/* BillAlert PWA - Mobile-first, no frameworks */
:root {
  --bg: #F8F9FA;
  --primary: #1A56A0;
  --primary-dark: #134080;
  --success: #28A745;
  --warning: #FFC107;
  --danger: #DC3545;
  --text: #212529;
  --text-muted: #6C757D;
  --border: #DEE2E6;
  --card-bg: #FFFFFF;
  --radius: 10px;
  --shadow: 0 2px 8px rgba(0,0,0,0.10);
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { font-size: 16px; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100dvh;
  -webkit-tap-highlight-color: transparent;
}

/* ── Layout ── */
.app-header {
  background: var(--primary);
  color: #fff;
  padding: 1rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 6px rgba(0,0,0,0.2);
}
.app-header h1 { font-size: 1.15rem; font-weight: 700; letter-spacing: 0.01em; }
.app-header button { background: none; border: none; color: #fff; cursor: pointer; font-size: 1.4rem; padding: 0.25rem; }

main { padding: 1rem; max-width: 600px; margin: 0 auto; }

/* ── Screens ── */
.screen { display: none; }
.screen.active { display: block; }

/* ── Login ── */
.login-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 2rem 1.5rem;
  margin-top: 2rem;
}
.login-card .logo {
  text-align: center;
  font-size: 3rem;
  margin-bottom: 0.5rem;
}
.login-card h2 { text-align: center; color: var(--primary); margin-bottom: 1.5rem; font-size: 1.2rem; }

/* ── Forms ── */
.form-group { margin-bottom: 1rem; }
.form-group label { display: block; font-size: 0.85rem; font-weight: 600; color: var(--text-muted); margin-bottom: 0.3rem; }
.form-group input, .form-group select {
  width: 100%;
  padding: 0.7rem 0.9rem;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  font-size: 1rem;
  background: var(--bg);
  color: var(--text);
  transition: border-color 0.15s;
}
.form-group input:focus, .form-group select:focus {
  outline: none;
  border-color: var(--primary);
}

/* ── Buttons ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.75rem 1.25rem;
  border: none;
  border-radius: var(--radius);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: opacity 0.15s, transform 0.1s;
  text-decoration: none;
  width: 100%;
}
.btn:active { transform: scale(0.97); }
.btn:disabled { opacity: 0.55; cursor: not-allowed; }

.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-success { background: var(--success); color: #fff; }
.btn-warning { background: var(--warning); color: #212529; }
.btn-danger  { background: var(--danger); color: #fff; }
.btn-outline {
  background: transparent;
  color: var(--primary);
  border: 1.5px solid var(--primary);
}
.btn-sm { padding: 0.5rem 0.9rem; font-size: 0.85rem; width: auto; }
.btn-row { display: flex; gap: 0.5rem; margin-top: 0.75rem; }
.btn-row .btn { flex: 1; }

/* ── Cards ── */
.card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1rem 1.1rem;
  margin-bottom: 0.85rem;
}

.service-card { border-left: 4px solid var(--border); }
.service-card.status-pending  { border-left-color: var(--warning); }
.service-card.status-paid     { border-left-color: var(--success); }
.service-card.status-overdue  { border-left-color: var(--danger); }

.service-name { font-weight: 700; font-size: 1rem; }
.service-meta { display: flex; gap: 1rem; font-size: 0.82rem; color: var(--text-muted); margin-top: 0.2rem; flex-wrap: wrap; }
.service-amount { font-size: 1.35rem; font-weight: 700; color: var(--primary); margin-top: 0.4rem; }

.badge {
  display: inline-block;
  padding: 0.15rem 0.55rem;
  border-radius: 20px;
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
.badge-pending  { background: #FFF3CD; color: #856404; }
.badge-paid     { background: #D1E7DD; color: #0F5132; }
.badge-overdue  { background: #F8D7DA; color: #842029; }

.days-chip {
  font-size: 0.8rem;
  font-weight: 600;
  padding: 0.2rem 0.6rem;
  border-radius: 20px;
  background: var(--bg);
  border: 1px solid var(--border);
}
.days-chip.urgent { background: #F8D7DA; border-color: var(--danger); color: var(--danger); }
.days-chip.soon   { background: #FFF3CD; border-color: var(--warning); color: #856404; }
.days-chip.ok     { background: #D1E7DD; border-color: var(--success); color: #0F5132; }

/* ── Section header ── */
.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin: 1rem 0 0.6rem;
}
.section-header h2 { font-size: 1rem; font-weight: 700; color: var(--text-muted); text-transform: uppercase; letter-spacing: 0.05em; }

/* ── Empty state ── */
.empty-state {
  text-align: center;
  padding: 2.5rem 1rem;
  color: var(--text-muted);
}
.empty-state .icon { font-size: 3rem; margin-bottom: 0.5rem; }
.empty-state p { font-size: 0.95rem; }

/* ── Modal / Confirm dialog ── */
.modal-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.45);
  z-index: 200;
  align-items: flex-end;
  justify-content: center;
}
.modal-overlay.active { display: flex; }
.modal {
  background: var(--card-bg);
  border-radius: var(--radius) var(--radius) 0 0;
  padding: 1.5rem 1.25rem 2rem;
  width: 100%;
  max-width: 480px;
  box-shadow: 0 -4px 20px rgba(0,0,0,0.15);
  animation: slideUp 0.2s ease;
}
@keyframes slideUp { from { transform: translateY(100%); } to { transform: translateY(0); } }
.modal h3 { font-size: 1.05rem; margin-bottom: 0.5rem; }
.modal p  { font-size: 0.9rem; color: var(--text-muted); margin-bottom: 1.25rem; }

/* ── Toast ── */
#toast {
  position: fixed;
  bottom: 1.5rem;
  left: 50%;
  transform: translateX(-50%) translateY(120%);
  background: #333;
  color: #fff;
  padding: 0.65rem 1.3rem;
  border-radius: 24px;
  font-size: 0.9rem;
  z-index: 300;
  transition: transform 0.25s ease;
  white-space: nowrap;
}
#toast.show { transform: translateX(-50%) translateY(0); }

/* ── Spinner ── */
.spinner {
  width: 36px; height: 36px;
  border: 4px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  margin: 2rem auto;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ── Error banner ── */
.error-banner {
  background: #F8D7DA;
  color: #842029;
  border-radius: var(--radius);
  padding: 0.75rem 1rem;
  font-size: 0.88rem;
  margin-bottom: 0.75rem;
  display: none;
}
.error-banner.active { display: block; }

/* ── Nav tabs ── */
.nav-tabs {
  display: flex;
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  margin-bottom: 1rem;
  overflow: hidden;
}
.nav-tab {
  flex: 1;
  padding: 0.7rem;
  text-align: center;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
  cursor: pointer;
  border: none;
  background: none;
  border-bottom: 3px solid transparent;
  transition: color 0.15s, border-color 0.15s;
}
.nav-tab.active { color: var(--primary); border-bottom-color: var(--primary); }

/* ── History ── */
.history-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.6rem 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.88rem;
}
.history-item:last-child { border-bottom: none; }

/* ── Responsive tweaks ── */
@media (min-width: 480px) {
  .btn-row .btn { max-width: 200px; }
}