/* Global Vars & Reset */
:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --success: #059669;
  --error: #dc2626;
  --bg: #f8fafc;
  --surface: #ffffff;
  --text-main: #0f172a;
  --text-muted: #64748b;
  --border: #e2e8f0;
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
  --radius: 12px;
  --font-family: 'Inter', system-ui, -apple-system, sans-serif;
}

* { box-sizing: border-box; touch-action: manipulation; }
body {
  margin: 0;
  padding: 0;
  font-family: var(--font-family);
  background: var(--bg);
  color: var(--text-main);
  height: 100vh;
  display: flex;
  flex-direction: column;
}

h1, h2, h3, p { margin: 0; }

/* Layout Utilities */
.container {
  max-width: 480px; /* Mobile focused max width */
  margin: 0 auto;
  padding: 20px;
  width: 100%;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 24px;
}
.brand {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
  letter-spacing: -0.025em;
}
.nav-link {
  color: var(--primary);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.9rem;
}

/* Card Inputs */
.input-group {
  margin-bottom: 24px;
}
.label {
  display: block;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-muted);
  margin-bottom: 8px;
}
.input-lg {
  width: 100%;
  padding: 16px;
  font-size: 1.5rem;
  text-align: center;
  border: 2px solid var(--border);
  border-radius: var(--radius);
  outline: none;
  font-weight: 600;
  transition: all 0.2s;
  background: var(--surface);
  color: var(--text-main);
}
.input-lg:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.1);
}

/* Session Toggles */
.session-toggle {
  display: flex;
  background: var(--surface);
  padding: 4px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  margin-bottom: 24px;
}
.session-opt {
  flex: 1;
  text-align: center;
  padding: 10px;
  border-radius: calc(var(--radius) - 4px);
  font-weight: 600;
  font-size: 0.9rem;
  cursor: pointer;
  transition: all 0.2s;
  color: var(--text-muted);
}
.session-opt.active {
  background: var(--primary);
  color: white;
  box-shadow: var(--shadow-sm);
}

/* Action Button */
.btn-primary {
  width: 100%;
  padding: 18px;
  background: var(--text-main); /* Trendy black button */
  color: white;
  border: none;
  border-radius: var(--radius);
  font-size: 1.1rem;
  font-weight: 600;
  cursor: pointer;
  box-shadow: var(--shadow-md);
  transition: transform 0.1s;
}
.btn-primary:active {
  transform: scale(0.98);
}

/* Result Card */
.result-card {
  margin-top: 24px;
  padding: 32px 20px;
  border-radius: var(--radius);
  text-align: center;
  display: none; /* Hidden by default */
  animation: slideUp 0.3s ease-out;
}
.result-card.success {
  background: #dcfce7;
  color: #166534;
  display: block;
}
.result-card.failure {
  background: #fee2e2;
  color: #991b1b;
  display: block;
}
.result-icon {
  font-size: 3rem;
  margin-bottom: 12px;
  display: block;
}
.result-title {
  font-size: 1.5rem;
  font-weight: 800;
  margin-bottom: 8px;
}
.result-reason {
  font-size: 1.1rem;
  opacity: 0.9;
}
.customer-badge {
    margin-top: 16px;
    display: inline-block;
    background: rgba(0,0,0,0.1);
    padding: 4px 12px;
    border-radius: 99px;
    font-size: 0.85rem;
    font-weight: 600;
}

@keyframes slideUp {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Admin Specific */
.admin-card {
    background: var(--surface);
    padding: 20px;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    margin-bottom: 16px;
}
.form-group { margin-bottom: 16px; }
.input-std {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 1rem;
}
.btn-sm {
    padding: 8px 16px;
    border-radius: 8px;
    background: var(--primary);
    color: white;
    border: none;
    font-weight: 500;
    cursor: pointer;
}