/* ═══════════════════════════════════════════════
   ZENNA NEX — Cosmic Design System
   Dark solar system aesthetic. Translucent glass UI.
   Matches companion/index.html design tokens.
   ═══════════════════════════════════════════════ */

@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@300;400;500;600;700&display=swap');

:root {
  --bg-dark: #040819;
  --bg-deeper: #020510;
  --glass: rgba(5, 10, 34, 0.45);
  --glass-border: rgba(112, 198, 255, 0.18);
  --glass-border-bright: rgba(112, 198, 255, 0.5);
  --cyan: #4be2ff;
  --violet: #9c6bff;
  --gold: #ffd475;
  --text-primary: #f5fbff;
  --text-secondary: rgba(245, 251, 255, 0.72);
  --text-muted: rgba(245, 251, 255, 0.4);
  --glow-cyan: rgba(75, 226, 255, 0.35);
  --glow-violet: rgba(156, 107, 255, 0.25);
}

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

html, body {
  height: 100%;
  overflow: hidden;
}

body {
  font-family: "Space Grotesk", system-ui, sans-serif;
  background: var(--bg-dark);
  color: var(--text-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ─── Starfield canvas (behind everything) ─── */
#starfield {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
}

/* ─── Nebula gradient overlay ─── */
.nebula {
  position: fixed;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background:
    radial-gradient(ellipse 80% 60% at 20% 80%, rgba(156, 107, 255, 0.08), transparent),
    radial-gradient(ellipse 60% 50% at 80% 20%, rgba(75, 226, 255, 0.06), transparent),
    radial-gradient(ellipse 90% 70% at 50% 50%, rgba(75, 226, 255, 0.03), transparent);
  animation: nebulaShift 30s ease-in-out infinite alternate;
}

@keyframes nebulaShift {
  0% { opacity: 0.7; transform: scale(1) translate(0, 0); }
  50% { opacity: 1; transform: scale(1.05) translate(-1%, 1%); }
  100% { opacity: 0.8; transform: scale(1.02) translate(1%, -0.5%); }
}

/* ─── Content layer ─── */
.page-content {
  position: relative;
  z-index: 2;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

/* ─── Glass panel ─── */
.glass-panel {
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  background: var(--glass);
  border: 1px solid var(--glass-border);
  border-radius: 24px;
  padding: 32px;
}

/* ─── Glass button ─── */
.glass-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 16px 40px;
  border: 1px solid rgba(75, 226, 255, 0.3);
  border-radius: 999px;
  background: rgba(75, 226, 255, 0.08);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  color: var(--text-primary);
  font-family: inherit;
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
  transition: all 300ms ease;
  text-decoration: none;
}

.glass-btn:hover {
  background: rgba(75, 226, 255, 0.15);
  border-color: rgba(75, 226, 255, 0.5);
  box-shadow: 0 0 30px var(--glow-cyan), 0 0 60px rgba(75, 226, 255, 0.1);
  transform: translateY(-2px);
}

.glass-btn:active {
  transform: translateY(0);
}

.glass-btn.primary {
  background: linear-gradient(135deg, rgba(75, 226, 255, 0.2), rgba(156, 107, 255, 0.15));
  border-color: rgba(75, 226, 255, 0.4);
  box-shadow: 0 0 20px var(--glow-cyan);
}

.glass-btn.primary:hover {
  background: linear-gradient(135deg, rgba(75, 226, 255, 0.3), rgba(156, 107, 255, 0.2));
  box-shadow: 0 0 40px var(--glow-cyan), 0 0 80px rgba(75, 226, 255, 0.15);
}

/* ─── Logo ─── */
.zenna-logo {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 700;
  letter-spacing: 0.25em;
  text-transform: uppercase;
  background: linear-gradient(135deg, var(--cyan), var(--violet), var(--cyan));
  background-size: 200% 200%;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: logoShimmer 8s ease-in-out infinite;
  filter: drop-shadow(0 0 30px rgba(75, 226, 255, 0.3));
  user-select: none;
}

@keyframes logoShimmer {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

/* ─── Tagline ─── */
.tagline {
  font-size: clamp(0.9rem, 2vw, 1.15rem);
  color: var(--text-secondary);
  letter-spacing: 0.12em;
  text-align: center;
  margin-top: 16px;
}

/* ─── Subtle link ─── */
.subtle-link {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.85rem;
  letter-spacing: 0.04em;
  transition: color 200ms;
}

.subtle-link:hover {
  color: var(--cyan);
}

/* ─── Fade-in animation ─── */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  animation: fadeInUp 800ms ease forwards;
}

.fade-in.d1 { animation-delay: 200ms; }
.fade-in.d2 { animation-delay: 400ms; }
.fade-in.d3 { animation-delay: 600ms; }
.fade-in.d4 { animation-delay: 800ms; }

@keyframes fadeInUp {
  to { opacity: 1; transform: translateY(0); }
}

/* ─── Mobile ─── */
@media (max-width: 640px) {
  .page-content { padding: 16px; }
  .glass-btn { padding: 14px 28px; font-size: 0.95rem; }
  .glass-panel { padding: 24px 20px; border-radius: 20px; }
}