/* ============================================================
   SureMILE — Ultra-Modern Dark Design System (base.css)
   Premium glassmorphism, neon glows, gradient accents
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:ital,wght@0,300;0,400;0,500;0,600;0,700;0,800;1,300;1,400;1,500;1,600;1,700;1,800&display=swap');

/* ── CSS Variables ─────────────────────────────────────────── */
:root {
  /* Brand */
  --primary: #3B82F6;
  --primary-hover: #60A5FA;
  --primary-glow: rgba(59, 130, 246, 0.4);
  --secondary: #06B6D4;
  --accent: #F59E0B;
  --accent-hover: #FBBF24;
  --accent-glow: rgba(245, 158, 11, 0.35);
  --success: #10B981;
  --warning: #F97316;
  --error: #EF4444;

  /* Backgrounds — deep dark with subtle blue undertone */
  --bg-base: #030712;
  --bg-surface: #0F172A;
  --bg-card: #1E293B;
  --bg-elevated: #334155;
  --bg-glass: rgba(15, 23, 42, 0.6);
  --bg-glass-hover: rgba(30, 41, 59, 0.8);

  /* Text */
  --text-primary: #F8FAFC;
  --text-secondary: #CBD5E1;
  --text-muted: #64748B;

  /* Borders & Effects */
  --border-subtle: rgba(148, 163, 184, 0.1);
  --border-glass: rgba(148, 163, 184, 0.15);
  --border-glow: rgba(59, 130, 246, 0.3);
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.6);
  --shadow-xl: 0 20px 50px rgba(0, 0, 0, 0.7);
  --shadow-glow-blue: 0 0 30px rgba(59, 130, 246, 0.15), 0 0 60px rgba(59, 130, 246, 0.05);
  --shadow-glow-amber: 0 0 30px rgba(245, 158, 11, 0.15), 0 0 60px rgba(245, 158, 11, 0.05);

  /* Spacing */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;
  --space-4xl: 96px;

  /* Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  /* Layout */
  --max-width: 1200px;
  --nav-height: 72px;

  /* Transitions */
  --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-spring: 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-secondary);
  background: var(--bg-base);
  color-scheme: dark;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Subtle animated grain texture background */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background:
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(59, 130, 246, 0.08) 0%, transparent 60%),
    radial-gradient(ellipse 60% 40% at 80% 60%, rgba(6, 182, 212, 0.04) 0%, transparent 50%),
    radial-gradient(ellipse 50% 30% at 10% 80%, rgba(245, 158, 11, 0.03) 0%, transparent 50%);
  pointer-events: none;
  z-index: 0;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; height: auto; display: block; }

/* ── Typography ────────────────────────────────────────────── */
h1, h2, h3, h4, h5, h6 {
  color: var(--text-primary);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2.5rem, 5.5vw, 4rem); font-weight: 800; }
h2 { font-size: clamp(1.75rem, 3.5vw, 2.5rem); }
h3 { font-size: 1.25rem; }

p { margin-bottom: var(--space-md); }
p:last-child { margin-bottom: 0; }

/* Vivid gradient text */
.text-gradient {
  background: linear-gradient(135deg, #60A5FA 0%, #38BDF8 40%, #06B6D4 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Amber tagline with glow */
.tagline {
  display: inline-block;
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
  margin-bottom: var(--space-md);
  text-shadow: 0 0 20px var(--accent-glow);
}

.text-muted { color: var(--text-muted); }
.text-center { text-align: center; }

/* ── Layout ────────────────────────────────────────────────── */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-xl);
  position: relative;
  z-index: 1;
}

.section {
  padding: var(--space-4xl) 0;
  position: relative;
}

.section--surface {
  background: var(--bg-surface);
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}

.section--gradient {
  background: linear-gradient(180deg, rgba(59, 130, 246, 0.06) 0%, var(--bg-base) 100%);
}

.section--blue {
  background: linear-gradient(135deg, #1E3A8A 0%, #1E40AF 30%, #2563EB 100%);
  color: white;
  position: relative;
  overflow: hidden;
}

/* Subtle animated orb behind blue sections */
.section--blue::before {
  content: '';
  position: absolute;
  width: 500px;
  height: 500px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(96, 165, 250, 0.2) 0%, transparent 70%);
  top: -200px;
  right: -100px;
  animation: float 8s ease-in-out infinite;
}

/* ── Grid Layouts ──────────────────────────────────────────── */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-xl);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xl);
}

@media (max-width: 768px) {
  .grid-2, .grid-3 { grid-template-columns: 1fr; }
}

/* ── Scroll Reveal ─────────────────────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s cubic-bezier(0.4, 0, 0.2, 1), transform 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Staggered children animation */
.reveal-children > * {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s cubic-bezier(0.4, 0, 0.2, 1), transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.reveal-children.visible > *:nth-child(1) { transition-delay: 0.05s; opacity: 1; transform: translateY(0); }
.reveal-children.visible > *:nth-child(2) { transition-delay: 0.15s; opacity: 1; transform: translateY(0); }
.reveal-children.visible > *:nth-child(3) { transition-delay: 0.25s; opacity: 1; transform: translateY(0); }
.reveal-children.visible > *:nth-child(4) { transition-delay: 0.35s; opacity: 1; transform: translateY(0); }
.reveal-children.visible > *:nth-child(5) { transition-delay: 0.45s; opacity: 1; transform: translateY(0); }
.reveal-children.visible > *:nth-child(6) { transition-delay: 0.55s; opacity: 1; transform: translateY(0); }

/* ── Animations ────────────────────────────────────────────── */
@keyframes float {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(3deg); }
}

@keyframes pulse-glow {
  0%, 100% { box-shadow: 0 0 20px rgba(59, 130, 246, 0.2); }
  50% { box-shadow: 0 0 40px rgba(59, 130, 246, 0.4); }
}

@keyframes shimmer {
  0% { background-position: -200% center; }
  100% { background-position: 200% center; }
}

@keyframes gradient-shift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

/* ── Responsive ────────────────────────────────────────────── */
@media (max-width: 768px) {
  .container { padding: 0 var(--space-md); }
  .section { padding: var(--space-3xl) 0; }
}