/* ─── Reset & Base ─────────────────────────────────────────── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --white:        #FFFFFF;
  --black:        #111111;
  --gray-light:   #F6F6F4;
  --gray-border:  #E2E2E0;
  --gray-text:    #555555;
  --gray-muted:   #999999;
  --lavender:     #9D8EC4;
  --mint:         #62BAB3;
  --font-serif:   'Noto Serif JP', serif;
  --font-sans:    'Noto Sans JP', sans-serif;
  --max-w:        680px;
  --pad-h:        40px;
  --section-v:    120px;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  background: var(--white);
  color: var(--black);
  font-family: var(--font-sans);
  font-weight: 300;
  line-height: 1.9;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--pad-h);
}

/* ─── Header ────────────────────────────────────────────────── */
#site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 100;
  padding: 22px var(--pad-h);
  background: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s;
}

#site-header.scrolled {
  border-bottom-color: var(--gray-border);
}

.nav-inner {
  max-width: calc(var(--max-w) + var(--pad-h) * 2);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--black);
}

.logo-img {
  height: 56px;
  width: auto;
}

.nav-cta {
  font-size: 12px;
  font-weight: 300;
  letter-spacing: 0.08em;
  color: var(--black);
  text-decoration: none;
  border-bottom: 1px solid var(--mint);
  padding-bottom: 1px;
  transition: opacity 0.2s;
}

.nav-cta:hover { opacity: 0.4; }

/* ─── Hero ──────────────────────────────────────────────────── */
.hero {
  min-height: 100svh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 120px 32px 80px;
}

.hero-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 28px;
}

.hero-copy {
  font-family: var(--font-serif);
  font-weight: 200;
  font-size: clamp(30px, 5.5vw, 52px);
  letter-spacing: 0.1em;
  line-height: 1.45;
  color: var(--black);
}

.hero-sub {
  font-size: 14px;
  font-weight: 300;
  color: var(--gray-text);
  letter-spacing: 0.06em;
  line-height: 1.9;
  white-space: nowrap;
}

.scroll-hint {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  margin-top: 48px;
  color: var(--lavender);
  text-decoration: none;
  font-size: 11px;
  letter-spacing: 0.15em;
  transition: opacity 0.2s;
  animation: nudge 2.4s ease-in-out infinite;
}

.scroll-hint:hover { opacity: 0.4; }

@keyframes nudge {
  0%, 100% { transform: translateY(0); }
  50%       { transform: translateY(6px); }
}

/* ─── VMV ───────────────────────────────────────────────────── */
.vmv {
  padding: var(--section-v) 0;
  border-top: 1px solid var(--gray-border);
}

.vmv-list {
  display: flex;
  flex-direction: column;
  gap: 52px;
}

.vmv-item {
  display: grid;
  grid-template-columns: 88px 1fr;
  gap: 24px;
  align-items: baseline;
}

.vmv-item dt {
  font-size: 13px;
  font-weight: 300;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--lavender);
  padding-top: 5px;
}

.vmv-item dd {
  font-family: var(--font-serif);
  font-weight: 300;
  font-size: clamp(18px, 2.4vw, 21px);
  line-height: 1.7;
  letter-spacing: 0.05em;
}

/* ─── Shared section block ──────────────────────────────────── */
.section-block {
  padding: var(--section-v) 0;
  border-top: 1px solid var(--gray-border);
}

.section-heading {
  font-family: var(--font-serif);
  font-weight: 300;
  font-size: clamp(20px, 3.2vw, 30px);
  line-height: 1.55;
  letter-spacing: 0.06em;
  margin-bottom: 52px;
}

.section-label {
  font-size: 12px;
  font-weight: 300;
  letter-spacing: 0.12em;
  color: var(--lavender);
  margin-bottom: 44px;
}

/* ─── Body text ─────────────────────────────────────────────── */
.body-text p {
  font-size: 15px;
  font-weight: 300;
  line-height: 2.1;
  color: #3a3a3a;
  letter-spacing: 0.04em;
  margin-bottom: 28px;
}

.body-text p:last-child { margin-bottom: 0; }

.body-text p.text-note {
  font-size: 13.5px;
  color: var(--gray-text);
  border-left: 2px solid var(--mint);
  padding-left: 20px;
  line-height: 2.0;
}

.body-text p.text-italic {
  font-family: var(--font-serif);
  font-weight: 200;
  font-style: italic;
  font-size: 14px;
  color: var(--gray-text);
}

/* ─── Seahorse traits ───────────────────────────────────────── */
.traits {
  margin: 36px 0;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.traits-item {
  display: grid;
  grid-template-columns: 148px 1fr;
  gap: 16px;
  align-items: baseline;
}

.traits-item dt {
  font-family: var(--font-serif);
  font-weight: 400;
  font-size: 14px;
  letter-spacing: 0.04em;
  color: var(--mint);
}

.traits-item dd {
  font-size: 14px;
  font-weight: 300;
  color: #3a3a3a;
  line-height: 1.9;
}

/* ─── Technology (light bg) ─────────────────────────────────── */
.technology {
  background: var(--gray-light);
}

/* ─── Join us / Form ────────────────────────────────────────── */
.contact-form {
  margin-top: 52px;
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.form-group label {
  font-size: 11px;
  font-weight: 300;
  letter-spacing: 0.15em;
  color: var(--gray-muted);
}

.form-group input,
.form-group textarea {
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: 300;
  color: var(--black);
  background: transparent;
  border: none;
  border-bottom: 1px solid var(--gray-border);
  padding: 10px 0;
  outline: none;
  width: 100%;
  transition: border-color 0.25s;
  letter-spacing: 0.03em;
}

.form-group input:focus,
.form-group textarea:focus {
  border-bottom-color: var(--black);
}

.form-group textarea {
  resize: vertical;
  min-height: 110px;
  line-height: 1.9;
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: #c0c0c0;
  font-weight: 300;
}

.btn-submit {
  align-self: flex-start;
  margin-top: 8px;
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 300;
  letter-spacing: 0.12em;
  color: var(--white);
  background: var(--mint);
  border: none;
  padding: 15px 40px;
  cursor: pointer;
  transition: opacity 0.2s;
}

.btn-submit:hover      { opacity: 0.65; }
.btn-submit:disabled   { opacity: 0.4; cursor: default; }

.btn-link {
  display: inline-block;
  text-decoration: none;
  margin-top: 32px;
}

.form-success {
  margin-top: 40px;
  font-family: var(--font-serif);
  font-weight: 300;
  font-size: 17px;
  color: var(--gray-text);
  line-height: 1.9;
  letter-spacing: 0.04em;
}

/* ─── Footer ────────────────────────────────────────────────── */
footer {
  border-top: 1px solid var(--gray-border);
  padding: 44px 0;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-serif);
  font-weight: 200;
  font-size: 15px;
  letter-spacing: 0.06em;
  color: var(--black);
}

.logo-img-small {
  height: 32px;
  width: auto;
}

.footer-copy {
  font-size: 11px;
  font-weight: 300;
  color: var(--gray-muted);
  letter-spacing: 0.06em;
}

/* ─── Fade-in on scroll ─────────────────────────────────────── */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.9s ease, transform 0.9s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ─── Responsive ────────────────────────────────────────────── */
@media (max-width: 600px) {
  :root {
    --section-v: 80px;
    --pad-h:     24px;
  }

  #site-header {
    padding: 18px var(--pad-h);
  }

  .hero-sub {
    white-space: normal;
  }

  .vmv-item {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .vmv-item dt { padding-top: 0; }

  .traits-item {
    grid-template-columns: 1fr;
    gap: 4px;
  }

  .footer-inner {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }
}