/* ============ CSS Variables ============ */
:root {
  --color-primary: #2B4C9B;
  --color-primary-dark: #1E3A7A;
  --color-primary-light: #3D62BD;
  --color-primary-rgb: 43, 76, 155;
  --color-secondary: #0EA5E9;
  --color-accent: #06B6D4;
  --color-bg: #FAFBFD;
  --color-bg-rgb: 250, 251, 253;
  --color-bg-dark: #0F1729;
  --color-text: #1A1D2B;
  --color-text-muted: #64748B;
  --color-border: #E2E8F0;
  --ease-out-expo: cubic-bezier(0.22, 1, 0.36, 1);
}

/* ============ Base ============ */
html {
  scroll-padding-top: 80px;
}

/* ============ Gradient Text ============ */
.gradient-text {
  background: linear-gradient(135deg, #60A5FA 0%, #06B6D4 50%, #34D399 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ============ Header States ============ */
.header-transparent {
  background: transparent;
}
.header-transparent a,
.header-transparent button,
.header-transparent span {
  color: white;
  text-shadow: 0 1px 3px rgba(0,0,0,0.3);
}
.header-transparent .nav-cta {
  background: rgba(255,255,255,0.15);
  border: 1px solid rgba(255,255,255,0.2);
}
.header-transparent .nav-cta:hover {
  background: rgba(255,255,255,0.25);
}

.header-scrolled {
  background: rgba(var(--color-bg-rgb), 0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 1px 3px rgba(0,0,0,0.06), 0 4px 12px rgba(0,0,0,0.04);
}
.header-scrolled a,
.header-scrolled button,
.header-scrolled span {
  color: var(--color-text);
  text-shadow: none;
}
.header-scrolled .nav-cta {
  background: var(--color-primary);
  color: white !important;
  border: none;
  text-shadow: none !important;
}
.header-scrolled .nav-cta:hover {
  background: var(--color-primary-dark);
}

/* ============ Hero Buttons ============ */
.btn-hero-primary {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
  color: white;
  box-shadow: 0 4px 15px rgba(var(--color-primary-rgb), 0.4);
}
.btn-hero-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(var(--color-primary-rgb), 0.5);
}

/* ============ Service Cards ============ */
.service-card {
  transition: transform 0.3s var(--ease-out-expo), border-color 0.3s ease;
  position: relative;
}
.service-card::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: inherit;
  box-shadow: 0 10px 40px rgba(0,0,0,0.08);
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
}
.service-card:hover {
  transform: translateY(-4px);
  border-color: rgba(var(--color-primary-rgb), 0.2);
}
.service-card:hover::after {
  opacity: 1;
}

/* ============ Review Cards ============ */
.review-card {
  transition: transform 0.3s var(--ease-out-expo);
  position: relative;
}
.review-card::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: inherit;
  box-shadow: 0 8px 30px rgba(0,0,0,0.06);
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
}
.review-card:hover {
  transform: translateY(-2px);
}
.review-card:hover::after {
  opacity: 1;
}

/* ============ Glow Button ============ */
.btn-glow {
  position: relative;
  z-index: 1;
}
.btn-glow::before {
  content: '';
  position: absolute;
  inset: -2px;
  border-radius: inherit;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  z-index: -1;
  opacity: 0;
  filter: blur(12px);
  transition: opacity 0.4s ease;
}
.btn-glow:hover::before {
  opacity: 0.5;
}

/* ============ CSS Grid Background ============ */
.css-grid-bg {
  background-image:
    linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 60px 60px;
}

/* ============ Scroll Animations ============ */
.animate-on-scroll {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s var(--ease-out-expo), transform 0.7s var(--ease-out-expo);
}
.animate-visible {
  opacity: 1;
  transform: translateY(0);
}

/* Stagger for grid children */
.animate-on-scroll:nth-child(2) { transition-delay: 0.1s; }
.animate-on-scroll:nth-child(3) { transition-delay: 0.2s; }
.animate-on-scroll:nth-child(4) { transition-delay: 0.3s; }

/* ============ Responsive ============ */
@media (max-width: 768px) {
  .header-transparent .nav-cta,
  .header-scrolled .nav-cta {
    display: none;
  }
}