/* ============================================================================
   ZIE POS — Base styles
   Design philosophy:
   - Mobile-first (POS tablets primarily)
   - Tap targets >= 48px (POS environment)
   - High contrast (warehouse lighting)
   - Thai-readable line heights
   ============================================================================ */

:root {
  --color-bg: #0f172a;
  --color-bg-card: #1e293b;
  --color-bg-input: #334155;
  --color-text: #f8fafc;
  --color-text-muted: #94a3b8;
  --color-border: #475569;
  --color-primary: #3b82f6;
  --color-primary-hover: #2563eb;
  --color-success: #10b981;
  --color-warn: #f59e0b;
  --color-danger: #ef4444;
  --color-info: #06b6d4;

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;

  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 40px;

  --font-base: 16px;
  --font-lg: 20px;
  --font-xl: 28px;
  --line-height: 1.6;

  --tap-target: 48px;
}

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

html {
  font-size: var(--font-base);
  line-height: var(--line-height);
}

body {
  font-family:
    "Sarabun", "Noto Sans Thai", -apple-system, BlinkMacSystemFont,
    "Segoe UI", Roboto, sans-serif;
  background: var(--color-bg);
  color: var(--color-text);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -webkit-tap-highlight-color: transparent;
}

button,
input,
select,
textarea {
  font: inherit;
  color: inherit;
}

button {
  cursor: pointer;
  background: none;
  border: none;
  min-height: var(--tap-target);
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--radius-md);
  transition: background 0.15s, transform 0.05s;
}

button:active {
  transform: scale(0.98);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  font-weight: 600;
  font-size: var(--font-lg);
}

.btn-primary {
  background: var(--color-primary);
  color: white;
}

.btn-primary:hover {
  background: var(--color-primary-hover);
}

.btn-primary:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-secondary {
  background: var(--color-bg-input);
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

input,
select,
textarea {
  width: 100%;
  padding: var(--space-md);
  background: var(--color-bg-input);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text);
  min-height: var(--tap-target);
}

input:focus,
select:focus,
textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.3);
}

label {
  display: block;
  font-weight: 600;
  margin-bottom: var(--space-xs);
  color: var(--color-text-muted);
}

.card {
  background: var(--color-bg-card);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.3);
}

.field {
  margin-bottom: var(--space-md);
}

/* Login layout */
.center-screen {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-md);
}

.login-card {
  width: 100%;
  max-width: 400px;
}

.login-card h1 {
  font-size: var(--font-xl);
  margin-bottom: var(--space-xs);
  text-align: center;
}

.login-card .subtitle {
  text-align: center;
  color: var(--color-text-muted);
  margin-bottom: var(--space-lg);
}

.alert {
  padding: var(--space-md);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-md);
  font-weight: 500;
}

.alert-error {
  background: rgba(239, 68, 68, 0.15);
  border: 1px solid var(--color-danger);
  color: #fca5a5;
}

.alert-success {
  background: rgba(16, 185, 129, 0.15);
  border: 1px solid var(--color-success);
  color: #6ee7b7;
}

.hidden {
  display: none !important;
}

.text-center {
  text-align: center;
}

.lang-switch {
  position: fixed;
  top: var(--space-md);
  right: var(--space-md);
  display: flex;
  gap: var(--space-xs);
}

.lang-switch button {
  min-height: 36px;
  padding: var(--space-xs) var(--space-md);
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-size: 14px;
}

.lang-switch button.active {
  background: var(--color-primary);
  border-color: var(--color-primary);
}

/* Loading spinner */
.spinner {
  width: 20px;
  height: 20px;
  border: 3px solid rgba(255, 255, 255, 0.3);
  border-top-color: white;
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
  display: inline-block;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* Responsive: larger screens */
@media (min-width: 768px) {
  :root {
    --font-base: 17px;
  }
}