:root {
  --primary: #1976d2;
  --primary-hover: #1565c0;
  --primary-light: #e3f2fd;
  --success: #2e7d32;
  --success-bg: #e8f5e9;
  --danger: #d32f2f;
  --danger-bg: #ffebee;
  --warning: #ed6c02;
  --warning-bg: #fff3e0;
  --bg-color: #f8fafc;
  --card-bg: #ffffff;
  --text-main: #0f172a;
  --text-muted: #64748b;
  --border-color: #e2e8f0;
  --border-radius: 12px;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Sarabun", Helvetica, Arial, sans-serif;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-color);
  color: var(--text-main);
  line-height: 1.5;
  font-size: 16px;
  min-height: 100vh;
}

/* Header & Navigation */
header {
  background: #ffffff;
  border-bottom: 1px solid var(--border-color);
  padding: 12px 16px;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

.header-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
}

.brand-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--primary);
  display: flex;
  align-items: center;
  gap: 8px;
}

.domain-pill {
  font-size: 0.75rem;
  background: var(--primary-light);
  color: var(--primary);
  padding: 3px 8px;
  border-radius: 9999px;
  font-weight: 600;
  text-decoration: none;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.btn-lang {
  background: #f1f5f9;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 6px 12px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  min-height: 40px;
}

.nav-tabs {
  display: flex;
  gap: 8px;
  overflow-x: auto;
  padding-bottom: 4px;
}

.nav-btn {
  background: none;
  border: none;
  padding: 8px 14px;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-muted);
  border-radius: 8px;
  cursor: pointer;
  white-space: nowrap;
  min-height: 48px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.nav-btn.active {
  background: var(--primary-light);
  color: var(--primary);
}

/* Container */
.container {
  max-width: 1024px;
  margin: 0 auto;
  padding: 16px;
}

/* Step Wizard Progress */
.wizard-progress {
  display: flex;
  justify-content: space-between;
  margin-bottom: 20px;
  position: relative;
}

.wizard-progress::before {
  content: "";
  position: absolute;
  top: 18px;
  left: 30px;
  right: 30px;
  height: 3px;
  background: var(--border-color);
  z-index: 1;
}

.step-node {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  align-items: center;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
  width: 25%;
  text-align: center;
}

.step-circle {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: #ffffff;
  border: 2px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 6px;
  font-weight: 700;
  transition: all 0.2s ease;
}

.step-node.active .step-circle {
  border-color: var(--primary);
  background: var(--primary);
  color: #ffffff;
}

.step-node.completed .step-circle {
  border-color: var(--success);
  background: var(--success);
  color: #ffffff;
}

/* Cards & Sections */
.card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: 20px;
  margin-bottom: 16px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.03);
}

.card-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

/* Form Controls */
.form-group {
  margin-bottom: 16px;
}

.form-label {
  display: block;
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text-main);
}

.form-select, .form-input {
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  font-size: 1rem;
  background: #ffffff;
  color: var(--text-main);
  min-height: 48px;
}

.form-select:focus, .form-input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(25, 118, 210, 0.15);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 20px;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  min-height: 48px;
  text-decoration: none;
  transition: background 0.15s ease;
}

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

.btn-success {
  background: var(--success);
  color: #ffffff;
}

.btn-danger {
  background: var(--danger);
  color: #ffffff;
}

.btn-outline {
  background: transparent;
  border: 1px solid var(--border-color);
  color: var(--text-main);
}
.btn-outline:hover {
  background: #f1f5f9;
}

.btn-block {
  width: 100%;
}

.btn-large {
  min-height: 56px;
  font-size: 1.15rem;
}

/* Instruction Banners */
.instruction-banner {
  background: var(--primary-light);
  border-left: 4px solid var(--primary);
  padding: 12px 16px;
  border-radius: 0 8px 8px 0;
  margin-bottom: 16px;
  font-size: 0.95rem;
  display: flex;
  align-items: center;
  gap: 12px;
}

/* Status Badges */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 10px;
  border-radius: 9999px;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
}

.badge-pass {
  background: var(--success-bg);
  color: var(--success);
}
.badge-ng {
  background: var(--danger-bg);
  color: var(--danger);
}
.badge-hold {
  background: var(--warning-bg);
  color: var(--warning);
}

/* Camera & Capture Section */
.camera-container {
  position: relative;
  width: 100%;
  max-width: 500px;
  margin: 0 auto 16px auto;
  border-radius: 12px;
  overflow: hidden;
  background: #000000;
  aspect-ratio: 4 / 3;
}

#camera-video, #captured-preview {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.camera-guide-box {
  position: absolute;
  top: 15%;
  left: 10%;
  right: 10%;
  bottom: 15%;
  border: 2px dashed rgba(255, 255, 255, 0.8);
  border-radius: 8px;
  pointer-events: none;
  box-shadow: 0 0 0 9999px rgba(0, 0, 0, 0.4);
}

.camera-guide-hint {
  position: absolute;
  bottom: 8px;
  left: 0;
  right: 0;
  text-align: center;
  color: #ffffff;
  font-size: 0.8rem;
  background: rgba(0,0,0,0.6);
  padding: 4px;
}

/* Recognition Display */
.reading-display-box {
  background: #0f172a;
  color: #38bdf8;
  padding: 20px;
  border-radius: 12px;
  text-align: center;
  margin-bottom: 16px;
  font-family: monospace, monospace;
}

.reading-val {
  font-size: 2.75rem;
  font-weight: 700;
  letter-spacing: 2px;
  color: #38ef7d;
}

.reading-unit {
  font-size: 1.25rem;
  color: #94a3b8;
  margin-left: 6px;
}

.reading-meta {
  margin-top: 8px;
  font-size: 0.85rem;
  color: #94a3b8;
}

/* Result Overview Card */
.result-banner {
  padding: 24px;
  border-radius: 12px;
  text-align: center;
  margin-bottom: 20px;
}

.result-banner.pass {
  background: var(--success-bg);
  border: 2px solid var(--success);
  color: var(--success);
}

.result-banner.ng {
  background: var(--danger-bg);
  border: 2px solid var(--danger);
  color: var(--danger);
}

.result-banner.hold {
  background: var(--warning-bg);
  border: 2px solid var(--warning);
  color: var(--warning);
}

.result-banner-title {
  font-size: 2rem;
  font-weight: 800;
  margin-bottom: 8px;
}

.result-banner-desc {
  font-size: 1.05rem;
  color: var(--text-main);
  margin-bottom: 8px;
}

.result-banner-action {
  font-size: 0.95rem;
  font-weight: 600;
}

/* Sample Grid */
.sample-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
  margin-bottom: 16px;
}

.sample-card {
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 12px;
  background: #ffffff;
}

/* Tables for QA Desk */
.table-responsive {
  width: 100%;
  overflow-x: auto;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.data-table th, .data-table td {
  padding: 10px 12px;
  border-bottom: 1px solid var(--border-color);
  text-align: left;
}

.data-table th {
  background: #f8fafc;
  font-weight: 700;
  color: var(--text-muted);
}

/* Tablet & Desktop Layout (>= 768px) */
@media (min-width: 768px) {
  .tablet-split {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    align-items: start;
  }
  .sample-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* Modals */
.modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: 16px;
}

.modal-content {
  background: #ffffff;
  border-radius: 12px;
  max-width: 550px;
  width: 100%;
  padding: 24px;
  box-shadow: 0 10px 25px rgba(0,0,0,0.15);
  max-height: 90vh;
  overflow-y: auto;
}