/* SBC-branded prototype - Sustainability Singapore 2026 */
:root {
  --sbc-dark: #0a1628;
  --sbc-teal: #00a896;
  --sbc-teal-light: #00c9b7;
  --sbc-navy: #0d3b4c;
  --sbc-white: #ffffff;
  --sbc-gray-100: #f5f7fa;
  --sbc-gray-200: #e8ecf1;
  --sbc-gray-500: #6b7280;
  --sbc-gray-700: #374151;
  --sbc-gray-900: #111827;
  --sbc-success: #10b981;
  --sbc-warning: #f59e0b;
  --sbc-danger: #ef4444;
  --shadow: 0 1px 3px rgba(0,0,0,.08);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,.1), 0 2px 4px -2px rgba(0,0,0,.1);
  --radius: 8px;
  --radius-lg: 12px;
}

* { box-sizing: border-box; }
body { margin: 0; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Inter', sans-serif; color: var(--sbc-gray-900); background: var(--sbc-gray-100); line-height: 1.5; }

/* App chrome (screens 1-4) */
.app-header {
  background: var(--sbc-dark);
  color: var(--sbc-white);
  padding: 0.75rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  box-shadow: var(--shadow-md);
}
.app-header a { color: var(--sbc-white); text-decoration: none; font-weight: 500; }
.app-header a:hover { color: var(--sbc-teal-light); }
.app-logo { font-weight: 700; font-size: 1.1rem; display: flex; align-items: center; gap: 0.5rem; }
.app-logo img { height: 28px; width: auto; display: block; }
.app-nav { display: flex; gap: 1.25rem; font-size: 0.9rem; }
.app-nav a.active { color: var(--sbc-teal-light); }
.app-main { max-width: 1200px; margin: 0 auto; padding: 1.5rem; }

/* Cards */
.card {
  background: var(--sbc-white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  padding: 1.25rem;
  margin-bottom: 1rem;
}
.card-title { font-size: 1rem; font-weight: 600; margin: 0 0 0.75rem 0; color: var(--sbc-gray-900); }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: var(--radius);
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: background .2s, color .2s;
}
.btn-primary { background: var(--sbc-teal); color: var(--sbc-white); }
.btn-primary:hover { background: #008f80; }
.btn-secondary { background: var(--sbc-gray-200); color: var(--sbc-gray-700); }
.btn-secondary:hover { background: var(--sbc-gray-500); color: var(--sbc-white); }
.btn-outline { background: transparent; border: 2px solid var(--sbc-teal); color: var(--sbc-teal); }
.btn-outline:hover { background: var(--sbc-teal); color: var(--sbc-white); }

/* Badges & pills */
.badge { display: inline-block; padding: 0.25rem 0.5rem; font-size: 0.75rem; font-weight: 600; border-radius: 9999px; }
.badge-success { background: #d1fae5; color: #065f46; }
.badge-warning { background: #fef3c7; color: #92400e; }
.badge-info { background: #dbeafe; color: #1e40af; }
.badge-neutral { background: var(--sbc-gray-200); color: var(--sbc-gray-700); }
.badge-danger { background: #fee2e2; color: #991b1b; }

/* Progress */
.progress-bar {
  height: 8px;
  background: var(--sbc-gray-200);
  border-radius: 9999px;
  overflow: hidden;
}
.progress-fill { height: 100%; background: var(--sbc-teal); border-radius: 9999px; transition: width .3s; }

/* Utility */
.text-muted { color: var(--sbc-gray-500); font-size: 0.875rem; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mb-2 { margin-bottom: 1rem; }
.flex { display: flex; }
.gap-2 { gap: 0.5rem; }
.gap-4 { gap: 1rem; }
.items-center { align-items: center; }
.w-full { width: 100%; }

/* Responsive: mobile (<640px), tablet (640–1024px), laptop (1024px+) */
@media (max-width: 1024px) {
  .app-main { padding: 1rem; }
  .app-header { padding: 0.75rem 1rem; }
  .app-nav { gap: 0.75rem; font-size: 0.85rem; }
}
@media (max-width: 768px) {
  .app-header { flex-wrap: wrap; gap: 0.75rem; }
  .app-nav { width: 100%; flex-wrap: wrap; gap: 0.5rem; }
  .app-nav a { padding: 0.5rem 0; }
  .app-logo img { height: 24px; }
  .app-main { padding: 0.75rem 1rem; }
}
@media (max-width: 640px) {
  .app-header { padding: 0.5rem 0.75rem; }
  .app-nav { font-size: 0.8rem; gap: 0.5rem; }
  .app-main { padding: 0.5rem 0.75rem; }
  .card { padding: 1rem; }
}