:root {
  --color-primary: #1d4ed8;
  --color-primary-dark: #1e3a8a;
  --color-danger: #dc2626;
  --color-bg: #f1f5f9;
  --color-panel: #ffffff;
  --color-border: #e2e8f0;
  --color-text: #1e293b;
  --color-text-muted: #64748b;
  --radius: 10px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--color-bg);
  color: var(--color-text);
}

a { color: var(--color-primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.topbar {
  background: var(--color-primary-dark);
  color: #fff;
  padding: 14px 0;
}
.topbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.topbar-title { font-weight: 700; font-size: 1.15rem; }
.topbar-links a { color: #dbeafe; margin-left: 18px; font-size: 0.92rem; }
.topbar-links a:hover { color: #fff; }

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 20px;
}

.breadcrumb { margin: 20px 0 0; font-size: 0.92rem; }

.panel {
  background: var(--color-panel);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
  margin: 20px 0;
}
.panel h2 { margin-top: 0; }
.panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
  gap: 12px;
}
.panel-header h2 { margin: 0; }

.field { margin-bottom: 16px; }
.field label {
  display: block;
  font-size: 0.88rem;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--color-text-muted);
}
.field input {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  font-size: 1rem;
}
.field input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(29,78,216,0.15);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
@media (max-width: 560px) {
  .form-row { grid-template-columns: 1fr; }
}

.btn {
  display: inline-block;
  padding: 10px 18px;
  border-radius: 8px;
  border: 1px solid transparent;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  text-align: center;
}
.btn-primary { background: var(--color-primary); color: #fff; }
.btn-primary:hover { background: var(--color-primary-dark); text-decoration: none; }
.btn-outline { background: #fff; border-color: var(--color-border); color: var(--color-text); }
.btn-outline:hover { border-color: var(--color-primary); text-decoration: none; }
.btn-danger { background: #fff; border-color: var(--color-danger); color: var(--color-danger); }
.btn-danger:hover { background: var(--color-danger); color: #fff; text-decoration: none; }
.btn-block { width: 100%; }
.btn-sm { padding: 6px 12px; font-size: 0.85rem; }

.data-table-wrap { overflow-x: auto; }
.data-table { width: 100%; border-collapse: collapse; font-size: 0.94rem; }
.data-table th, .data-table td {
  padding: 10px 12px;
  text-align: left;
  border-bottom: 1px solid var(--color-border);
  white-space: nowrap;
}
.data-table th { color: var(--color-text-muted); font-size: 0.82rem; text-transform: uppercase; letter-spacing: 0.03em; }
.actions-cell { text-align: right; }

.badge {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 700;
}
.badge-overdue { background: #fee2e2; color: #b91c1c; }
.badge-soon { background: #fef3c7; color: #92400e; }
.badge-ok { background: #dcfce7; color: #15803d; }

.flash {
  padding: 12px 16px;
  border-radius: 8px;
  margin-bottom: 16px;
  font-size: 0.92rem;
}
.flash-success { background: #dcfce7; color: #15803d; }
.flash-error { background: #fee2e2; color: #b91c1c; }

.help-text { color: var(--color-text-muted); font-size: 0.9rem; margin-top: -6px; }
.empty-state { color: var(--color-text-muted); font-style: italic; padding: 12px 0; }

.login-shell {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, #1e3a8a, #1d4ed8);
  padding: 20px;
}
.login-card {
  background: #fff;
  border-radius: 14px;
  padding: 36px 32px;
  width: 100%;
  max-width: 380px;
  box-shadow: 0 20px 50px rgba(0,0,0,0.25);
}
.login-card h1 { margin: 0 0 4px; text-align: center; color: var(--color-primary-dark); }
.login-sub { text-align: center; color: var(--color-text-muted); margin: 0 0 24px; font-size: 0.9rem; }

.stat-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin: 20px 0;
}
@media (max-width: 620px) {
  .stat-row { grid-template-columns: 1fr; }
}
.stat-box {
  background: var(--color-panel);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 18px;
  text-align: center;
}
.stat-value { font-size: 1.6rem; font-weight: 700; color: var(--color-primary-dark); }
.stat-label { font-size: 0.82rem; color: var(--color-text-muted); text-transform: uppercase; letter-spacing: 0.03em; margin-top: 4px; }

.payment-history { margin-top: 8px; }

.quickpay-form {
  display: flex;
  align-items: center;
  gap: 6px;
}
.quickpay-input {
  width: 90px;
  padding: 6px 8px;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  font-size: 0.88rem;
}
.quickpay-input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(29,78,216,0.15);
}