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

:root {
  --color-bg: #0c0c14;
  --color-surface: rgba(255, 255, 255, 0.04);
  --color-surface-hover: rgba(255, 255, 255, 0.08);
  --color-border: rgba(255, 255, 255, 0.08);
  --color-text: #e8e8f0;
  --color-text-muted: #8888a0;
  --color-text-dim: #555566;
  --color-accent: #a78bfa;
  --color-accent-soft: rgba(167, 139, 250, 0.15);
  --color-rose: #f9a8d4;
  --color-rose-soft: rgba(249, 168, 212, 0.12);
  --color-teal: #5eead4;
  --color-teal-soft: rgba(94, 234, 212, 0.12);
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --font-family: 'Noto Sans JP', -apple-system, BlinkMacSystemFont, 'Hiragino Sans', sans-serif;
}

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

body {
  font-family: var(--font-family);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

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

/* ===== Background Orbs ===== */
.page-bg {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  overflow: hidden;
}

.bg-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(100px);
  opacity: 0.35;
}

.bg-orb--1 {
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, var(--color-accent) 0%, transparent 70%);
  top: -150px;
  right: -100px;
  animation: float-1 20s ease-in-out infinite;
}

.bg-orb--2 {
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, var(--color-rose) 0%, transparent 70%);
  bottom: 20%;
  left: -100px;
  animation: float-2 25s ease-in-out infinite;
}

.bg-orb--3 {
  width: 350px;
  height: 350px;
  background: radial-gradient(circle, var(--color-teal) 0%, transparent 70%);
  top: 50%;
  right: 10%;
  animation: float-3 18s ease-in-out infinite;
}

@keyframes float-1 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(-40px, 30px) scale(1.05); }
  66% { transform: translate(20px, -20px) scale(0.95); }
}

@keyframes float-2 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(50px, -40px) scale(1.1); }
}

@keyframes float-3 {
  0%, 100% { transform: translate(0, 0); }
  40% { transform: translate(-30px, 20px); }
  80% { transform: translate(15px, -30px); }
}

/* ===== Header ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  background: rgba(12, 12, 20, 0.7);
  border-bottom: 1px solid var(--color-border);
}

.header__inner {
  max-width: 960px;
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.header__logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 1.1rem;
  transition: opacity 0.2s;
}

.header__logo:hover {
  opacity: 0.8;
}

.header__logo-icon {
  font-size: 1.4rem;
}

.header__nav {
  display: flex;
  gap: 24px;
}

.header__link {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  transition: color 0.2s;
  position: relative;
}

.header__link::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-accent);
  border-radius: 1px;
  transition: width 0.3s ease;
}

.header__link:hover {
  color: var(--color-text);
}

.header__link:hover::after {
  width: 100%;
}

.header__link--active {
  color: var(--color-accent);
}

.header__link--active::after {
  width: 100%;
}

/* ===== Hero ===== */
.hero {
  position: relative;
  z-index: 1;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 120px 24px 80px;
  gap: 60px;
  max-width: 1080px;
  margin: 0 auto;
}

.hero__content {
  flex: 1;
  max-width: 480px;
}

.hero__tagline {
  font-size: 0.9rem;
  color: var(--color-accent);
  font-weight: 500;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
  opacity: 0;
  animation: fadeInUp 0.8s ease 0.2s forwards;
}

.hero__title {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 24px;
  background: linear-gradient(135deg, var(--color-text) 0%, var(--color-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  opacity: 0;
  animation: fadeInUp 0.8s ease 0.4s forwards;
}

.hero__description {
  font-size: 0.95rem;
  color: var(--color-text-muted);
  line-height: 1.9;
  margin-bottom: 32px;
  opacity: 0;
  animation: fadeInUp 0.8s ease 0.6s forwards;
}

.hero__badges {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  opacity: 0;
  animation: fadeInUp 0.8s ease 0.8s forwards;
}

.hero__badge {
  display: inline-block;
  padding: 6px 16px;
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 500;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  backdrop-filter: blur(8px);
}

/* ===== Hero Cards ===== */
.hero__cards {
  position: relative;
  width: 260px;
  height: 340px;
  flex-shrink: 0;
  opacity: 0;
  animation: fadeIn 1s ease 1s forwards;
}

.hero__card {
  position: absolute;
  width: 220px;
  height: 300px;
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  backdrop-filter: blur(16px);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  transition: transform 0.5s ease;
}

.hero__card--back {
  top: 0;
  left: 0;
  transform: rotate(-8deg) scale(0.9);
  opacity: 0.5;
}

.hero__card--mid {
  top: 10px;
  left: 20px;
  transform: rotate(-3deg) scale(0.95);
  opacity: 0.7;
}

.hero__card--front {
  top: 20px;
  left: 40px;
  transform: rotate(2deg);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
  animation: card-float 6s ease-in-out infinite 1.5s;
}

.hero__card-emoji {
  font-size: 4rem;
  margin-bottom: 16px;
}

.hero__card-actions {
  display: flex;
  gap: 12px;
  font-size: 0.7rem;
  color: var(--color-text-dim);
}

.hero__action--left { color: var(--color-rose); }
.hero__action--up { color: var(--color-teal); }
.hero__action--right { color: var(--color-accent); }

@keyframes card-float {
  0%, 100% { transform: rotate(2deg) translateY(0); }
  50% { transform: rotate(2deg) translateY(-8px); }
}

/* ===== Features ===== */
.features {
  position: relative;
  z-index: 1;
  padding: 0 24px 80px;
  max-width: 960px;
  margin: 0 auto;
}

.features__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.feature-card {
  padding: 32px 24px;
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  backdrop-filter: blur(12px);
  text-align: center;
  transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-4px);
  border-color: rgba(167, 139, 250, 0.2);
  box-shadow: 0 12px 40px rgba(167, 139, 250, 0.08);
}

.feature-card__icon {
  font-size: 2.5rem;
  margin-bottom: 16px;
}

.feature-card__title {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.feature-card__text {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  line-height: 1.7;
}

/* ===== Links Section ===== */
.links-section {
  position: relative;
  z-index: 1;
  padding: 0 24px 100px;
  max-width: 720px;
  margin: 0 auto;
}

.links-section__inner {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.link-card {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 24px 28px;
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  backdrop-filter: blur(12px);
  transition: transform 0.3s ease, border-color 0.3s ease, background 0.3s ease;
}

.link-card:hover {
  transform: translateX(4px);
  border-color: rgba(167, 139, 250, 0.25);
  background: var(--color-surface-hover);
}

.link-card__icon {
  font-size: 2rem;
  flex-shrink: 0;
}

.link-card__content {
  flex: 1;
}

.link-card__title {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 2px;
}

.link-card__text {
  font-size: 0.8rem;
  color: var(--color-text-muted);
}

.link-card__arrow {
  font-size: 1.2rem;
  color: var(--color-text-dim);
  transition: color 0.3s, transform 0.3s;
}

.link-card:hover .link-card__arrow {
  color: var(--color-accent);
  transform: translateX(4px);
}

/* ===== Footer ===== */
.footer {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 32px 24px 48px;
  border-top: 1px solid var(--color-border);
}

.footer__text {
  font-size: 0.8rem;
  color: var(--color-text-dim);
  margin-bottom: 12px;
}

.footer__links {
  display: flex;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}

.footer__link {
  font-size: 0.8rem;
  color: var(--color-text-muted);
  transition: color 0.2s;
}

.footer__link:hover {
  color: var(--color-accent);
}

.footer__sep {
  color: var(--color-text-dim);
  font-size: 0.8rem;
}

/* ===== Document Pages (Privacy / Terms) ===== */
.doc-page {
  position: relative;
  z-index: 1;
  max-width: 720px;
  margin: 0 auto;
  padding: 120px 24px 80px;
}

.doc-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  backdrop-filter: blur(16px);
  padding: 48px 40px;
}

.doc-card h1 {
  font-size: 1.6rem;
  font-weight: 700;
  margin-bottom: 8px;
  background: linear-gradient(135deg, var(--color-text) 0%, var(--color-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.doc-card .doc-meta {
  color: var(--color-text-dim);
  font-size: 0.85rem;
  margin-bottom: 40px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--color-border);
}

.doc-card .doc-intro {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  margin-bottom: 32px;
}

.doc-card h2 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-top: 36px;
  margin-bottom: 12px;
  padding-left: 12px;
  border-left: 3px solid var(--color-accent);
}

.doc-card p {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  margin-bottom: 16px;
  line-height: 1.8;
}

.doc-card ul {
  margin-bottom: 16px;
  padding-left: 0;
  list-style: none;
}

.doc-card li {
  position: relative;
  padding-left: 20px;
  color: var(--color-text-muted);
  font-size: 0.9rem;
  margin-bottom: 8px;
  line-height: 1.7;
}

.doc-card li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.65em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-accent-soft);
  border: 1px solid var(--color-accent);
}

.doc-card a {
  color: var(--color-accent);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: opacity 0.2s;
}

.doc-card a:hover {
  opacity: 0.7;
}

.doc-back {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 40px;
  font-size: 0.85rem;
  color: var(--color-text-muted);
  transition: color 0.2s;
}

.doc-back:hover {
  color: var(--color-accent);
}

/* ===== Animations ===== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .hero {
    flex-direction: column;
    text-align: center;
    padding: 100px 20px 60px;
    gap: 40px;
    min-height: auto;
  }

  .hero__content {
    max-width: 100%;
  }

  .hero__description br {
    display: none;
  }

  .hero__badges {
    justify-content: center;
  }

  .hero__cards {
    width: 220px;
    height: 300px;
  }

  .hero__card {
    width: 180px;
    height: 250px;
  }

  .hero__card-emoji {
    font-size: 3rem;
  }

  .features__grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .feature-card {
    text-align: left;
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 20px 24px;
  }

  .feature-card__icon {
    font-size: 2rem;
    margin-bottom: 0;
    flex-shrink: 0;
  }

  .doc-card {
    padding: 32px 24px;
  }

  .header__nav {
    gap: 16px;
  }

  .header__link {
    font-size: 0.8rem;
  }
}

@media (max-width: 480px) {
  .header__inner {
    padding: 14px 16px;
  }

  .header__logo-text {
    font-size: 0.95rem;
  }

  .hero__title {
    font-size: 1.8rem;
  }
}