/* ═══════════════════════════════════════════════════════════
   FON ANIMATSIYASI — Digital Academy brend ranglari + logo
   ───────────────────────────────────────────────────────────
   Ishlatilishi (body ichida, eng birinchi element):

     <div class="bg" aria-hidden="true">
       <div class="bg__orb bg__orb--1"></div>
       <div class="bg__orb bg__orb--2"></div>
       <div class="bg__orb bg__orb--3"></div>
       <div class="bg__grid"></div>
       <div class="bg__logo"></div>
       <canvas class="bg__net" id="bgNet"></canvas>
     </div>

   Variantlar (body klassi):
     .bg-soft   → yumshoq (dashboard, test, natija) — o'qishga xalaqit bermaydi
     .bg-hero   → to'yingan (login sahifasi)

   Tejamkorlik: faqat transform/opacity animatsiya qilinadi (GPU),
   tab fonga o'tsa canvas to'xtaydi, .no-anim da hammasi qotadi.
   ═══════════════════════════════════════════════════════════ */

.bg {
  position: fixed;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
  background: var(--bg-base, var(--paper));
  contain: strict;
}

/* ── Asosiy fon ranglari ──────────────────────────────── */

.bg-soft .bg {
  --bg-base: radial-gradient(ellipse 120% 80% at 50% -10%,
              var(--brand-50) 0%, var(--paper) 55%);
}
.bg-hero .bg {
  --bg-base: radial-gradient(ellipse 100% 90% at 50% 35%,
              var(--brand-600) 0%, var(--brand-900) 45%, var(--brand-950) 100%);
}

[data-theme="dark"].bg-soft .bg,
[data-theme="dark"] .bg-soft .bg {
  --bg-base: radial-gradient(ellipse 120% 80% at 50% -10%,
              #142a42 0%, #0d1420 55%);
}

/* ── Suzuvchi yorug'lik sharlari ──────────────────────── */

.bg__orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(70px);
  will-change: transform;
  opacity: .5;
}

.bg-soft .bg__orb { opacity: .30; }
.bg-hero .bg__orb { opacity: .48; }

.bg__orb--1 {
  width: 46vmax; height: 46vmax;
  left: -12vmax; top: -14vmax;
  background: radial-gradient(circle, var(--brand-400) 0%, transparent 68%);
  animation: bg-drift-1 26s ease-in-out infinite;
}
.bg__orb--2 {
  width: 40vmax; height: 40vmax;
  right: -12vmax; top: 18vmax;
  background: radial-gradient(circle, var(--brand-500) 0%, transparent 68%);
  animation: bg-drift-2 32s ease-in-out infinite;
}
.bg__orb--3 {
  width: 52vmax; height: 52vmax;
  left: 28vmax; bottom: -26vmax;
  background: radial-gradient(circle, var(--brand-300) 0%, transparent 70%);
  animation: bg-drift-3 38s ease-in-out infinite;
}

@keyframes bg-drift-1 {
  0%, 100% { transform: translate3d(0, 0, 0) scale(1); }
  33%      { transform: translate3d(7vmax, 5vmax, 0) scale(1.12); }
  66%      { transform: translate3d(3vmax, 10vmax, 0) scale(.94); }
}
@keyframes bg-drift-2 {
  0%, 100% { transform: translate3d(0, 0, 0) scale(1); }
  40%      { transform: translate3d(-9vmax, 7vmax, 0) scale(1.16); }
  75%      { transform: translate3d(-4vmax, -5vmax, 0) scale(.9); }
}
@keyframes bg-drift-3 {
  0%, 100% { transform: translate3d(0, 0, 0) scale(1); }
  50%      { transform: translate3d(-11vmax, -8vmax, 0) scale(1.1); }
}

/* ── Nozik to'r (texnologik ohang) ────────────────────── */

.bg__grid {
  position: absolute;
  inset: -50%;
  background-image:
    linear-gradient(var(--bg-line, rgba(16,96,184,.10)) 1px, transparent 1px),
    linear-gradient(90deg, var(--bg-line, rgba(16,96,184,.10)) 1px, transparent 1px);
  background-size: 54px 54px;
  mask-image: radial-gradient(ellipse 46% 46% at 50% 50%, #000 0%, transparent 78%);
  -webkit-mask-image: radial-gradient(ellipse 46% 46% at 50% 50%, #000 0%, transparent 78%);
  animation: bg-grid-pan 60s linear infinite;
  will-change: transform;
}
.bg-soft .bg__grid { opacity: .55; }
.bg-hero .bg__grid { --bg-line: rgba(255,255,255,.13); opacity: .8; }
[data-theme="dark"] .bg__grid { --bg-line: rgba(91,154,232,.11); }

@keyframes bg-grid-pan {
  to { transform: translate3d(54px, 54px, 0); }
}

/* ── Logo — sekin aylanuvchi suv belgisi ──────────────── */

.bg__logo {
  position: absolute;
  left: 50%; top: 50%;
  width: min(62vmin, 620px);
  aspect-ratio: 1;
  margin: -31vmin 0 0 -31vmin;
  background: url("/img/logo.png") center/contain no-repeat;
  will-change: transform, opacity;
  animation: bg-logo-breathe 18s ease-in-out infinite;
}
.bg-soft .bg__logo { opacity: .035; }
.bg-hero .bg__logo { opacity: .09; }
[data-theme="dark"] .bg__logo { opacity: .05; }

@keyframes bg-logo-breathe {
  0%, 100% { transform: scale(1) rotate(0deg); }
  50%      { transform: scale(1.06) rotate(4deg); }
}

/* Logo aylanasi atrofidagi puls halqasi (faqat hero) */
.bg-hero .bg__logo::after {
  content: "";
  position: absolute;
  inset: -6%;
  border: 1px solid rgba(255,255,255,.22);
  border-radius: 50%;
  animation: bg-ring-pulse 4.5s ease-out infinite;
}
@keyframes bg-ring-pulse {
  0%   { transform: scale(.92); opacity: .55; }
  70%  { transform: scale(1.14); opacity: 0; }
  100% { transform: scale(1.14); opacity: 0; }
}

/* ── Zarrachalar to'ri (canvas, background.js chizadi) ── */

.bg__net {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}
.bg-soft .bg__net { opacity: .34; }
.bg-hero .bg__net { opacity: .60; }

/* ── Hero sahifada matn oq bo'lsin ────────────────────── */

.bg-hero { color: #fff; }

/* ── Tejamkorlik va imkoniyatlar ──────────────────────── */

/* Animatsiya o'chirilgan bo'lsa — statik, lekin chiroyli fon qoladi */
.no-anim .bg__orb,
.no-anim .bg__grid,
.no-anim .bg__logo,
.no-anim .bg__logo::after {
  animation: none !important;
}
.no-anim .bg__net { display: none; }

@media (prefers-reduced-motion: reduce) {
  .bg__orb, .bg__grid, .bg__logo, .bg__logo::after { animation: none !important; }
  .bg__net { display: none; }
}

/* Kichik ekran / kuchsiz qurilma — blur qimmat, yengillashtiramiz */
@media (max-width: 760px) {
  .bg__orb { filter: blur(48px); }
  .bg__net { display: none; }
  .bg__grid { background-size: 40px 40px; }
}

/* Chop etishda fon ko'rinmasin */
@media print {
  .bg { display: none !important; }
}