:root {
  --color-bg: #050811;
  --color-bg-alt: #0e1a2c;
  --color-surface: rgba(17, 34, 56, 0.72);
  --color-primary: #3c8dff;
  --color-primary-dark: #1f6bdb;
  --color-text: #f4f8ff;
  --color-muted: #c4d0ec;
  --color-border: rgba(255, 255, 255, 0.08);
  --font-base: 'Noto Sans JP', 'Hiragino Kaku Gothic ProN', Meiryo, sans-serif;
  --transition: 0.3s ease;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-base);
  background: var(--color-bg);
  color: var(--color-text);
}

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

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

.container {
  width: min(1100px, 90vw);
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(5, 8, 17, 0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.brand img {
  width: 90px;
  filter: drop-shadow(0 0 12px rgba(60, 141, 255, 0.6));
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  font-size: 0.95rem;
}

.site-nav a {
  position: relative;
  padding: 0.4rem 0;
  transition: color var(--transition);
}

.site-nav a::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 2px;
  background: var(--color-primary);
  transform: scaleX(0);
  transform-origin: center;
  transition: transform var(--transition);
}

.site-nav a:hover::after,
.site-nav a:focus-visible::after {
  transform: scaleX(1);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 6px;
  background: none;
  border: none;
  cursor: pointer;
}

.nav-toggle span {
  width: 26px;
  height: 2px;
  background: var(--color-text);
}

.hero {
  position: relative;
  padding: 7rem 0 6rem;
  overflow: hidden;
  --hero-glow-1: rgba(60, 141, 255, 0.3);
  --hero-glow-2: rgba(140, 60, 255, 0.35);
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 20% 20%, var(--hero-glow-1), transparent 55%),
              radial-gradient(circle at 80% 30%, var(--hero-glow-2), transparent 50%);
  transition: background 0.6s ease;
  z-index: -2;
}

.hero[data-theme="xr"] {
  --hero-glow-1: rgba(255, 75, 173, 0.45);
  --hero-glow-2: rgba(90, 200, 255, 0.35);
}

.hero[data-theme="realtime"] {
  --hero-glow-1: rgba(0, 195, 180, 0.4);
  --hero-glow-2: rgba(255, 213, 0, 0.3);
}

.hero .container {
  display: grid;
  align-items: center;
  gap: 3rem;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.hero-copy h1 {
  font-size: clamp(2.2rem, 5vw, 3.2rem);
  margin-bottom: 1rem;
}

.hero-copy p {
  line-height: 1.8;
  color: var(--color-muted);
  max-width: 28rem;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  margin-top: 2rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 140px;
  padding: 0.8rem 1.4rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-weight: 600;
  transition: background var(--transition), color var(--transition), border var(--transition);
}

.btn.primary {
  background: linear-gradient(120deg, var(--color-primary), #7c5cff);
  color: #fff;
}

.btn.primary:hover {
  background: linear-gradient(120deg, var(--color-primary-dark), #6845ff);
}

.btn.ghost {
  border-color: rgba(244, 248, 255, 0.6);
  color: var(--color-muted);
}

.btn.ghost:hover {
  border-color: var(--color-primary);
  color: #fff;
}

.hero-copy {
  transition: opacity 0.3s ease;
}

.hero-copy.is-transitioning {
  opacity: 0;
}

.hero-visual {
  position: relative;
  min-height: 280px;
}

.orb {
  position: absolute;
  border-radius: 50%;
  border: none;
  padding: 0;
  cursor: pointer;
  appearance: none;
  background: transparent;
  filter: drop-shadow(0 0 20px rgba(7, 15, 25, 0.45));
  animation: float 12s ease-in-out infinite;
  transition: transform 0.6s ease, opacity 0.6s ease, box-shadow 0.6s ease, filter 0.6s ease;
}

.orb:focus-visible {
  outline: 2px solid rgba(244, 248, 255, 0.9);
  outline-offset: 4px;
}

.orb.active {
  transform: translateY(-18px) scale(1.08);
  box-shadow: 0 0 32px rgba(60, 141, 255, 0.45);
  animation-play-state: paused;
}

.hero[data-theme="xr"] .orb.active {
  box-shadow: 0 0 32px rgba(255, 75, 173, 0.45);
}

.hero[data-theme="realtime"] .orb.active {
  box-shadow: 0 0 32px rgba(0, 195, 180, 0.45);
}

.orb:nth-child(1) {
  width: 220px;
  height: 220px;
  top: 10%;
  left: 12%;
  background: radial-gradient(circle at 30% 30%, rgba(255, 75, 59, 0.85), rgba(255, 75, 59, 0.3));
}

.orb:nth-child(2) {
  width: 160px;
  height: 160px;
  bottom: 20%;
  right: 15%;
  background: radial-gradient(circle at 30% 30%, rgba(255, 213, 0, 0.85), rgba(255, 213, 0, 0.35));
  animation-delay: -4s;
}

.orb:nth-child(3) {
  width: 120px;
  height: 120px;
  bottom: 0;
  left: 40%;
  background: radial-gradient(circle at 30% 30%, rgba(0, 195, 180, 0.85), rgba(0, 195, 180, 0.3));
  animation-delay: -8s;
}

@keyframes float {
  0%, 100% {
    transform: translateY(0) scale(1);
  }
  50% {
    transform: translateY(-20px) scale(1.05);
  }
}

@media (prefers-reduced-motion: reduce) {
  .orb {
    animation: none;
  }

  .hero-copy {
    transition: none;
  }
}

.section {
  padding: 5rem 0;
  background: rgba(5, 8, 17, 0.95);
}

.section.alt {
  background: var(--color-bg-alt);
}

.section-header {
  text-align: center;
  margin-bottom: 3rem;
}

.section-header h2 {
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  margin-bottom: 1rem;
}

.section-header p {
  color: var(--color-muted);
  max-width: 520px;
  margin: 0 auto;
  line-height: 1.7;
}

.columns {
  display: grid;
  gap: 1.5rem;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.columns.two {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.column-card {
  padding: 2rem;
  border-radius: 18px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  box-shadow: 0 18px 40px rgba(7, 15, 25, 0.35);
}

.column-card h3 {
  margin-top: 0;
  margin-bottom: 1rem;
}

.column-card p,
.column-card ul {
  color: var(--color-muted);
  line-height: 1.8;
}

.column-card ul {
  padding-left: 1.2rem;
}

.column-card li {
  margin-bottom: 0.5rem;
}

.feature-card {
  display: grid;
  gap: 2rem;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  align-items: center;
  padding: 2.5rem;
  background: var(--color-surface);
  border-radius: 24px;
  border: 1px solid var(--color-border);
  box-shadow: 0 20px 50px rgba(7, 15, 25, 0.4);
}

.feature-card + .feature-card {
  margin-top: 2.5rem;
}

.feature-text h3 {
  font-size: 1.8rem;
  margin-bottom: 0.75rem;
}

.feature-text p {
  color: var(--color-muted);
  line-height: 1.8;
  margin-bottom: 1.5rem;
}

.feature-actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.feature-media img {
  max-width: 220px;
  margin-left: auto;
}

.contact-card {
  display: grid;
  gap: 1.5rem;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  padding: 2.5rem;
  background: var(--color-surface);
  border-radius: 20px;
  border: 1px solid var(--color-border);
  text-align: center;
}

.contact-card h3 {
  margin-bottom: 0.75rem;
}

.site-footer {
  padding: 2rem 0;
  background: #03070f;
  border-top: 1px solid var(--color-border);
}

.site-footer .container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--color-muted);
}

.site-footer a {
  color: #9bb9ff;
}

@media (max-width: 800px) {
  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    top: 64px;
    right: 5vw;
    flex-direction: column;
    gap: 1rem;
    padding: 1.5rem;
    background: rgba(5, 8, 17, 0.96);
    border: 1px solid var(--color-border);
    border-radius: 16px;
    transform: translateY(-20px);
    opacity: 0;
    pointer-events: none;
    transition: var(--transition);
  }

  .site-nav.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  .hero {
    padding-top: 6rem;
  }
}

@media (max-width: 540px) {
  .hero-actions {
    flex-direction: column;
  }
}
