 245, 0.24);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.78);
  color: var(--blue);
  font-family: inherit;
  font-size: 0.82rem;
  font-weight: 850;
  cursor: pointer;
  transition: color 160ms ease, border-color 160ms ease;
}

.lang-toggle:hover {
  border-color: rgba(131, 103, 245, 0.4);
  color: var(--violet);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.9rem 0;
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  min-width: 0;
  color: var(--ink);
  font-weight: 850;
}

.brand img {
  flex: 0 0 auto;
  border-radius: 8px;
  box-shadow: 0 10px 24px rgba(24, 139, 245, 0.16);
}

.brand span {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.nav-links {
  display: none;
  align-items: center;
  gap: 1.35rem;
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 750;
}

.nav-links a,
.trust-item a {
  transition: color 160ms ease;
}

.nav-links a:hover,
.trust-item a:hover {
  color: var(--blue);
}

.header-cta,
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 2.75rem;
  border-radius: 8px;
  font-weight: 850;
  white-space: nowrap;
}

.header-cta {
  flex: 0 0 auto;
  padding: 0 1rem;
  border: 1px solid rgba(24, 139, 245, 0.24);
  background: rgba(255, 255, 255, 0.78);
  color: var(--blue);
  font-size: 0.86rem;
  box-shadow: 0 12px 32px rgba(24, 139, 245, 0.12);
}

.hero {
  display: grid;
  gap: 2.5rem;
  align-items: center;
  padding: 3.2rem 0 4rem;
}

.hero-copy {
  max-width: 45rem;
}

.eyebrow {
  margin-bottom: 0.85rem;
  color: var(--mint);
  font-size: 0.76rem;
  font-weight: 900;
  text-transform: uppercase;
}

.hero-lead,
.section-heading p,
.ai-copy p,
.app-store-cta p,
.trust-item p,
.problem-card p,
.step-item p,
.feature-card p {
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.78;
}

.hero-lead {
  margin-top: 1.1rem;
  max-width: 40rem;
  font-size: 1.08rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.6rem;
}

.button {
  padding: 0 1.1rem;
  border: 1px solid transparent;
  font-size: 0.95rem;
}

.button.primary {
  background: linear-gradient(135deg, var(--blue), var(--violet));
  color: #ffffff;
  box-shadow: 0 16px 38px rgba(24, 139, 245, 0.28);
}

.button.secondary {
  border-color: var(--line);
  background: rgba(255, 255, 255, 0.78);
  color: var(--text);
}

.signal-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin: 1.45rem 0 0;
  padding: 0;
  list-style: none;
}

.signal-list li {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  color: var(--muted);
  font-size: 0.84rem;
  font-weight: 800;
}

.signal-list li::before {
  width: 0.5rem;
  height: 0.5rem;
  border-radius: 999px;
  background: var(--cyan);
  content: "";
}

.signal-list li:nth-child(2)::before {
  background: var(--violet);
}

.signal-list li:nth-child(3)::before {
  background: var(--amber);
}

.signal-list li:nth-child(4)::before {
  background: var(--mint);
}

.hero-visual {
  position: relative;
  justify-self: center;
  width: min(100%, 32rem);
  min-height: 35rem;
}

.hero-icon {
  position: absolute;
  top: 0;
  left: 0.5rem;
  z-index: 3;
  width: 7rem;
}

.hero-icon img {
  border-radius: 24%;
  box-shadow:
    0 0 0 1px rgba(24, 139, 245, 0.08),
    0 24px 64px rgba(24, 139, 245, 0.22);
}

.phone-shot {
  overflow: hidden;
  aspect-ratio: 1206 / 2622;
  border: 1px solid rgba(33, 56, 96, 0.16);
  border-radius: 2.3rem;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.phone-shot img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.phone-shot-main {
  position: absolute;
  top: 2.5rem;
  left: 4.3rem;
  width: 18.2rem;
}

.phone-shot-secondary {
  position: absolute;
  right: 0.25rem;
  bottom: 0;
  width: 12.2rem;
  box-shadow: 0 22px 56px rgba(66, 54, 142, 0.18);
}

.section {
  padding: 4.3rem 0;
}

.section-heading {
  max-width: 45rem;
  margin-bottom: 2rem;
}

.section-heading.compact {
  max-width: 38rem;
}

.section-heading h2 {
  margin-bottom: 0.85rem;
}

.problem-grid,
.trust-grid,
.use-case-grid {
  display: grid;
  gap: 1rem;
}

.problem-card,
.trust-item,
.feature-card,
.step-item,
.use-case-grid article {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.82);
  box-shadow: 0 14px 36px rgba(27, 74, 140, 0.08);
}

.problem-card {
  padding: 1.25rem;
}

.problem-card > span {
  display: inline-block;
  margin-bottom: 0.9rem;
  color: var(--blue);
  font-size: 0.78rem;
  font-weight: 900;
}

.problem-card h3 {
  margin-bottom: 0.6rem;
}

.solution-section {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(90deg, rgba(54, 212, 238, 0.08), transparent 48%),
    linear-gradient(270deg, rgba(131, 103, 245, 0.08), transparent 56%);
  width: 100%;
}

.solution-section > * {
  width: min(100% - 2rem, 74rem);
  margin-right: auto;
  margin-left: auto;
}

.step-list {
  display: grid;
  gap: 0.9rem;
}

.step-item {
  display: grid;
  grid-template-columns: 2.6rem minmax(0, 1fr);
  gap: 0.9rem;
  align-items: start;
  padding: 1rem;
}

.step-item > span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.35rem;
  height: 2.35rem;
  border-radius: 8px;
  background: linear-gradient(135deg, rgba(24, 139, 245, 0.14), rgba(54, 212, 238, 0.14));
  color: var(--blue);
  font-weight: 900;
}

.step-item h3 {
  margin-bottom: 0.35rem;
}

.feature-grid {
  display: grid;
  gap: 1rem;
}

.feature-card {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 8.2rem;
  gap: 1rem;
  min-height: 18rem;
  overflow: hidden;
  padding: 1.2rem 1.2rem 0;
}

.feature-copy {
  align-self: start;
  padding-bottom: 1.2rem;
}

.feature-mark {
  display: block;
  width: 1.8rem;
  height: 0.32rem;
  margin-bottom: 0.9rem;
  border-radius: 999px;
  background: var(--blue);
}

.feature-mark.mint {
  background: var(--mint);
}

.feature-mark.violet {
  background: var(--violet);
}

.feature-mark.amber {
  background: var(--amber);
}

.feature-card h3 {
  margin-bottom: 0.55rem;
}

.feature-shot {
  align-self: end;
  overflow: hidden;
  height: 16.8rem;
  border: 1px solid rgba(33, 56, 96, 0.12);
  border-radius: 1.4rem 1.4rem 0 0;
  background: #ffffff;
  box-shadow: 0 18px 38px rgba(27, 74, 140, 0.12);
}

.feature-shot img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top center;
}

.ai-section {
  display: grid;
  gap: 2rem;
  align-items: center;
}

.ai-copy {
  max-width: 43rem;
}

.ai-copy h2 {
  margin-bottom: 0.85rem;
}

.use-case-grid {
  margin-top: 1.5rem;
}

.use-case-grid article {
  padding: 0.95rem 1rem;
  color: var(--text);
  font-size: 0.95rem;
  font-weight: 750;
  line-height: 1.55;
}

.use-case-grid article::before {
  display: inline-block;
  width: 0.52rem;
  height: 0.52rem;
  margin-right: 0.55rem;
  border-radius: 999px;
  background: var(--cyan);
  content: "";
}

.chat-shot {
  width: min(100%, 18.4rem);
  justify-self: center;
}

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

.trust-grid {
  margin-top: 1.7rem;
}

.trust-item {
  padding: 1.2rem;
}

.trust-item h3 {
  margin-bottom: 0.55rem;
}

.trust-item a {
  color: var(--blue);
  font-weight: 800;
  text-decoration: underline;
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
}

.app-store-cta {
  display: grid;
  gap: 1.5rem;
  align-items: center;
  margin-bottom: 4rem;
  padding: 1.5rem;
  border: 1px solid rgba(24, 139, 245, 0.2);
  border-radius: 8px;
  background:
    linear-gradient(135deg, rgba(24, 139, 245, 0.12), transparent 42%),
    linear-gradient(315deg, rgba(54, 212, 238, 0.12), transparent 48%),
    #ffffff;
  box-shadow: var(--shadow);
}

.app-store-cta h2 {
  margin-bottom: 0.75rem;
}

.app-store-cta .button {
  justify-self: start;
}

.site-footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem 1.5rem;
  padding: 2rem 0 2.4rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.9rem;
}

.footer-brand {
  font-size: 0.95rem;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.2rem;
  font-size: 0.88rem;
  font-weight: 750;
}

.footer-links a {
  transition: color 160ms ease;
}

.footer-links a:hover {
  color: var(--blue);
}

.footer-copy {
  color: var(--subtle);
  font-size: 0.85rem;
}

/* Policy / support pages */
.policy {
  width: min(100% - 2rem, 52rem);
  margin: 0 auto;
  padding: 2.6rem 0 3.6rem;
}

.policy h1 {
  margin-bottom: 0.5rem;
  font-size: 2.2rem;
}

.policy .updated {
  margin-bottom: 1.6rem;
  color: var(--muted);
  font-size: 0.95rem;
}

.policy section {
  margin-top: 2.1rem;
}

.policy h2 {
  margin-bottom: 0.7rem;
  font-size: 1.42rem;
}

.policy h3 {
  margin: 1.5rem 0 0.5rem;
  font-size: 1.06rem;
}

.policy p,
.policy li {
  color: var(--text);
  font-size: 1rem;
  line-height: 1.8;
}

.policy p + p {
  margin-top: 0.7rem;
}

.policy ul {
  margin: 0.7rem 0 0;
  padding-left: 1.25rem;
}

.policy li {
  margin-bottom: 0.45rem;
}

.policy a {
  color: var(--blue);
  text-decoration: underline;
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
}

@media (min-width: 680px) {
  h1 {
    font-size: 3.3rem;
  }

  .nav-links {
    display: flex;
  }

  .problem-grid,
  .trust-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

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

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

  .app-store-cta {
    grid-template-columns: minmax(0, 1fr) auto;
    padding: 2rem;
  }

  .app-store-cta .button {
    justify-self: end;
  }
}

@media (min-width: 920px) {
  h1 {
    font-size: 4.1rem;
  }

  .hero {
    grid-template-columns: minmax(0, 1.05fr) minmax(25rem, 0.95fr);
    padding-top: 4.2rem;
  }

  .hero-visual {
    min-height: 39rem;
  }

  .phone-shot-main {
    width: 20rem;
  }

  .phone-shot-secondary {
    width: 13.4rem;
  }

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

  .feature-card {
    grid-template-columns: minmax(0, 1fr) 9.2rem;
  }

  .feature-shot {
    height: 18.5rem;
  }

  .ai-section {
    grid-template-columns: minmax(0, 1fr) 20rem;
  }

  .chat-shot {
    width: 19rem;
  }
}

@media (max-width: 479px) {
  .site-header,
  .hero,
  .section,
  .app-store-cta,
  .site-footer {
    width: min(100% - 1.25rem, 74rem);
  }

  .brand span {
    max-width: 8.5rem;
  }

  .header-cta {
    padding: 0 0.8rem;
    font-size: 0.8rem;
  }

  .hero {
    padding-top: 2.4rem;
  }

  .hero-visual {
    min-height: 31.5rem;
  }

  .hero-icon {
    left: 0;
    width: 5.8rem;
  }

  .phone-shot-main {
    left: 2.7rem;
    width: 15.5rem;
  }

  .phone-shot-secondary {
    width: 10rem;
  }

  .feature-card {
    grid-template-columns: minmax(0, 1fr) 7rem;
    min-height: 16rem;
    padding: 1rem 1rem 0;
  }

  .feature-shot {
    height: 14.5rem;
  }
}