/* 共通: ヘッダー・フッター・ページレイアウト */
:root {
  --color-base: #1A1A1A;
  --color-text: #F5F5F5;
  --color-text-muted: #AAAAAA;
  --color-accent: #FFD700;
  --color-footer: #111111;
  --font-heading: 'Montserrat', 'Playfair Display', sans-serif;
  --font-body: 'Noto Sans JP', 'Hiragino Kaku Gothic ProN', 'メイリオ', sans-serif;
  --transition-base: 0.3s ease;
}

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-body);
  background-color: var(--color-base);
  color: var(--color-text);
  line-height: 1.8;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
a { text-decoration: none; color: inherit; }

.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(26, 26, 26, 0.6);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  transition: background var(--transition-base);
}
.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.logo {
  font-family: var(--font-heading);
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: 1px;
  color: var(--color-text);
  white-space: nowrap;
}
.nav { display: flex; align-items: center; gap: 32px; }
.nav a {
  font-family: var(--font-heading);
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--color-text);
  position: relative;
  transition: color var(--transition-base);
}
.nav a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-accent);
  transition: width var(--transition-base);
}
.nav a:hover { color: var(--color-accent); }
.nav a:hover::after { width: 100%; }

.nav a.active { color: var(--color-accent); }
.nav a.active::after { width: 100%; }

.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  background: none;
  border: none;
  padding: 4px;
}
.menu-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: all var(--transition-base);
}
.menu-toggle.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
.menu-toggle.active span:nth-child(2) { opacity: 0; }
.menu-toggle.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

.page-content {
  padding: 100px 24px 80px;
  max-width: 800px;
  margin: 0 auto;
  min-height: 60vh;
}
.page-content h1 {
  font-family: var(--font-heading);
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 700;
  letter-spacing: 2px;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 2px solid var(--color-accent);
}
.page-content p {
  color: var(--color-text-muted);
  margin-bottom: 1rem;
  line-height: 1.9;
}

.footer {
  background: var(--color-footer);
  padding: 48px 24px;
  text-align: center;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
}
.footer-socials {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin-bottom: 28px;
}
.footer-socials a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: var(--color-text-muted);
  transition: all var(--transition-base);
}
.footer-socials a:hover {
  color: var(--color-accent);
  border-color: var(--color-accent);
  transform: translateY(-3px);
  box-shadow: 0 4px 16px rgba(255, 215, 0, 0.2);
}
.footer-socials svg { width: 18px; height: 18px; fill: currentColor; }
.footer-copy { font-size: 0.8rem; color: var(--color-text-muted); letter-spacing: 0.5px; }
.footer-links { margin-top: 12px; font-size: 0.8rem; color: var(--color-text-muted); }
.footer-links a { color: var(--color-text-muted); transition: color var(--transition-base); }
.footer-links a:hover { color: var(--color-accent); }

@media (max-width: 768px) {
  .menu-toggle { display: flex; }
  .nav {
    position: fixed;
    top: 72px;
    right: 0;
    width: 100%;
    height: calc(100vh - 72px);
    flex-direction: column;
    justify-content: flex-start;
    padding-top: 40px;
    gap: 0;
    background: rgba(26, 26, 26, 0.95);
    backdrop-filter: blur(20px);
    transform: translateX(100%);
    transition: transform 0.4s ease;
  }
  .nav.open { transform: translateX(0); }
  .nav a { font-size: 1.1rem; padding: 16px 0; width: 100%; text-align: center; border-bottom: 1px solid rgba(255,255,255,0.05); }
  .page-content { padding: 88px 16px 60px; }
  .header-inner { padding: 0 16px; }
}
@media (max-width: 480px) {
  .logo { font-size: 1.1rem; }
}