/* ============================================================
   Birdview Energy — modern interaction layer
   Standalone CSS (no build step required). Classes prefixed bv-.
   ============================================================ */

/* ---------- Scroll progress bar ---------- */
.bv-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0;
  background: linear-gradient(90deg, #2174ea, #34d399, #5696ff);
  z-index: 60;
  transition: width 80ms linear;
  pointer-events: none;
}

/* ---------- Sticky glass header ---------- */
#site-header {
  transition: background-color 300ms ease, box-shadow 300ms ease, backdrop-filter 300ms ease, transform 300ms ease;
}
#site-header.bv-stuck {
  position: fixed;
  top: 0;
  background: rgba(16, 29, 45, 0.82);
  -webkit-backdrop-filter: blur(12px) saturate(160%);
  backdrop-filter: blur(12px) saturate(160%);
  box-shadow: 0 8px 32px rgba(2, 8, 20, 0.35);
  animation: bv-header-in 350ms ease both;
}
@keyframes bv-header-in {
  from { transform: translateY(-100%); }
  to   { transform: translateY(0); }
}

/* ---------- Hero: aurora + grid + particles ---------- */
.bv-hero-bg {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
}
.bv-hero-bg::before {
  /* faint engineering grid */
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(86, 150, 255, 0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(86, 150, 255, 0.07) 1px, transparent 1px);
  background-size: 48px 48px;
  -webkit-mask-image: radial-gradient(ellipse 90% 80% at 50% 30%, black 40%, transparent 100%);
  mask-image: radial-gradient(ellipse 90% 80% at 50% 30%, black 40%, transparent 100%);
}
.bv-aurora {
  position: absolute;
  border-radius: 9999px;
  filter: blur(90px);
  opacity: 0.5;
  will-change: transform;
}
.bv-aurora-1 {
  width: 640px; height: 640px;
  left: -160px; top: -220px;
  background: radial-gradient(circle at center, rgba(33, 116, 234, 0.55), transparent 65%);
  animation: bv-drift-1 18s ease-in-out infinite alternate;
}
.bv-aurora-2 {
  width: 560px; height: 560px;
  right: -140px; top: -80px;
  background: radial-gradient(circle at center, rgba(52, 211, 153, 0.35), transparent 65%);
  animation: bv-drift-2 22s ease-in-out infinite alternate;
}
.bv-aurora-3 {
  width: 480px; height: 480px;
  left: 35%; bottom: -180px;
  background: radial-gradient(circle at center, rgba(86, 150, 255, 0.3), transparent 65%);
  animation: bv-drift-3 26s ease-in-out infinite alternate;
}
@keyframes bv-drift-1 { from { transform: translate(0, 0) scale(1); } to { transform: translate(90px, 60px) scale(1.15); } }
@keyframes bv-drift-2 { from { transform: translate(0, 0) scale(1.1); } to { transform: translate(-70px, 50px) scale(0.95); } }
@keyframes bv-drift-3 { from { transform: translate(0, 0); } to { transform: translate(60px, -50px); } }

#bv-particles {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

/* ---------- Badge pulse ---------- */
.bv-pulse-dot {
  position: relative;
  display: inline-block;
  width: 8px; height: 8px;
  margin-right: 8px;
  border-radius: 9999px;
  background: #10b981;
  vertical-align: middle;
}
.bv-pulse-dot::after {
  content: "";
  position: absolute;
  inset: -4px;
  border-radius: 9999px;
  background: rgba(16, 185, 129, 0.4);
  animation: bv-ping 2s cubic-bezier(0, 0, 0.2, 1) infinite;
}
@keyframes bv-ping {
  0%   { transform: scale(0.6); opacity: 1; }
  75%, 100% { transform: scale(1.8); opacity: 0; }
}

/* ---------- Gradient text ---------- */
.bv-gradient-text {
  background: linear-gradient(100deg, #5696ff 0%, #34d399 60%, #a7f3d0 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  background-size: 200% 200%;
  animation: bv-gradient-shift 6s ease infinite;
}
@keyframes bv-gradient-shift {
  0%, 100% { background-position: 0% 50%; }
  50%      { background-position: 100% 50%; }
}

/* ---------- Buttons ---------- */
.bv-btn-glow {
  position: relative;
  overflow: hidden;
  transition: transform 200ms ease, box-shadow 200ms ease;
}
.bv-btn-glow:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 30px -8px rgba(33, 116, 234, 0.65);
}
.bv-btn-glow::after {
  /* shine sweep */
  content: "";
  position: absolute;
  top: 0; left: -80%;
  width: 50%; height: 100%;
  background: linear-gradient(105deg, transparent, rgba(255, 255, 255, 0.35), transparent);
  transform: skewX(-20deg);
  transition: left 600ms ease;
  pointer-events: none;
}
.bv-btn-glow:hover::after { left: 130%; }

.bv-btn-outline {
  transition: transform 200ms ease, box-shadow 200ms ease, border-color 200ms ease;
}
.bv-btn-outline:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 25px -10px rgba(15, 23, 42, 0.4);
}

/* ---------- Hero visual: float + tilt + glow ---------- */
.bv-float { animation: bv-float 7s ease-in-out infinite; }
@keyframes bv-float {
  0%, 100% { transform: translateY(0); }
  50%      { transform: translateY(-12px); }
}
.bv-tilt {
  transform-style: preserve-3d;
  transition: transform 300ms ease;
  will-change: transform;
}
.bv-hero-shot {
  border-radius: 10px;
  box-shadow:
    0 0 0 1px rgba(86, 150, 255, 0.25),
    0 20px 60px -15px rgba(2, 8, 20, 0.8),
    0 0 80px -20px rgba(33, 116, 234, 0.45);
}

/* ---------- Stats bar + counters ---------- */
.bv-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1.25rem;
  margin-top: 3.5rem;
  padding: 1.5rem;
  border-radius: 16px;
  background: linear-gradient(160deg, rgba(20, 35, 55, 0.96), rgba(13, 24, 38, 0.96));
  border: 1px solid rgba(86, 150, 255, 0.22);
  box-shadow: 0 24px 50px -20px rgba(2, 8, 20, 0.55);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
}
@media (min-width: 768px) {
  .bv-stats { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}
.bv-stat { text-align: center; }
.bv-stat-value {
  font-size: 1.9rem;
  line-height: 1.1;
  font-weight: 800;
  color: #f1f5f9;
  font-variant-numeric: tabular-nums;
}
.bv-stat-value .bv-suffix { color: #34d399; }
.bv-stat-label {
  margin-top: 0.35rem;
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: #94a3b8;
}

/* ---------- Cards (features / articles) ---------- */
.bv-card {
  position: relative;
  border-radius: 16px;
  padding: 1.5rem;
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid rgba(148, 163, 184, 0.18);
  transition: transform 300ms ease, box-shadow 300ms ease, border-color 300ms ease;
}
.bv-card:hover {
  transform: translateY(-6px);
  border-color: rgba(33, 116, 234, 0.35);
  box-shadow:
    0 20px 40px -18px rgba(15, 23, 42, 0.25),
    0 0 0 1px rgba(33, 116, 234, 0.12);
}
.bv-card:hover svg:first-of-type { transform: translateY(-4px) scale(1.05); }
.bv-card > svg:first-of-type { transition: transform 300ms ease; }

/* ---------- CTA animated gradient ---------- */
.bv-cta {
  position: relative;
  overflow: hidden;
}
.bv-cta::before {
  content: "";
  position: absolute;
  inset: -40%;
  background:
    radial-gradient(circle at 20% 30%, rgba(33, 116, 234, 0.12), transparent 45%),
    radial-gradient(circle at 80% 70%, rgba(52, 211, 153, 0.12), transparent 45%);
  animation: bv-cta-swirl 16s ease-in-out infinite alternate;
  pointer-events: none;
}
@keyframes bv-cta-swirl {
  from { transform: rotate(0deg) scale(1); }
  to   { transform: rotate(8deg) scale(1.1); }
}

/* ---------- Reveal on scroll (progressive enhancement over AOS) ---------- */
.bv-reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 700ms cubic-bezier(0.16, 1, 0.3, 1), transform 700ms cubic-bezier(0.16, 1, 0.3, 1);
}
.bv-reveal.bv-in {
  opacity: 1;
  transform: none;
}

/* ---------- Reduced motion: switch everything off ---------- */
@media (prefers-reduced-motion: reduce) {
  .bv-aurora, .bv-float, .bv-gradient-text, .bv-cta::before, .bv-pulse-dot::after,
  .logo-carousel-track {
    animation: none !important;
  }
  .bv-tilt, .bv-btn-glow, .bv-btn-outline, .bv-card { transition: none !important; }
  .bv-reveal { opacity: 1; transform: none; transition: none; }
  #bv-particles { display: none; }
  .bv-progress { display: none; }
}