:root {
  --bg-color: #0f172a;
  --surface-color: #1e293b;
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --accent: #38bdf8;
  --accent-glow: rgba(56, 189, 248, 0.5);
  --danger: #ef4444;
}

body {
  margin: 0;
  padding: 0;
  font-family: 'Inter', system-ui, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-main);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

header {
  padding: 2rem;
  background: rgba(30, 41, 59, 0.7);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  position: sticky;
  top: 0;
  z-index: 10;
}

h1 {
  margin: 0;
  font-size: 2.5rem;
  font-weight: 800;
  background: linear-gradient(135deg, #38bdf8, #818cf8);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  text-align: center;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem;
  flex: 1;
}

#billboards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

.card {
  background: var(--surface-color);
  border-radius: 16px;
  overflow: hidden;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1), 0 1px 3px rgba(0, 0, 0, 0.08);
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.3s ease;
  position: relative;
  display: flex;
  flex-direction: column;
}

.card:hover {
  transform: translateY(-8px);
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.3), 0 0 15px var(--accent-glow);
}

.card-img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.card-content {
  padding: 1.5rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.card-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 0 0 0.5rem 0;
  color: var(--text-main);
  line-height: 1.4;
}

.card-meta {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 1rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.badge {
  background: rgba(56, 189, 248, 0.1);
  color: var(--accent);
  padding: 0.25rem 0.75rem;
  border-radius: 9999px;
  font-size: 0.75rem;
  font-weight: 500;
  border: 1px solid rgba(56, 189, 248, 0.2);
}

.card-price {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent);
  margin-top: auto;
  padding-top: 1rem;
  border-top: 1px solid rgba(255,255,255,0.05);
}

.loading {
  text-align: center;
  padding: 4rem;
  font-size: 1.25rem;
  color: var(--accent);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

#error-msg {
  color: var(--danger);
  text-align: center;
  padding: 2rem;
  background: rgba(239, 68, 68, 0.1);
  border-radius: 8px;
  margin-top: 2rem;
  display: none;
}