:root {
  --bg: #13161b;
  --bg-elev: #1a1e24;
  --line: #2a2f38;
  --text: #f4f4f5;
  --muted: #9a9ea6;
  --pill: #ffffff;
  --pill-text: #0b0b0b;
}

* {
  box-sizing: border-box;
}

html {
  scroll-padding-top: 88px;
}

@media (prefers-reduced-motion: no-preference) {
  html {
    scroll-behavior: smooth;
  }
}

html,
body {
  margin: 0;
  padding: 0;
  background: radial-gradient(circle at 70% 20%, #2a2f38 0%, var(--bg) 46%);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans JP", sans-serif;
}

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

.header {
  position: sticky;
  top: 0;
  z-index: 20;
  height: 76px;
  padding: 0 28px;
  border-bottom: 1px solid var(--line);
  background: rgba(19, 22, 27, 0.76);
  backdrop-filter: blur(10px);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-weight: 800;
  letter-spacing: 0.24em;
  font-size: 0.95rem;
}

.nav {
  display: flex;
  gap: 28px;
  color: #aab0b8;
  font-size: 0.95rem;
}

.order-pill {
  background: var(--pill);
  color: var(--pill-text);
  padding: 10px 22px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 0.95rem;
}

main {
  max-width: 1180px;
  margin: 0 auto;
  padding: 20px 24px 90px;
}

.hero {
  position: relative;
  overflow: hidden;
  min-height: calc(100vh - 96px);
  display: flex;
  align-items: center;
  padding: 80px 0;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: transparent;
  z-index: 1;
  pointer-events: none;
}

.hero-bg-product {
  position: absolute;
  right: -100px;
  top: 50%;
  transform: translate(1cm, -50%);
  width: min(82vw, 980px);
  opacity: 0.44;
  filter: none;
  z-index: 0;
}

.hero-left {
  position: relative;
  z-index: 2;
  max-width: 720px;
}

.eyebrow {
  color: #818792;
  letter-spacing: 0.28em;
  font-size: 0.72rem;
}

h1 {
  font-size: clamp(2.5rem, 6vw, 4.4rem);
  line-height: 1.05;
  margin: 12px 0 18px;
}

.lead {
  color: var(--muted);
  line-height: 1.8;
  max-width: 580px;
}

.hero-cta {
  margin-top: 28px;
  display: flex;
  gap: 12px;
}

.btn {
  border-radius: 999px;
  padding: 12px 24px;
  border: 1px solid #2d3138;
  font-weight: 700;
  display: inline-block;
}

.btn-primary {
  background: #fff;
  color: #0b0b0b;
  border-color: #fff;
}

.btn-ghost {
  background: transparent;
  color: #d7d9df;
}

section {
  padding: 94px 0;
  border-top: 1px solid var(--line);
}

.center {
  text-align: center;
}

h2 {
  margin: 12px 0 14px;
  text-align: center;
  font-size: clamp(2rem, 4vw, 3.3rem);
}

.section-lead {
  text-align: center;
  color: var(--muted);
  margin: 0 auto 32px;
  max-width: 700px;
  line-height: 1.7;
}

.features-top__title {
  text-align: center;
  margin: 0 0 10px;
}

.features-top__lead {
  text-align: center;
  margin: 0 auto 40px;
  max-width: 700px;
}

.features-split {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: clamp(24px, 4vw, 48px);
  align-items: start;
}

.features-split__media {
  margin: 0;
  margin-left: 2cm;
  max-width: 380px;
  width: 100%;
  justify-self: start;
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid #2a303a;
  background: #1a1e24;
}

.features-split__media img {
  display: block;
  width: 100%;
  height: auto;
}

.features-split__cards {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.card {
  background: linear-gradient(180deg, #1c2027 0%, #151920 100%);
  border: 1px solid #2a303a;
  border-radius: 16px;
  padding: 26px 22px;
}

.card h3 {
  margin: 0 0 8px;
  font-size: 1.35rem;
}

.card p {
  margin: 0;
  color: var(--muted);
  line-height: 1.75;
}

.how-content {
  margin: 32px auto 0;
  max-width: 1180px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(260px, 400px);
  gap: 28px;
  align-items: start;
}

.how-content__video {
  border-radius: 14px;
  overflow: hidden;
  border: 1px solid #2a303a;
  background: #0c0e12;
  position: sticky;
  top: 92px;
}

.how-content__player {
  display: block;
  width: 100%;
  height: auto;
}

.how-content ol {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: hole-step;
  display: grid;
  gap: 22px;
}

.how-content li {
  position: relative;
  padding-left: 58px;
}

.how-content li::before {
  counter-increment: hole-step;
  content: counter(hole-step, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 2px;
  color: #2f3540;
  font-size: 2rem;
  font-weight: 700;
}

.how-content h3 {
  margin: 0 0 6px;
  font-size: 1.55rem;
}

.how-content p {
  margin: 0;
  color: var(--muted);
  line-height: 1.75;
}

.price {
  text-align: center;
}

.price p {
  color: var(--muted);
}

.recommend-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
  margin-top: 34px;
}

.faq .accordion {
  max-width: 880px;
  margin: 24px auto 0;
  display: grid;
  gap: 12px;
}

.faq details {
  border: 1px solid #303744;
  border-radius: 12px;
  background: #181c23;
  padding: 18px 20px;
  overflow: hidden;
}

.faq summary {
  cursor: pointer;
  font-weight: 600;
  list-style: none;
  position: relative;
  padding-right: 1.75rem;
}

.faq summary::-webkit-details-marker {
  display: none;
}

.faq summary::after {
  content: "";
  position: absolute;
  right: 0.15rem;
  top: 0.42em;
  width: 0.45em;
  height: 0.45em;
  border-right: 2px solid #8b919d;
  border-bottom: 2px solid #8b919d;
  transform: rotate(45deg);
  transition: transform 0.45s cubic-bezier(0.32, 0.72, 0, 1);
}

.faq details[open] summary::after {
  transform: rotate(-135deg);
  top: 0.55em;
}

@media (prefers-reduced-motion: reduce) {
  .faq-answer {
    transition: none;
  }

  .faq summary::after {
    transition: none;
  }
}

/* UA の closed details 子要素の display:none を上書きし、高さアニメーションを有効にする */
.faq details .faq-answer {
  display: grid !important;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.45s cubic-bezier(0.32, 0.72, 0, 1);
}

.faq details[open] .faq-answer {
  grid-template-rows: 1fr;
}

.faq-answer__inner {
  min-height: 0;
  overflow: hidden;
}

.faq details p {
  color: var(--muted);
  margin: 14px 0 2px;
  line-height: 1.75;
}

.faq details a {
  text-decoration: underline;
}

.contact {
  text-align: center;
}

.footer {
  border-top: 1px solid var(--line);
  padding: 26px 24px 40px;
  display: flex;
  max-width: 1180px;
  margin: 0 auto;
  justify-content: space-between;
  gap: 20px;
  color: #8d939f;
  font-size: 0.92rem;
}

.footer-links {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  justify-content: flex-end;
  align-items: center;
}

.footer-sns,
.footer-legal {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
  align-items: center;
}

.footer-sns a {
  text-decoration: underline;
  text-decoration-color: rgba(141, 147, 159, 0.45);
  text-underline-offset: 3px;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.footer-sns a.sns-icon {
  width: 38px;
  height: 38px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 999px;
  border: 1px solid rgba(141, 147, 159, 0.25);
  background: rgba(19, 22, 27, 0.25);
  text-decoration: none;
  transition: transform 0.18s ease, border-color 0.18s ease, background 0.18s ease, color 0.18s ease;
}

.footer-sns a.sns-icon svg {
  width: 20px;
  height: 20px;
  display: block;
}

.footer-sns a.sns-icon:hover {
  transform: translateY(-1px);
  border-color: rgba(141, 147, 159, 0.5);
  background: rgba(26, 30, 36, 0.55);
  color: #d7d9df;
}

.footer-sns a.sns-icon:focus-visible {
  outline: 2px solid rgba(255, 255, 255, 0.65);
  outline-offset: 3px;
}

.footer-legal a {
  text-decoration: underline;
  text-decoration-color: rgba(141, 147, 159, 0.35);
  text-underline-offset: 3px;
}

@media (max-width: 980px) {
  .nav {
    display: none;
  }

  .hero {
    min-height: auto;
    padding-top: 32px;
  }

  .hero-bg-product {
    right: -48px;
    width: min(98vw, 720px);
    opacity: 0.38;
  }

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

  .how-content {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .how-content__video {
    position: static;
    max-width: 420px;
    margin-left: auto;
    margin-right: auto;
    order: 2;
  }

  .how-content ol {
    order: 1;
  }

  .features-top__lead {
    margin-bottom: 28px;
  }

  .features-split {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .features-split__media {
    max-width: 320px;
    justify-self: center;
    margin-left: 0;
  }
}