/* =============================================
   iTOPIK Loader System
   Preloader · Top Loading Bar · Skeleton Screens
   ============================================= */

/* ── Preloader ─────────────────────────────── */
#preloader {
  position: fixed;
  inset: 0;
  z-index: 999999;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: #ffffff;
  transition: opacity 0.5s ease, transform 0.5s ease;
}
#preloader.hide {
  opacity: 0;
  transform: scale(0.95);
  pointer-events: none;
}
#preloader.removed {
  display: none;
}

.preloader-logo {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100px;
  height: 100px;
}

.preloader-ring {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 3px solid transparent;
  border-top-color: #0EA5E9;
  border-right-color: #6366F1;
  animation: preloaderSpin 1s cubic-bezier(0.4, 0, 0.2, 1) infinite;
}
.preloader-ring-2 {
  position: absolute;
  inset: 6px;
  border-radius: 50%;
  border: 3px solid transparent;
  border-bottom-color: #0EA5E9;
  border-left-color: #6366F1;
  animation: preloaderSpin 1.4s cubic-bezier(0.4, 0, 0.2, 1) infinite reverse;
}

.preloader-text {
  font-family: 'Inter', sans-serif;
  font-size: 28px;
  font-weight: 800;
  letter-spacing: -0.5px;
  z-index: 1;
}
.preloader-text .i-light {
  color: #0EA5E9;
  font-weight: 300;
}
.preloader-text .topik-grad {
  background: linear-gradient(135deg, #0EA5E9, #6366F1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.preloader-dots {
  display: flex;
  gap: 6px;
  margin-top: 24px;
}
.preloader-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #0EA5E9;
  animation: dotBounce 1.2s ease-in-out infinite;
}
.preloader-dot:nth-child(2) { animation-delay: 0.15s; }
.preloader-dot:nth-child(3) { animation-delay: 0.3s; }

/* ── Top Loading Bar ───────────────────────── */
#top-loader {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0%;
  z-index: 99999;
  background: linear-gradient(90deg, #0EA5E9, #6366F1, #0EA5E9);
  background-size: 200% 100%;
  animation: loaderShimmer 1.5s linear infinite;
  transition: width 0.3s ease;
  opacity: 0;
  pointer-events: none;
}
#top-loader.active {
  opacity: 1;
}
#top-loader.complete {
  opacity: 0;
  transition: opacity 0.3s ease 0.2s, width 0.1s ease;
}

/* ── Skeleton Screens ──────────────────────── */
@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.skeleton {
  background: linear-gradient(90deg, #E2E8F0 25%, #F1F5F9 50%, #E2E8F0 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s ease-in-out infinite;
  border-radius: 6px;
}

.skeleton-text {
  height: 14px;
  border-radius: 4px;
  width: 100%;
}
.skeleton-text.w-75 { width: 75%; }
.skeleton-text.w-50 { width: 50%; }
.skeleton-text.w-60 { width: 60%; }
.skeleton-text.w-40 { width: 40%; }
.skeleton-text.w-30 { width: 30%; }
.skeleton-text.w-25 { width: 25%; }

.skeleton-title {
  height: 24px;
  border-radius: 6px;
  width: 60%;
  margin-bottom: 12px;
}

.skeleton-card {
  border-radius: 16px;
  padding: 20px;
}
.skeleton-card .skeleton + .skeleton {
  margin-top: 10px;
}

.skeleton-avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  flex-shrink: 0;
}
.skeleton-avatar.sm { width: 36px; height: 36px; }
.skeleton-avatar.lg { width: 64px; height: 64px; }

.skeleton-button {
  height: 40px;
  border-radius: 8px;
  width: 120px;
}

.skeleton-row {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 0;
}
.skeleton-row + .skeleton-row {
  border-top: 1px solid #F1F5F9;
}

/* ── Keyframes ─────────────────────────────── */
@keyframes preloaderSpin {
  to { transform: rotate(360deg); }
}

@keyframes dotBounce {
  0%, 80%, 100% { transform: scale(0.6); opacity: 0.4; }
  40% { transform: scale(1); opacity: 1; }
}

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