:root {
  --bg: #0b0c10;
  --bg-soft: #14161d;
  --surface: rgba(255, 255, 255, 0.06);
  --surface-strong: rgba(255, 255, 255, 0.10);
  --border: rgba(255, 255, 255, 0.10);
  --border-strong: rgba(255, 255, 255, 0.18);
  --text: #ffffff;
  --text-soft: rgba(255, 255, 255, 0.78);
  --muted: rgba(255, 255, 255, 0.55);
  --accent: #ff9a76; /* peach */
  --accent-2: #ff6fb1; /* pink */
  --accent-3: #6ec5ff; /* cyan */
  --accent-4: #b88dff; /* lavender */
  --gradient: linear-gradient(
    135deg,
    #ff9a76 0%,
    #ff6fb1 28%,
    #b88dff 60%,
    #6ec5ff 100%
  );
  --max: 1180px;
  --radius: 20px;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Inter", "Noto Sans JP", -apple-system, BlinkMacSystemFont, sans-serif;
  -webkit-font-smoothing: antialiased;
  line-height: 1.6;
  scroll-behavior: smooth;
}

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

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

h1,
h2,
h3 {
  margin: 0;
  letter-spacing: -0.02em;
  line-height: 1.18;
}

p {
  margin: 0;
}

/* ============== HERO ============== */
.hero {
  position: relative;
  min-height: 92vh;
  padding: 24px 32px 96px;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-bg img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.7;
  filter: saturate(1.05);
}

.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    rgba(11, 12, 16, 0.1) 0%,
    rgba(11, 12, 16, 0.55) 60%,
    rgba(11, 12, 16, 0.9) 100%
  );
  z-index: 1;
}

.nav,
.hero-inner {
  position: relative;
  z-index: 2;
  max-width: var(--max);
  margin: 0 auto;
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 0 64px;
}

.nav-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 17px;
  font-weight: 700;
  letter-spacing: 0.01em;
}

.brand-mark {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  object-fit: cover;
  box-shadow: 0 0 24px rgba(255, 111, 177, 0.35);
}

.nav-cta {
  padding: 10px 18px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.10);
  border: 1px solid rgba(255, 255, 255, 0.18);
  font-size: 13px;
  font-weight: 600;
  backdrop-filter: blur(12px);
  transition: background 160ms ease;
}

.nav-cta:hover {
  background: rgba(255, 255, 255, 0.18);
}

.hero-inner {
  padding-top: 4vh;
  max-width: 920px;
}

.eyebrow,
.section-eyebrow {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.16em;
  color: var(--muted);
  margin-bottom: 18px;
  text-transform: uppercase;
}

.section-eyebrow.accent {
  background: var(--gradient);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero h1 {
  font-size: clamp(40px, 7.5vw, 88px);
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
}

.hero-sub {
  font-size: clamp(15px, 1.4vw, 19px);
  color: var(--text-soft);
  max-width: 640px;
  margin-bottom: 36px;
}

.hero-actions {
  display: inline-flex;
  flex-wrap: wrap;
  gap: 14px;
  align-items: center;
}

.btn-primary,
.btn-ghost {
  display: inline-flex;
  flex-direction: column;
  align-items: flex-start;
  padding: 14px 22px;
  border-radius: 14px;
  font-weight: 700;
  font-size: 15px;
  transition: transform 160ms ease, box-shadow 160ms ease, background 160ms ease;
}

.btn-primary {
  background: var(--gradient);
  color: #0b0c10;
  box-shadow: 0 12px 40px rgba(255, 111, 177, 0.35);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 16px 48px rgba(255, 111, 177, 0.5);
}

.btn-meta {
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.02em;
  opacity: 0.7;
  margin-top: 2px;
}

.btn-ghost {
  border: 1px solid var(--border-strong);
  background: rgba(255, 255, 255, 0.05);
  backdrop-filter: blur(12px);
  flex-direction: row;
  gap: 4px;
}

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.12);
}

/* ============== SHOWCASE ============== */
.showcase {
  position: relative;
  padding: 80px 32px 100px;
  background: var(--bg);
}

.showcase::before {
  content: "";
  position: absolute;
  inset: -10% 5% auto 5%;
  height: 60%;
  background: var(--gradient);
  filter: blur(160px);
  opacity: 0.22;
  z-index: 0;
  pointer-events: none;
}

.showcase-inner {
  position: relative;
  z-index: 1;
  max-width: 1080px;
  margin: 0 auto;
  text-align: center;
}

.showcase-frame {
  position: relative;
  border-radius: 22px;
  overflow: hidden;
  border: 1px solid var(--border-strong);
  background: var(--surface);
  box-shadow:
    0 30px 80px rgba(0, 0, 0, 0.55),
    0 0 0 1px rgba(255, 255, 255, 0.04) inset;
  margin-bottom: 28px;
}

.showcase-frame img {
  width: 100%;
  display: block;
}

.showcase-caption {
  font-size: 14px;
  color: var(--text-soft);
  line-height: 1.8;
}

.showcase-caption strong {
  color: var(--text);
  font-weight: 700;
}

/* ============== SECTIONS ============== */
.features,
.migration,
.howto,
.download {
  position: relative;
  padding: 120px 32px;
}

.features,
.howto {
  background: var(--bg);
}

.migration {
  background: linear-gradient(
    180deg,
    var(--bg) 0%,
    var(--bg-soft) 50%,
    var(--bg) 100%
  );
}

.download {
  position: relative;
  overflow: hidden;
}

.download::before {
  content: "";
  position: absolute;
  inset: -20% -10% auto -10%;
  height: 70%;
  background: var(--gradient);
  filter: blur(140px);
  opacity: 0.28;
  z-index: 0;
  pointer-events: none;
}

.section-title {
  font-size: clamp(28px, 4.4vw, 52px);
  font-weight: 800;
  letter-spacing: -0.025em;
  max-width: 880px;
  margin: 0 auto 64px;
  text-align: center;
}

/* feature grid */
.feature-grid {
  max-width: var(--max);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
}

.feature-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 24px 28px;
  backdrop-filter: blur(12px);
  transition: transform 200ms ease, border-color 200ms ease, background 200ms ease;
}

.feature-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-strong);
  background: var(--surface-strong);
}

.feature-card img {
  width: 100%;
  aspect-ratio: 1 / 1;
  border-radius: 14px;
  object-fit: cover;
  margin-bottom: 18px;
}

.feature-card h3 {
  font-size: 19px;
  font-weight: 700;
  margin-bottom: 10px;
}

.feature-card p {
  font-size: 14px;
  color: var(--text-soft);
  line-height: 1.7;
}

/* Wide variant: 2-column grid with larger images and dual sub-features */
.feature-grid-wide {
  grid-template-columns: repeat(auto-fit, minmax(420px, 1fr));
  gap: 28px;
}

.feature-card-wide {
  padding: 24px 28px 32px;
}

.feature-card-wide img {
  aspect-ratio: 16 / 9;
  margin-bottom: 24px;
}

.feature-card-wide .feature-subgroup {
  padding-top: 18px;
  margin-top: 18px;
  border-top: 1px solid var(--border);
}

.feature-card-wide .feature-subgroup:first-of-type {
  padding-top: 0;
  margin-top: 0;
  border-top: none;
}

.feature-card-wide .feature-subgroup h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.feature-card-wide .feature-subgroup p {
  margin: 0;
}

/* migration */
.migration-inner {
  max-width: var(--max);
  margin: 0 auto;
  text-align: center;
}

.migration-lead {
  max-width: 720px;
  margin: -32px auto 56px;
  color: var(--text-soft);
  font-size: 16px;
}

.migration-steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
  text-align: left;
}

.step {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 24px;
  backdrop-filter: blur(12px);
}

.step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--gradient);
  color: #0b0c10;
  font-weight: 800;
  font-size: 16px;
  margin-bottom: 14px;
}

.step strong {
  display: block;
  font-size: 17px;
  margin-bottom: 6px;
}

.step p {
  font-size: 13.5px;
  color: var(--text-soft);
}

/* howto */
.howto-list {
  max-width: 820px;
  margin: 0 auto;
  list-style: none;
  padding: 0;
  display: grid;
  gap: 16px;
  counter-reset: howto;
}

.howto-list li {
  position: relative;
  counter-increment: howto;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 28px 28px 88px;
  backdrop-filter: blur(12px);
}

.howto-list li::before {
  content: counter(howto, decimal-leading-zero);
  position: absolute;
  left: 24px;
  top: 24px;
  font-size: 28px;
  font-weight: 800;
  background: var(--gradient);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  letter-spacing: -0.02em;
}

.howto-list strong {
  display: block;
  font-size: 18px;
  margin-bottom: 6px;
}

.howto-list p {
  font-size: 14px;
  color: var(--text-soft);
}

/* download */
.download-inner {
  position: relative;
  z-index: 1;
  max-width: 760px;
  margin: 0 auto;
  text-align: center;
}

.download-lead {
  color: var(--text-soft);
  margin-bottom: 40px;
}

.download-buttons {
  display: inline-flex;
  flex-wrap: wrap;
  gap: 16px;
  justify-content: center;
  margin-bottom: 32px;
}

.btn-primary.big,
.btn-ghost.big {
  padding: 18px 28px;
  border-radius: 16px;
  min-width: 240px;
}

.btn-label {
  font-size: 16px;
  font-weight: 700;
}

.sys-req {
  list-style: none;
  padding: 0;
  margin: 0;
  font-size: 13px;
  color: var(--muted);
  display: inline-flex;
  flex-wrap: wrap;
  gap: 16px;
  justify-content: center;
}

.sys-req li {
  position: relative;
  padding-left: 14px;
}

.sys-req li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--gradient);
}

/* footer */
.footer {
  background: var(--bg);
  border-top: 1px solid var(--border);
  padding: 40px 32px;
}

.footer-inner {
  max-width: var(--max);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 15px;
}

.footer-note {
  font-size: 13px;
  color: var(--muted);
}

@media (max-width: 720px) {
  .hero {
    padding: 16px 20px 80px;
    min-height: 100vh;
  }
  .nav {
    padding: 8px 0 40px;
  }
  .features,
  .migration,
  .howto,
  .download {
    padding: 80px 20px;
  }
  .feature-card img {
    aspect-ratio: 1.4 / 1;
  }
  .howto-list li {
    padding: 80px 24px 24px;
  }
  .howto-list li::before {
    left: 24px;
    top: 24px;
  }
}