/* ==========================================================================
   Data Sprint - Training Portal Theme
   Author: Arki1 & Google Cloud Authorized Training Partner
   Design System: Material + Enterprise Clean Dashboard
   ========================================================================== */

:root {
  /* Brand Palette */
  --arki-blue: #3665ad;
  --arki-dark: #1e3a8a;
  --arki-navy: #0f172a;
  --arki-green: #61a229;
  
  --gcp-blue: #4285f4;
  --gcp-red: #ea4335;
  --gcp-yellow: #fbbc05;
  --gcp-green: #34a853;

  /* Neutrals */
  --bg-canvas: #f8fafc;
  --bg-surface: #ffffff;
  --bg-card: #ffffff;
  --bg-code: #0f172a;
  --bg-prompt: #f1f5f9;
  
  --border-subtle: #e2e8f0;
  --border-strong: #cbd5e1;
  --border-accent: #bfdbfe;

  --text-main: #0f172a;
  --text-muted: #64748b;
  --text-light: #94a3b8;
  --text-inverse: #ffffff;

  /* Accent states */
  --success-bg: #ecfdf5;
  --success-text: #065f46;
  --success-border: #a7f3d0;

  --warning-bg: #fffbeb;
  --warning-text: #92400e;
  --warning-border: #fde68a;

  --info-bg: #eff6ff;
  --info-text: #1e40af;
  --info-border: #bfdbfe;

  /* Shadows & Radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.04);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-canvas);
  color: var(--text-main);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header & Nav */
.header {
  background-color: var(--bg-surface);
  border-bottom: 1px solid var(--border-subtle);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

.header-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 10px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: relative;
  gap: 12px;
}

.header-fluid .header-container {
  max-width: 100%;
  padding: 10px 24px;
}

.auth-hidden,
#nav-auth-link.auth-hidden {
  display: none !important;
}

.header-left {
  display: flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}

.header-right {
  display: flex;
  align-items: center;
  gap: 10px;
}

.brand-group {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: inherit;
  min-width: 0;
}

.brand-logo-arki1 {
  height: 30px;
  width: auto;
  flex-shrink: 0;
}

.brand-divider {
  width: 1px;
  height: 22px;
  background-color: var(--border-strong);
  flex-shrink: 0;
}

.brand-logo-gcp {
  height: 22px;
  width: auto;
  flex-shrink: 0;
}

.brand-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--arki-dark);
  letter-spacing: -0.01em;
  white-space: nowrap;
}

/* Sidebar Toggle in Header (Deprecated, navigation moved out of top bar) */
.btn-sidebar-toggle {
  display: none !important;
}

/* Mobile & Split-Screen Menu Toggle */
.btn-menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 4px;
  width: 38px;
  height: 38px;
  background: transparent;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  cursor: pointer;
  padding: 8px 6px;
  flex-shrink: 0;
  transition: background-color 0.2s, border-color 0.2s;
}

.btn-menu-toggle:hover {
  background-color: var(--bg-canvas);
  border-color: var(--arki-blue);
}

.hamburger-bar {
  display: block;
  width: 20px;
  height: 2px;
  background-color: var(--text-main);
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.25s ease;
}

.btn-menu-toggle.active .hamburger-bar:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.btn-menu-toggle.active .hamburger-bar:nth-child(2) {
  opacity: 0;
}

.btn-menu-toggle.active .hamburger-bar:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.lang-select {
  padding: 6px 10px;
  font-size: 0.85rem;
  font-weight: 500;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  background-color: var(--bg-surface);
  color: var(--text-main);
  cursor: pointer;
  outline: none;
  transition: border-color 0.2s;
  white-space: nowrap;
}

.lang-select:focus {
  border-color: var(--gcp-blue);
}

.btn-nav {
  padding: 6px 12px;
  font-size: 0.85rem;
  font-weight: 600;
  text-decoration: none;
  border-radius: var(--radius-sm);
  transition: all 0.2s;
  white-space: nowrap;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
}

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

.btn-nav-outline:hover {
  background-color: var(--bg-canvas);
  border-color: var(--arki-blue);
  color: var(--arki-blue);
}

.btn-nav-primary {
  background-color: var(--arki-blue);
  color: var(--text-inverse);
  border: 1px solid var(--arki-blue);
}

.btn-nav-primary:hover {
  background-color: var(--arki-dark);
  border-color: var(--arki-dark);
}

/* Hero Section */
.hero-section {
  background: linear-gradient(135deg, #f0fdf4 0%, #eff6ff 100%);
  border-bottom: 1px solid var(--border-subtle);
  padding: 60px 24px;
  text-align: center;
}

.hero-container {
  max-width: 860px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 4px 12px;
  background-color: #dbeafe;
  color: var(--arki-dark);
  font-size: 0.8rem;
  font-weight: 600;
  border-radius: 9999px;
  margin-bottom: 20px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.hero-title {
  font-size: 2.5rem;
  font-weight: 800;
  line-height: 1.2;
  color: var(--arki-navy);
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.hero-subtitle {
  font-size: 1.15rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 32px;
}

/* Download Callout Card */
.starter-download-card {
  background-color: var(--bg-surface);
  border: 2px solid var(--gcp-blue);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-lg);
  max-width: 760px;
  margin: -30px auto 40px auto;
  position: relative;
  z-index: 10;
  text-align: left;
}

.download-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 20px;
  margin-bottom: 24px;
}

.download-title-group h3 {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--arki-navy);
  margin-bottom: 6px;
}

.download-title-group p {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.btn-download-primary {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background-color: var(--gcp-blue);
  color: var(--text-inverse);
  padding: 14px 28px;
  font-size: 1rem;
  font-weight: 700;
  border-radius: var(--radius-md);
  text-decoration: none;
  box-shadow: 0 4px 12px rgba(66, 133, 244, 0.3);
  transition: transform 0.15s, background-color 0.2s, box-shadow 0.2s;
}

.btn-download-primary:hover {
  background-color: #2b76f3;
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(66, 133, 244, 0.4);
}

.quickstart-steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
  border-top: 1px solid var(--border-subtle);
  padding-top: 20px;
}

.quickstart-step {
  display: flex;
  gap: 12px;
}

.step-num {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background-color: #eff6ff;
  color: var(--gcp-blue);
  font-weight: 700;
  font-size: 0.85rem;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.step-info h4 {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 4px;
}

.step-info p {
  font-size: 0.8rem;
  color: var(--text-muted);
  line-height: 1.4;
}

/* Main Hub Content */
.main-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 24px;
  flex: 1;
  width: 100%;
}

.section-header {
  text-align: center;
  margin-bottom: 36px;
}

.section-title {
  font-size: 1.85rem;
  font-weight: 800;
  color: var(--arki-navy);
  margin-bottom: 8px;
}

.section-subtitle {
  color: var(--text-muted);
  font-size: 1rem;
}

/* Lab Cards Grid */
.labs-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 24px;
  margin-bottom: 50px;
}

.labs-grid-setup {
  grid-template-columns: minmax(320px, 580px);
  margin-bottom: 32px;
}

.lab-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
  text-decoration: none;
  color: inherit;
}

.lab-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--border-accent);
}

.lab-card-badge {
  align-self: flex-start;
  padding: 4px 10px;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  border-radius: var(--radius-sm);
  margin-bottom: 14px;
}

.badge-module0 { background-color: #f1f5f9; color: #475569; }
.badge-challenge1 { background-color: #dbeafe; color: #1e40af; }
.badge-challenge2 { background-color: #dcfce7; color: #166534; }
.badge-challenge3 { background-color: #fef3c7; color: #92400e; }
.badge-capstone { background-color: #ede9fe; color: #5b21b6; }

.lab-card-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 10px;
  line-height: 1.3;
}

.lab-card-desc {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 20px;
  flex-grow: 1;
}

.lab-card-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-top: 1px solid var(--border-subtle);
  padding-top: 14px;
  font-size: 0.85rem;
}

.lab-meta {
  color: var(--text-muted);
  display: flex;
  gap: 12px;
}

.lab-link-text {
  font-weight: 600;
  color: var(--arki-blue);
  display: flex;
  align-items: center;
  gap: 4px;
}

/* Facilitator Slides Card */
.slides-banner {
  background: linear-gradient(135deg, #1e3a8a 0%, #0f172a 100%);
  border-radius: var(--radius-lg);
  padding: 32px;
  color: var(--text-inverse);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 24px;
  margin-bottom: 40px;
}

.slides-banner-content h3 {
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.slides-banner-content p {
  color: #94a3b8;
  font-size: 0.95rem;
  max-width: 600px;
}

.btn-slides {
  background-color: var(--arki-green);
  color: var(--text-inverse);
  padding: 12px 24px;
  font-weight: 700;
  border-radius: var(--radius-md);
  text-decoration: none;
  transition: opacity 0.2s;
}

.btn-slides:hover {
  opacity: 0.9;
}

/* ==========================================================================
   Codelab Viewer Layout (labs/index.html)
   ========================================================================== */

.codelab-layout {
  display: flex;
  min-height: calc(100vh - 65px);
  position: relative;
}

.codelab-sidebar {
  width: 300px;
  background-color: var(--bg-surface);
  border-right: 1px solid var(--border-subtle);
  padding: 24px 16px;
  flex-shrink: 0;
  position: sticky;
  top: 65px;
  height: calc(100vh - 65px);
  overflow-y: auto;
  transition: width 0.25s cubic-bezier(0.4, 0, 0.2, 1), padding 0.25s, opacity 0.25s;
}

.codelab-sidebar.collapsed {
  width: 0;
  min-width: 0;
  padding: 0;
  border-right: none;
  overflow: hidden;
  opacity: 0;
  pointer-events: none;
}

.sidebar-header {
  display: none;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-subtle);
}

.sidebar-header-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--arki-navy);
}

.btn-sidebar-close {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: transparent;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  font-size: 1.1rem;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.15s;
}

.btn-sidebar-close:hover {
  background-color: #fee2e2;
  color: #dc2626;
  border-color: #fca5a5;
}

.sidebar-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.5);
  backdrop-filter: blur(2px);
  z-index: 1040;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease;
}

body.sidebar-open .sidebar-backdrop {
  opacity: 1;
  pointer-events: auto;
}

.fab-sidebar-toggle {
  display: none;
  position: fixed;
  top: 68px;
  left: 16px;
  z-index: 990;
  background-color: var(--arki-blue);
  color: #ffffff;
  border: 1px solid var(--border-accent);
  border-radius: 9999px;
  padding: 6px 14px;
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  box-shadow: 0 2px 8px rgba(15, 23, 42, 0.16);
  cursor: pointer;
  align-items: center;
  gap: 4px;
  transition: transform 0.15s ease, background-color 0.15s ease;
}

.fab-sidebar-toggle:hover {
  background-color: var(--arki-dark);
  transform: translateY(-1px);
}

body.sidebar-open .fab-sidebar-toggle {
  display: none !important;
}

.sidebar-title {
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--text-light);
  letter-spacing: 0.05em;
  margin-bottom: 16px;
  padding-left: 12px;
}

.nav-lab-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.nav-lab-item button {
  width: 100%;
  text-align: left;
  padding: 10px 14px;
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  background: transparent;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-main);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 12px;
  transition: all 0.15s;
}

.nav-lab-item button:hover {
  background-color: var(--bg-canvas);
  color: var(--arki-blue);
}

.nav-lab-item.active button {
  background-color: #eff6ff;
  border-color: var(--border-accent);
  color: var(--arki-blue);
  font-weight: 700;
}

.step-indicator {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background-color: var(--border-subtle);
  color: var(--text-muted);
  font-size: 0.75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.nav-lab-item.active .step-indicator {
  background-color: var(--arki-blue);
  color: var(--text-inverse);
}

.codelab-main {
  flex: 1;
  padding: 40px 48px;
  max-width: 900px;
  min-width: 0;
  background-color: var(--bg-surface);
}

/* Codelab Lab Sections */
.lab-pane {
  display: none;
}

.lab-pane.active {
  display: block;
}

.lab-header {
  border-bottom: 1px solid var(--border-subtle);
  padding-bottom: 24px;
  margin-bottom: 32px;
}

.lab-badge-row {
  display: flex;
  gap: 10px;
  margin-bottom: 12px;
}

.lab-title {
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--arki-navy);
  margin-bottom: 12px;
  line-height: 1.25;
}

.lab-objective-box {
  background-color: var(--info-bg);
  border-left: 4px solid var(--gcp-blue);
  padding: 16px 20px;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin-bottom: 32px;
}

.lab-objective-box h4 {
  color: var(--info-text);
  font-size: 0.9rem;
  font-weight: 700;
  margin-bottom: 6px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.lab-objective-box p {
  color: var(--text-main);
  font-size: 0.95rem;
  line-height: 1.5;
}

/* Prompt Card & Copy Container */
.prompt-card {
  background-color: #f8fafc;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-md);
  margin: 24px 0;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.prompt-card-header {
  background-color: #f1f5f9;
  border-bottom: 1px solid var(--border-subtle);
  padding: 10px 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}

.prompt-label {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  display: flex;
  align-items: center;
  gap: 6px;
}

.btn-copy {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  font-size: 0.8rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-strong);
  background-color: var(--bg-surface);
  color: var(--text-main);
  cursor: pointer;
  transition: all 0.2s;
}

.btn-copy:hover {
  background-color: #e2e8f0;
  border-color: #94a3b8;
}

.btn-copy.copied {
  background-color: var(--success-bg);
  color: var(--success-text);
  border-color: var(--success-border);
}

.prompt-card-body {
  padding: 18px 20px;
}

.prompt-text {
  font-size: 0.95rem;
  color: #1e293b;
  line-height: 1.6;
  white-space: pre-wrap;
  word-break: break-word;
  overflow-wrap: anywhere;
  font-family: inherit;
}

/* Explainable Agentic & MCP Callout */
.agentic-explain-box {
  background-color: #f8fafc;
  border: 1px solid #cbd5e1;
  border-radius: var(--radius-md);
  padding: 18px 20px;
  margin: 24px 0;
}

.explain-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--arki-navy);
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.explain-content {
  font-size: 0.9rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.mcp-pill-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}

.mcp-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  background-color: #e0f2fe;
  color: #0369a1;
  border-radius: var(--radius-sm);
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 0.78rem;
  font-weight: 600;
}

/* GCP Console Checkpoint Callout */
.gcp-checkpoint-box {
  background-color: var(--warning-bg);
  border-left: 4px solid var(--gcp-yellow);
  padding: 16px 20px;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin: 24px 0;
}

.gcp-checkpoint-box h4 {
  color: var(--warning-text);
  font-size: 0.9rem;
  font-weight: 700;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.gcp-checkpoint-box p {
  color: #78350f;
  font-size: 0.9rem;
  line-height: 1.5;
}

.gcp-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  margin-top: 8px;
  color: #92400e;
  font-weight: 600;
  text-decoration: underline;
}

/* Navigation Footer */
.lab-navigation-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-top: 1px solid var(--border-subtle);
  padding-top: 32px;
  margin-top: 48px;
}

.btn-lab-nav {
  padding: 10px 20px;
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  cursor: pointer;
  border: 1px solid var(--border-strong);
  background-color: var(--bg-surface);
  color: var(--text-main);
  transition: all 0.2s;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.btn-lab-nav:hover {
  background-color: var(--bg-canvas);
  border-color: var(--arki-blue);
  color: var(--arki-blue);
}

.btn-lab-nav-primary {
  background-color: var(--arki-blue);
  color: var(--text-inverse);
  border-color: var(--arki-blue);
}

.btn-lab-nav-primary:hover {
  background-color: var(--arki-dark);
  border-color: var(--arki-dark);
  color: var(--text-inverse);
}

.lab-nav-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  flex-wrap: wrap;
  gap: 12px;
}

.btn-next {
  background-color: var(--arki-blue);
  color: var(--text-inverse);
  border-color: var(--arki-blue);
}

.btn-next:hover {
  background-color: var(--arki-dark);
  border-color: var(--arki-dark);
  color: var(--text-inverse);
}

.btn-jump-de {
  background-color: #7c3aed;
  color: var(--text-inverse);
  border-color: #7c3aed;
}

.btn-jump-de:hover {
  background-color: #6d28d9;
  border-color: #6d28d9;
  color: var(--text-inverse);
}

/* Global Footer */
.footer {
  background-color: var(--bg-surface);
  border-top: 1px solid var(--border-subtle);
  padding: 24px;
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: auto;
}

/* Semantic Lab Components & Containers */
.lab-objective {
  background-color: var(--info-bg);
  border-left: 4px solid var(--gcp-blue);
  padding: 16px 20px;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin-bottom: 32px;
}

.lab-objective h4 {
  color: var(--info-text);
  font-size: 0.9rem;
  font-weight: 700;
  margin-bottom: 6px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.lab-objective p {
  color: var(--text-main);
  font-size: 0.95rem;
  line-height: 1.5;
}

.box-info {
  background-color: #f8fafc;
  border-left: 4px solid var(--arki-blue);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 18px 20px;
  margin: 24px 0;
}

.box-info h4 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--arki-navy);
  margin-bottom: 8px;
}

.box-warning {
  background-color: var(--warning-bg);
  border-left: 4px solid var(--gcp-yellow);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 16px 20px;
  margin: 24px 0;
}

.box-warning h4 {
  color: var(--warning-text);
  font-size: 0.9rem;
  font-weight: 700;
  margin-bottom: 6px;
}

.box-tip {
  background-color: #f0fdf4;
  border-left: 4px solid #10b981;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 16px 20px;
  margin: 24px 0;
}

.box-tip h4 {
  color: #065f46;
  font-size: 0.9rem;
  font-weight: 700;
  margin-bottom: 6px;
}

.box-checkpoint {
  background-color: var(--warning-bg);
  border-left: 4px solid var(--gcp-yellow);
  padding: 16px 20px;
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  margin: 24px 0;
}

.box-checkpoint h4 {
  color: var(--warning-text);
  font-size: 0.9rem;
  font-weight: 700;
  margin-bottom: 6px;
}

.lab-step-checkbox-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 14px 18px;
  margin: 12px 0;
  transition: background-color 0.15s ease, border-color 0.15s ease;
}

.lab-step-checkbox-card:hover {
  border-color: var(--arki-blue);
  background-color: #f8fafc;
}

.step-check-label {
  display: flex;
  align-items: center;
  gap: 12px;
  cursor: pointer;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-main);
}

.step-check-input {
  width: 18px;
  height: 18px;
  cursor: pointer;
  accent-color: var(--arki-blue);
}

.cols-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin: 16px 0;
}

.cols-2:has(.screenshot-slot) {
  grid-template-columns: 1fr;
}

.cols-2 > div:has(.screenshot-slot) {
  display: none;
}

.screenshot-slot {
  display: none !important;
}

.cols-3 {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 16px;
  margin: 16px 0;
}

.cols-4 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin: 16px 0;
}

.slide-card {
  background-color: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 16px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

.mermaid {
  background-color: #f8fafc;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 20px;
  margin: 20px 0;
  display: flex;
  justify-content: center;
  align-items: center;
  overflow-x: auto;
}

.mermaid svg {
  max-width: 100%;
}

.code-snippet {
  background-color: #0f172a;
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  margin: 20px 0;
  color: #f8fafc;
}


/* ==========================================================================
   Expandable Prompt Explainer ("Me explique mais sobre esse prompt")
   Hidden by default via native <details>, expands on click
   ========================================================================== */

.prompt-explainer {
  background-color: #f8fafc;
  border: 1px solid #cbd5e1;
  border-left: 4px solid var(--arki-blue);
  border-radius: var(--radius-md);
  margin: -12px 0 28px 0;
  overflow: hidden;
  transition: all 0.2s ease;
}

.prompt-explainer[open] {
  background-color: #ffffff;
  box-shadow: var(--shadow-sm);
}

.prompt-explainer summary {
  padding: 12px 18px;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--arki-dark);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
  background-color: #eff6ff;
  transition: background-color 0.15s ease;
}

.prompt-explainer summary::-webkit-details-marker {
  display: none;
}

.prompt-explainer summary:hover {
  background-color: #dbeafe;
}

.explainer-summary-left {
  display: flex;
  align-items: center;
  gap: 8px;
}

.explainer-chevron {
  font-size: 0.8rem;
  color: var(--arki-blue);
  transition: transform 0.2s ease;
}

.prompt-explainer[open] .explainer-chevron {
  transform: rotate(180deg);
}

.explainer-body {
  padding: 18px 22px;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.92rem;
  color: var(--text-main);
}

.explainer-body p {
  margin-bottom: 12px;
  line-height: 1.6;
}

.explainer-body ul {
  margin: 10px 0 12px 20px;
}

.explainer-body li {
  margin-bottom: 8px;
  line-height: 1.55;
}

.explainer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 12px;
  margin-top: 12px;
}

.explainer-item {
  background-color: #f8fafc;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
}

.explainer-item strong {
  display: block;
  color: var(--arki-navy);
  font-size: 0.85rem;
  margin-bottom: 4px;
}

.explainer-item span {
  font-size: 0.83rem;
  color: var(--text-muted);
  line-height: 1.45;
  display: block;
}

/* ==========================================================================
   Visual Architecture Diagrams & Technical Deep-Dive Blocks
   ========================================================================== */

.arch-diagram-box {
  background: linear-gradient(180deg, #f8fafc 0%, #f1f5f9 100%);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin: 28px 0;
}

.arch-diagram-title {
  font-size: 0.85rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--arki-dark);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.arch-flow {
  display: flex;
  align-items: stretch;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}

.arch-node {
  flex: 1;
  min-width: 160px;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-top: 3px solid var(--arki-blue);
  border-radius: var(--radius-md);
  padding: 14px;
  box-shadow: var(--shadow-sm);
}

.arch-node-green {
  border-top-color: var(--gcp-green);
}

.arch-node-yellow {
  border-top-color: var(--gcp-yellow);
}

.arch-node-purple {
  border-top-color: #7c3aed;
}

.arch-node-tag {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  padding: 2px 6px;
  border-radius: 4px;
  background-color: #eff6ff;
  color: var(--arki-blue);
  margin-bottom: 6px;
}

.arch-node h5 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--arki-navy);
  margin-bottom: 6px;
}

.arch-node p {
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.45;
  margin: 0;
}

.arch-pillars-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 14px;
  margin-top: 14px;
}

.arch-pillar-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 16px;
  box-shadow: var(--shadow-sm);
}

.arch-pillar-card h5 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--arki-dark);
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.arch-pillar-card p {
  font-size: 0.84rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin: 0;
}

/* Technical Comparison Tables inside Labs */
.tech-table-wrapper {
  overflow-x: auto;
  margin: 20px 0 28px 0;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
}

.tech-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  text-align: left;
  background-color: var(--bg-surface);
}

.tech-table th {
  background-color: #f1f5f9;
  color: var(--arki-navy);
  font-weight: 700;
  padding: 12px 16px;
  border-bottom: 2px solid var(--border-strong);
}

.tech-table td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-main);
  vertical-align: top;
}

.tech-table tr:last-child td {
  border-bottom: none;
}

/* Quota & Model Selection Callout Box */
.quota-tip-box {
  background-color: #ecfdf5;
  border: 1px solid #a7f3d0;
  border-left: 4px solid var(--gcp-green);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  padding: 16px 20px;
  margin: 24px 0;
}

.quota-tip-box h4 {
  color: #065f46;
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.quota-tip-box p {
  color: #064e3b;
  font-size: 0.9rem;
  line-height: 1.55;
  margin: 0;
}

/* ==========================================================================
   Tracks Organization (Business & Analytics vs Data Engineering & AI + Catalog)
   ========================================================================== */

.track-banner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-left: 6px solid var(--arki-blue);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  margin: 40px 0 24px 0;
  box-shadow: var(--shadow-sm);
}

.track-banner-setup {
  border-left-color: #0284c7;
}

.track-banner-de {
  border-left-color: #7c3aed;
}

.track-banner-buffer,
.track-banner-catalog {
  border-left-color: var(--arki-green);
}

.track-banner-info h2 {
  font-size: 1.45rem;
  font-weight: 800;
  color: var(--arki-navy);
  margin-bottom: 4px;
}

.track-banner-info p {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin: 0;
}

.track-pill {
  padding: 6px 14px;
  border-radius: 9999px;
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  background-color: #dbeafe;
  color: var(--arki-dark);
}

.track-pill-setup {
  background-color: #e0f2fe;
  color: #0369a1;
}

.track-pill-de {
  background-color: #ede9fe;
  color: #5b21b6;
}

.track-pill-buffer,
.track-pill-catalog {
  background-color: #dcfce7;
  color: #166534;
}

.badge-de-kc { background-color: #e0e7ff; color: #3730a3; }
.badge-de-graph { background-color: #fae8ff; color: #86198f; }
.badge-de-ai { background-color: #fef3c7; color: #92400e; }
.badge-de-dataform { background-color: #ccfbf1; color: #115e59; }
.badge-buffer,
.badge-catalog { background-color: #dcfce7; color: #166534; }

.sidebar-group-label {
  font-size: 0.72rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--arki-blue);
  margin: 20px 0 8px 12px;
  padding-top: 12px;
  border-top: 1px solid var(--border-subtle);
}

.sidebar-group-label:first-of-type {
  margin-top: 4px;
  padding-top: 0;
  border-top: none;
}

.sidebar-group-setup {
  color: #0284c7;
}

.sidebar-group-de {
  color: #6d28d9;
}

.sidebar-group-buffer,
.sidebar-group-catalog {
  color: #15803d;
}

/* Catalog & Industry Scenarios Grid */
.buffer-scenarios-grid,
.catalog-scenarios-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
  margin-bottom: 48px;
}

.scenario-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-top: 4px solid var(--arki-green);
  border-radius: var(--radius-lg);
  padding: 26px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
}

.scenario-card h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--arki-navy);
  margin-bottom: 10px;
}

.scenario-card p {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 16px;
  flex-grow: 1;
}

.scenario-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 18px;
}

/* ==========================================================================
   Instructor Guide Layout (/instructor/index.html)
   ========================================================================== */

.instructor-main {
  max-width: 1120px;
  margin: 0 auto;
  padding: 40px 24px;
}

.instructor-section {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 32px;
  margin-bottom: 32px;
  box-shadow: var(--shadow-sm);
}

.instructor-section h2 {
  font-size: 1.55rem;
  font-weight: 800;
  color: var(--arki-navy);
  margin-bottom: 14px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--border-subtle);
}

.instructor-section h3 {
  font-size: 1.18rem;
  font-weight: 700;
  color: var(--arki-dark);
  margin: 24px 0 10px 0;
}

.demo-playbook-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(460px, 1fr));
  gap: 20px;
  margin-top: 20px;
}

.demo-card {
  background-color: #f8fafc;
  border: 1px solid var(--border-strong);
  border-left: 5px solid var(--gcp-blue);
  border-radius: var(--radius-md);
  padding: 20px 24px;
}

.demo-card h4 {
  font-size: 1.08rem;
  font-weight: 700;
  color: var(--arki-navy);
  margin-bottom: 10px;
}

.demo-card ol, .demo-card ul {
  margin-left: 20px;
  font-size: 0.9rem;
  color: var(--text-main);
}

.demo-card li {
  margin-bottom: 8px;
  line-height: 1.5;
}

/* Lab Typography Spacing inside Codelab */
.lab-pane h3 {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--arki-navy);
  margin: 32px 0 12px 0;
}

.lab-pane h4 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--arki-dark);
  margin: 20px 0 8px 0;
}

.lab-pane p {
  margin-bottom: 14px;
  color: var(--text-main);
}

.lab-pane ul, .lab-pane ol {
  margin: 12px 0 20px 24px;
}

.lab-pane li {
  margin-bottom: 8px;
}

.code-block-dark {
  background-color: var(--bg-code);
  color: #f8fafc;
  padding: 16px 20px;
  border-radius: var(--radius-md);
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 0.85rem;
  overflow-x: auto;
  margin: 16px 0 24px 0;
  line-height: 1.55;
  max-width: 100%;
}

/* Global Responsive Guards */
pre, code {
  max-width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

table {
  max-width: 100%;
}

/* ==========================================================================
   Responsive & Split-Screen (50% Width) Optimizations
   ========================================================================== */

@keyframes slideDownMenu {
  from {
    opacity: 0;
    transform: translateY(-8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 1024px) {
  /* Header in split screen or tablet */
  .header-container {
    padding: 10px 16px;
  }

  .brand-group {
    gap: 8px;
  }

  .brand-logo-arki1 {
    height: 26px;
  }

  .brand-logo-gcp {
    height: 20px;
  }

  .brand-divider {
    height: 18px;
  }

  .brand-title {
    font-size: 0.98rem;
  }

  /* Hamburger menu appears on narrow split-screen */
  .btn-menu-toggle {
    display: flex;
  }

  /* Dropdown actions menu */
  .header-actions {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--bg-surface);
    border-bottom: 2px solid var(--border-subtle);
    box-shadow: var(--shadow-lg);
    padding: 16px 20px;
    flex-direction: column;
    gap: 10px;
    z-index: 1000;
  }

  .header-actions.open {
    display: flex;
    animation: slideDownMenu 0.2s ease-out;
  }

  .header-actions .lang-select {
    width: 100%;
    padding: 10px 14px;
    font-size: 0.92rem;
  }

  .header-actions .btn-nav {
    width: 100%;
    padding: 10px 16px;
    font-size: 0.92rem;
    text-align: center;
  }

  /* Codelab Sidebar becomes an off-canvas drawer */
  .codelab-layout {
    flex-direction: column;
  }

  .codelab-sidebar {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    height: 100vh;
    width: 310px;
    max-width: 86vw;
    z-index: 1050;
    transform: translateX(-100%);
    box-shadow: var(--shadow-lg);
    border-right: 1px solid var(--border-strong);
    background-color: var(--bg-surface);
    padding: 20px 16px;
  }

  body.sidebar-open .codelab-sidebar {
    transform: translateX(0);
  }

  .sidebar-header {
    display: flex;
  }

  .fab-sidebar-toggle {
    display: inline-flex;
  }

  /* Main content expands to full split screen */
  .codelab-main {
    max-width: 100%;
    padding: 44px 20px 24px 20px;
    min-width: 0;
  }

  /* Hub improvements */
  .main-content {
    padding: 28px 16px;
  }

  .hero-section {
    padding: 40px 16px;
  }

  .hero-title {
    font-size: 2rem;
  }

  .starter-download-card {
    margin: 16px auto 32px auto;
    padding: 24px 18px;
  }

  .quickstart-steps {
    grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
    gap: 12px;
  }

  .labs-grid {
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 16px;
  }

  .demo-playbook-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .brand-divider,
  .brand-logo-gcp {
    display: none;
  }

  .brand-title {
    font-size: 0.92rem;
  }

  .codelab-main {
    padding: 16px 12px;
  }

  .hero-title {
    font-size: 1.6rem;
  }

  .hero-subtitle {
    font-size: 0.95rem;
  }

  .btn-download-primary {
    width: 100%;
    justify-content: center;
  }

  .prompt-card-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
  }

  .btn-copy {
    width: 100%;
    justify-content: center;
  }

  .lab-navigation-bar {
    flex-direction: column;
    gap: 12px;
    align-items: stretch;
  }

  .btn-lab-nav {
    width: 100%;
    justify-content: center;
  }
}

/* ==========================================================================
   Event Gatekeeper: Passcode Protection Screen
   ========================================================================== */

.gate-wrapper {
  min-height: calc(100vh - 70px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 20px;
}

.gate-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  max-width: 480px;
  width: 100%;
  padding: 36px 32px;
  text-align: center;
}

.gate-icon-container {
  width: 56px;
  height: 56px;
  margin: 0 auto 18px;
  background-color: var(--info-bg);
  border: 1px solid var(--border-accent);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--arki-blue);
}

.gate-badge {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--arki-blue);
  background-color: var(--info-bg);
  border: 1px solid var(--border-accent);
  padding: 4px 12px;
  border-radius: 9999px;
  margin-bottom: 16px;
}

.gate-title {
  font-size: 1.45rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 10px;
}

.gate-subtitle {
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 24px;
}

.gate-alert {
  display: flex;
  align-items: center;
  gap: 10px;
  background-color: #fef2f2;
  border: 1px solid #fecaca;
  color: #991b1b;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  font-size: 0.88rem;
  margin-bottom: 20px;
  text-align: left;
}

.gate-alert-icon {
  flex-shrink: 0;
  font-size: 1.1rem;
}

.gate-form {
  display: flex;
  flex-direction: column;
  gap: 18px;
  text-align: left;
}

.gate-field-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 6px;
}

.gate-input {
  width: 100%;
  padding: 12px 14px;
  font-size: 1rem;
  font-family: inherit;
  color: var(--text-main);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-sm);
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
  letter-spacing: 0.05em;
}

.gate-input:focus {
  outline: none;
  border-color: var(--arki-blue);
  box-shadow: 0 0 0 3px rgba(54, 101, 173, 0.18);
}

.gate-btn-submit {
  width: 100%;
  padding: 12px 18px;
  font-size: 0.96rem;
  font-weight: 600;
  color: var(--text-inverse);
  background-color: var(--arki-blue);
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: background-color 0.15s ease, transform 0.05s ease;
}

.gate-btn-submit:hover {
  background-color: var(--arki-dark);
}

.gate-btn-submit:active {
  transform: translateY(1px);
}

.gate-footer-note {
  margin-top: 24px;
  font-size: 0.8rem;
  color: var(--text-light);
  line-height: 1.4;
  text-align: center;
}