/* ───────────────────────── Starlabs Go · 公共样式 ───────────────────────── */

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --black: #0A0A0A;
  --white: #FFFFFF;
  --off-white: #F5F5F3;
  --gray-100: #F0EFED;
  --gray-200: #E0DFDC;
  --gray-300: #C8C7C3;
  --gray-400: #A8A7A3;
  --gray-500: #787672;
  --gray-600: #4A4845;
  --gray-700: #2E2D2B;
  --border: #E0DFDC;
  --border-dark: rgba(255,255,255,0.1);
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Archivo', 'Noto Sans SC', -apple-system, sans-serif;
  background: var(--white);
  color: var(--black);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* ── NAV ── */
nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 3rem; height: 64px;
  background: var(--white);
  border-bottom: 1px solid var(--border);
  transition: background 0.3s;
}
nav.dark-mode { background: var(--black); border-color: var(--border-dark); }
.nav-logo img { display: block; height: 28px; width: auto; transition: opacity 0.2s; }
.nav-logo:hover img { opacity: 0.6; }
.nav-links { display: flex; align-items: center; gap: 2.5rem; list-style: none; }
.nav-links a { text-decoration: none; color: var(--gray-700); font-size: 18px; font-weight: 400; letter-spacing: 0.02em; transition: color 0.2s; }
nav.dark-mode .nav-links a { color: rgba(255,255,255,0.72); }
.nav-links a:hover { color: var(--black); }
nav.dark-mode .nav-links a:hover { color: var(--white); }
.nav-cta { background: var(--black) !important; color: var(--white) !important; padding: 0.5rem 1.25rem; border-radius: 2px; font-size: 12px !important; font-weight: 500 !important; letter-spacing: 0.04em !important; transition: opacity 0.2s !important; }
nav.dark-mode .nav-cta { background: var(--white) !important; color: var(--black) !important; }
.nav-cta:hover { opacity: 0.7 !important; }

.lang-switch { display: flex; align-items: center; border: 1px solid rgba(0,0,0,0.15); border-radius: 2px; overflow: hidden; }
nav.dark-mode .lang-switch { border-color: rgba(255,255,255,0.2); }
.lang-btn { font-family: 'Archivo', 'Noto Sans SC', sans-serif; font-size: 11px; font-weight: 600; letter-spacing: 0.06em; padding: 0.3rem 0.65rem; border: none; background: transparent; cursor: pointer; color: rgba(0,0,0,0.3); transition: background 0.2s, color 0.2s; text-decoration: none; display: inline-block; }
.lang-btn.active { background: rgba(0,0,0,0.08); color: var(--black); }
nav.dark-mode .lang-btn { color: rgba(255,255,255,0.45); }
nav.dark-mode .lang-btn.active { background: rgba(255,255,255,0.15); color: var(--white); }
.lang-divider { width: 1px; height: 16px; background: currentColor; opacity: 0.2; }

/* ── FOOTER ── */
footer {
  background: var(--black);
  border-top: 1px solid rgba(255,255,255,0.08);
  padding: 2.5rem 3rem;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 2rem;
}
.footer-logo img { display: block; height: 18px; width: auto; opacity: 0.6; }
.footer-logo:hover img { opacity: 1; }
.footer-links { display: flex; align-items: center; justify-content: center; gap: 2.5rem; list-style: none; flex-wrap: wrap; }
.footer-links a { text-decoration: none; font-size: 14px; color: var(--gray-600); letter-spacing: 0.03em; transition: color 0.2s; }
.footer-links a:hover { color: rgba(255,255,255,0.7); }
.footer-copy { font-size: 14px; color: rgba(255,255,255,0.4); letter-spacing: 0.03em; white-space: nowrap; }

/* ── SCROLL REVEAL ── */
.reveal { opacity: 0; transform: translateY(30px); transition: opacity 0.8s ease, transform 0.8s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }

/* ── 兜底模板（index.php）── */
.fallback-main { max-width: 800px; margin: 0 auto; padding: 8rem 3rem 5rem; }
.fallback-title { font-size: clamp(1.75rem, 4vw, 2.5rem); font-weight: 800; letter-spacing: -0.03em; margin-bottom: 2.5rem; }
.fallback-content p { margin-bottom: 1.25rem; color: var(--gray-600); }
.fallback-empty { color: var(--gray-500); }

/* ── RESPONSIVE ── */
@media (max-width: 900px) {
  nav { padding: 0 1.5rem; }
  .nav-links { display: none; }
  footer { padding: 2rem 1.5rem; grid-template-columns: 1fr; justify-items: start; }
  .footer-links { justify-content: flex-start; }
  .fallback-main { padding: 7rem 1.5rem 3rem; }
}