/* 全ページ共通 */
html {
  font-size: 16px;
  overflow-x: hidden;
}
body {
  overflow-x: hidden;
}
img, svg {
  display: block;
  max-width: 100%;
}

/* ========================================
   共通ナビゲーション
   ======================================== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  padding: 16px 64px;
  box-sizing: border-box;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: rgba(10, 10, 10, 0.8);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}

.nav__logo { flex-shrink: 0; }

.nav__logo img {
  height: 44px;
  width: auto;
  max-width: none;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav__links a {
  font-family: 'Poppins', sans-serif;
  font-size: 1.125rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #e8e8e8;
  transition: color 0.3s ease;
  position: relative;
  text-decoration: none;
}

.nav__links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 1px;
  background: currentColor;
  transition: width 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.nav__links a:hover { color: #ffffff; text-decoration: none; }
.nav__links a:hover::after { width: 100%; }

.nav__toggle {
  display: none;
  flex-direction: column;
  gap: 7px;
  padding: 8px;
  background: none;
  border: none;
  z-index: 1001;
  cursor: pointer;
}

.nav__toggle span {
  width: 28px;
  height: 1px;
  background: #ffffff;
  transition: all 0.3s ease;
  display: block;
}

/* ========================================
   MOBILE NAV OVERLAY
   ======================================== */
.nav.nav--open {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100vh;
  height: 100dvh;
  background: rgba(10, 10, 10, 0.98);
  backdrop-filter: blur(20px);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  z-index: 100;
  overflow: hidden;
}
.nav.nav--open::before,
.nav.nav--open::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  background-image:
    radial-gradient(1px 1px at 10% 20%, rgba(255,255,255,0.6) 50%, transparent 100%),
    radial-gradient(1px 1px at 25% 55%, rgba(255,255,255,0.4) 50%, transparent 100%),
    radial-gradient(1px 1px at 40% 15%, rgba(255,255,255,0.5) 50%, transparent 100%),
    radial-gradient(1px 1px at 55% 70%, rgba(255,255,255,0.3) 50%, transparent 100%),
    radial-gradient(1px 1px at 70% 35%, rgba(255,255,255,0.6) 50%, transparent 100%),
    radial-gradient(1px 1px at 85% 80%, rgba(255,255,255,0.4) 50%, transparent 100%),
    radial-gradient(1px 1px at 15% 85%, rgba(255,255,255,0.3) 50%, transparent 100%),
    radial-gradient(1px 1px at 60% 45%, rgba(255,255,255,0.5) 50%, transparent 100%),
    radial-gradient(1px 1px at 90% 10%, rgba(255,255,255,0.4) 50%, transparent 100%),
    radial-gradient(1.5px 1.5px at 30% 40%, rgba(255,255,255,0.7) 50%, transparent 100%),
    radial-gradient(1px 1px at 75% 60%, rgba(255,255,255,0.3) 50%, transparent 100%),
    radial-gradient(1px 1px at 5% 50%, rgba(255,255,255,0.5) 50%, transparent 100%),
    radial-gradient(1.5px 1.5px at 50% 90%, rgba(255,255,255,0.6) 50%, transparent 100%),
    radial-gradient(1px 1px at 95% 45%, rgba(255,255,255,0.4) 50%, transparent 100%),
    radial-gradient(1px 1px at 45% 5%, rgba(255,255,255,0.5) 50%, transparent 100%);
  background-size: 100% 100%;
  animation: starTwinkle 1.5s ease-in-out infinite alternate;
}
.nav.nav--open::after {
  background-image:
    radial-gradient(1px 1px at 18% 30%, rgba(255,255,255,0.5) 50%, transparent 100%),
    radial-gradient(1px 1px at 33% 75%, rgba(255,255,255,0.3) 50%, transparent 100%),
    radial-gradient(1.5px 1.5px at 48% 25%, rgba(255,255,255,0.6) 50%, transparent 100%),
    radial-gradient(1px 1px at 63% 55%, rgba(255,255,255,0.4) 50%, transparent 100%),
    radial-gradient(1px 1px at 78% 15%, rgba(255,255,255,0.5) 50%, transparent 100%),
    radial-gradient(1px 1px at 8% 65%, rgba(255,255,255,0.3) 50%, transparent 100%),
    radial-gradient(1px 1px at 88% 50%, rgba(255,255,255,0.4) 50%, transparent 100%),
    radial-gradient(1.5px 1.5px at 22% 95%, rgba(255,255,255,0.5) 50%, transparent 100%),
    radial-gradient(1px 1px at 52% 8%, rgba(255,255,255,0.6) 50%, transparent 100%),
    radial-gradient(1px 1px at 72% 85%, rgba(255,255,255,0.3) 50%, transparent 100%);
  background-size: 100% 100%;
  animation: starTwinkle 2s ease-in-out infinite alternate-reverse;
}
@keyframes starTwinkle {
  0% { opacity: 0.4; }
  50% { opacity: 0.85; }
  100% { opacity: 0.45; }
}
.nav.nav--open .nav__links {
  display: flex !important;
  flex-direction: column;
  align-items: center;
  gap: 32px;
  list-style: none;
  padding: 0;
  margin: 0;
}
.nav.nav--open .nav__links li { list-style: none; }
.nav.nav--open .nav__links a {
  font-size: 20px;
  color: #ffffff;
  letter-spacing: 0.15em;
}
.nav.nav--open .nav__toggle {
  position: absolute;
  left: 16px;
  top: calc(max(20px, env(safe-area-inset-top)) + 16px);
  transform: translateY(-50%);
}
.nav.nav--open .nav__logo {
  position: absolute;
  top: max(20px, env(safe-area-inset-top));
  left: 50%;
  transform: translateX(-50%);
}

/* ========================================
   CUSTOM CURSOR — 全ページ共通
   ======================================== */
.cursor-trail {
  position: fixed;
  top: 0;
  left: 0;
  width: 20px;
  height: 20px;
  background: rgba(0, 197, 252, 0.5);
  border-radius: 50%;
  pointer-events: none;
  z-index: 10000;
  will-change: transform, opacity;
  opacity: 0;
}

@keyframes cursorPulse {
  0% { transform: translate(var(--cx), var(--cy)) scale(1); opacity: var(--base-opacity); }
  50% { transform: translate(var(--cx), var(--cy)) scale(1.3); opacity: calc(var(--base-opacity) * 0.4); }
  100% { transform: translate(var(--cx), var(--cy)) scale(1); opacity: var(--base-opacity); }
}

/* ========================================
   MOBILE — 768px以下
   ======================================== */
@media (max-width: 768px) {
  .cursor-trail { display: none !important; }
  .nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 100;
    padding: 20px 16px;
    box-sizing: border-box;
    padding-top: max(20px, env(safe-area-inset-top));
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    background: rgba(10, 10, 10, 0.95);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
  }
  .nav__toggle {
    display: flex;
    grid-column: 1;
    grid-row: 1;
    justify-self: start;
    flex-direction: column;
    gap: 7px;
    padding: 8px;
  }
  .nav__logo {
    grid-column: 2;
    grid-row: 1;
    justify-self: center;
  }
  .nav__logo img { height: 32px; }
  .nav__links { display: none; }
}