/* ========================================================
   NETWORK // VIBEOPS - High-Tech Cyber Dark Design System
   ======================================================== */

:root {
  --bg-core: #060911;
  --bg-surface: rgba(15, 23, 42, 0.72);
  --bg-card: rgba(18, 28, 51, 0.65);
  --bg-card-hover: rgba(24, 38, 70, 0.85);

  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-glow: rgba(34, 211, 238, 0.35);

  --accent-cyan: #22d3ee;
  --accent-cyan-glow: rgba(34, 211, 238, 0.4);
  --accent-emerald: #10b981;
  --accent-amber: #f59e0b;
  --accent-purple: #c084fc;
  --accent-rose: #f43f5e;
  --accent-orange: #fb923c;

  --text-main: #f8fafc;
  --text-sub: #94a3b8;
  --text-muted: #64748b;

  --font-sans: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
}

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

html {
  scroll-padding-top: 100px;
  background-color: var(--bg-core);
  color: var(--text-main);
  font-family: var(--font-sans);
}

body {
  min-height: 100vh;
  position: relative;
  overflow-x: clip;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

/* Ambient glow blobs */
.ambient-glow {
  position: fixed;
  width: 50vw;
  height: 50vw;
  max-width: 600px;
  max-height: 600px;
  border-radius: 50%;
  pointer-events: none;
  filter: blur(140px);
  z-index: 0;
  opacity: 0.16;
}

.glow-cyan {
  top: -100px;
  left: -100px;
  background: var(--accent-cyan);
}

.glow-emerald {
  bottom: 20%;
  right: -100px;
  background: var(--accent-emerald);
}

.glow-purple {
  top: 50%;
  left: 20%;
  background: var(--accent-purple);
  opacity: 0.1;
}

/* Reading Progress Bar */
.reading-progress-track {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: rgba(255, 255, 255, 0.05);
  z-index: 1000;
}

.reading-progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent-cyan), var(--accent-emerald));
  box-shadow: 0 0 10px var(--accent-cyan);
  transition: width 0.1s ease-out;
}

/* Layout Container */
.layout-container {
  position: relative;
  z-index: 1;
  max-width: 1120px;
  margin: 0 auto;
  padding: 24px 20px 80px;
}

/* Global Top Header */
.hub-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 24px;
  background: var(--bg-surface);
  backdrop-filter: blur(16px);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  margin-bottom: 40px;
}

.header-left {
  display: flex;
  align-items: center;
  gap: 16px;
  min-width: 0;
}

.btn-back {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--border-subtle);
  color: var(--accent-cyan);
  text-decoration: none;
  font-size: 0.85rem;
  font-weight: 600;
  font-family: var(--font-mono);
  transition: all 0.2s ease;
  white-space: nowrap;
  flex-shrink: 0;
}

.btn-back:hover {
  background: rgba(34, 211, 238, 0.15);
  border-color: var(--accent-cyan);
  transform: translateX(-2px);
}

.brand-divider {
  color: var(--text-muted);
  font-family: var(--font-mono);
  flex-shrink: 0;
}

.brand-text {
  min-width: 0;
}

.brand-title {
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: 1.15rem;
  letter-spacing: -0.5px;
  white-space: nowrap;
}

.accent-dot {
  color: var(--accent-cyan);
}

.brand-sub {
  display: block;
  font-size: 0.68rem;
  color: var(--text-sub);
  font-family: var(--font-mono);
  letter-spacing: 1.5px;
  white-space: nowrap;
}

.header-status {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.status-indicator {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.3);
  border-radius: 9999px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: #34d399;
  white-space: nowrap;
}

.pulse-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #10b981;
  box-shadow: 0 0 10px #10b981;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% { transform: scale(0.95); opacity: 0.7; }
  50% { transform: scale(1.3); opacity: 1; }
  100% { transform: scale(0.95); opacity: 0.7; }
}

/* Hero Section */
.hero-section {
  text-align: center;
  padding: 20px 0 50px;
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 18px;
  border-radius: 9999px;
  background: rgba(34, 211, 238, 0.1);
  border: 1px solid rgba(34, 211, 238, 0.3);
  color: var(--accent-cyan);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 1.5px;
  margin-bottom: 24px;
}

.hero-title {
  font-size: clamp(2rem, 4.5vw, 3.2rem);
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 20px;
  letter-spacing: -1px;
}

.gradient-text {
  background: linear-gradient(135deg, #22d3ee 0%, #38bdf8 40%, #a855f7 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-desc {
  max-width: 760px;
  margin: 0 auto 36px;
  font-size: 1.05rem;
  color: var(--text-sub);
  word-break: keep-all;
}

/* Hero Metrics Grid */
.hero-metrics {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  max-width: 840px;
  margin: 0 auto;
}

.metric-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  text-align: center;
  backdrop-filter: blur(10px);
}

.metric-val {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--accent-cyan);
  line-height: 1.2;
}

.metric-label {
  display: block;
  font-size: 0.82rem;
  color: var(--text-sub);
  margin-top: 4px;
}

/* Sticky Pipeline Navigation Bar */
.pipeline-nav {
  position: sticky;
  top: 14px;
  z-index: 100;
  margin: 30px 0 50px;
  background: rgba(6, 9, 17, 0.85);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 10px 16px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

.pipeline-nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  overflow-x: auto;
  gap: 8px;
  scrollbar-width: none;
}

.pipeline-nav-inner::-webkit-scrollbar {
  display: none;
}

.nav-step {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  text-decoration: none;
  color: var(--text-sub);
  font-size: 0.85rem;
  white-space: nowrap;
  transition: all 0.2s ease;
}

.nav-step .step-num {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  opacity: 0.7;
}

.nav-step:hover {
  color: var(--text-main);
  background: rgba(255, 255, 255, 0.05);
}

.nav-step.active {
  color: var(--accent-cyan);
  background: rgba(34, 211, 238, 0.12);
  border: 1px solid rgba(34, 211, 238, 0.3);
  font-weight: 700;
}

.pipeline-arrow {
  color: var(--text-muted);
  font-size: 0.75rem;
  opacity: 0.5;
}

/* Chapter Card Styles */
.chapter-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 36px 32px;
  margin-bottom: 50px;
  backdrop-filter: blur(12px);
  transition: border-color 0.25s ease;
}

.chapter-card:hover {
  border-color: rgba(34, 211, 238, 0.25);
}

.chapter-header {
  border-bottom: 1px solid var(--border-subtle);
  padding-bottom: 24px;
  margin-bottom: 28px;
}

.chapter-badge-wrap {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
}

.badge-ch {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 800;
  padding: 4px 10px;
  background: rgba(34, 211, 238, 0.15);
  border: 1px solid rgba(34, 211, 238, 0.4);
  color: var(--accent-cyan);
  border-radius: 6px;
  letter-spacing: 1px;
}

.badge-legal {
  background: rgba(168, 85, 247, 0.15);
  border-color: rgba(168, 85, 247, 0.4);
  color: var(--accent-purple);
}

.legal-card {
  border-color: rgba(168, 85, 247, 0.3);
  background: linear-gradient(180deg, rgba(168, 85, 247, 0.05), rgba(18, 28, 51, 0.65));
}

.legal-card:hover {
  border-color: rgba(168, 85, 247, 0.5);
}

.legal-box-highlight {
  background: linear-gradient(145deg, rgba(168, 85, 247, 0.08), rgba(6, 182, 212, 0.03));
  border-color: rgba(168, 85, 247, 0.35);
}

.badge-seo {
  background: rgba(56, 189, 248, 0.15);
  border-color: rgba(56, 189, 248, 0.4);
  color: #38bdf8;
}

.seo-card {
  border-color: rgba(56, 189, 248, 0.3);
  background: linear-gradient(180deg, rgba(56, 189, 248, 0.05), rgba(18, 28, 51, 0.65));
}

.seo-card:hover {
  border-color: rgba(56, 189, 248, 0.55);
}

.badge-tag {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.chapter-title {
  font-size: 1.6rem;
  font-weight: 700;
  letter-spacing: -0.5px;
  margin-bottom: 12px;
  color: var(--text-main);
}

.chapter-summary {
  font-size: 1rem;
  color: var(--text-sub);
  line-height: 1.6;
}

/* Concept & Box Styles */
.concept-box {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px;
  margin-bottom: 24px;
}

.fail2ban-box {
  background: linear-gradient(145deg, rgba(16, 185, 129, 0.07), rgba(6, 182, 212, 0.03));
  border-color: rgba(16, 185, 129, 0.35);
}

.fail2ban-box .box-title {
  color: #34d399;
}

.box-title {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 16px;
  color: #e2e8f0;
}

.bullet-list {
  padding-left: 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  color: #cbd5e1;
}

.bullet-list li strong {
  color: #f1f5f9;
}

/* Fact Highlight Box (Cloudflare Chapter) */
.fact-highlight-box {
  background: linear-gradient(145deg, rgba(251, 146, 60, 0.08), rgba(245, 158, 11, 0.04));
  border: 1px solid rgba(251, 146, 60, 0.35);
  border-radius: var(--radius-md);
  padding: 26px;
  margin-bottom: 28px;
}

.fact-title {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--accent-orange);
  margin-bottom: 18px;
}

.fact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-bottom: 20px;
}

.fact-item {
  background: rgba(0, 0, 0, 0.25);
  padding: 16px;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(251, 146, 60, 0.15);
}

.f-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--accent-orange);
  margin-bottom: 6px;
}

.f-txt {
  font-size: 0.85rem;
  color: #cbd5e1;
  line-height: 1.5;
}

.fact-quote {
  font-size: 0.95rem;
  color: #fed7aa;
  background: rgba(0, 0, 0, 0.35);
  padding: 14px 20px;
  border-left: 4px solid var(--accent-orange);
  border-radius: 4px;
  font-style: italic;
}

/* Tables */
.table-responsive {
  overflow-x: auto;
}

.styled-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
  margin-top: 8px;
}

.styled-table th,
.styled-table td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: 1px solid var(--border-subtle);
}

.styled-table th {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-sub);
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 0.8rem;
  letter-spacing: 0.5px;
}

.styled-table td code {
  background: rgba(34, 211, 238, 0.1);
  color: var(--accent-cyan);
  padding: 2px 6px;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
}

/* Cloudflare Compare & Loops */
.cloud-compare {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 20px;
}

.cloud-card {
  padding: 18px;
  border-radius: var(--radius-sm);
  background: rgba(0, 0, 0, 0.25);
  border: 1px solid var(--border-subtle);
  font-size: 0.88rem;
  line-height: 1.55;
}

.cloud-card.orange {
  border-color: rgba(251, 146, 60, 0.4);
}

.c-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 8px;
  border-radius: 4px;
  margin-bottom: 10px;
}

.orange-badge {
  background: rgba(251, 146, 60, 0.2);
  color: var(--accent-orange);
}

.grey-badge {
  background: rgba(148, 163, 184, 0.2);
  color: var(--text-sub);
}

.redirect-trap-box {
  background: rgba(244, 63, 94, 0.07);
  border: 1px solid rgba(244, 63, 94, 0.3);
  border-radius: var(--radius-sm);
  padding: 18px 20px;
  font-size: 0.9rem;
}

.trap-head {
  display: flex;
  align-items: center;
  gap: 8px;
  color: #fda4af;
  margin-bottom: 10px;
}

.loop-diagram {
  background: rgba(0, 0, 0, 0.45);
  padding: 12px;
  border-radius: 6px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: #fecdd3;
  margin: 12px 0;
  word-break: break-all;
}

.trap-solution {
  color: #6ee7b7;
}

/* Analogy Grid (Server & Ports) */
.analogy-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.analogy-item {
  background: rgba(0, 0, 0, 0.25);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 18px;
}

.a-icon {
  font-size: 1.5rem;
  margin-bottom: 8px;
  display: block;
}

.analogy-item h4 {
  font-size: 1rem;
  color: var(--text-main);
  margin-bottom: 8px;
}

.analogy-item p {
  font-size: 0.85rem;
  color: var(--text-sub);
  line-height: 1.5;
}

/* Code Flow Card */
.code-flow-card {
  background: rgba(0, 0, 0, 0.35);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 18px;
  margin-top: 14px;
  font-family: var(--font-mono);
  font-size: 0.85rem;
}

.flow-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 6px 0;
}

.flow-badge {
  background: rgba(255, 255, 255, 0.08);
  padding: 3px 8px;
  border-radius: 4px;
  font-size: 0.75rem;
  color: var(--accent-cyan);
}

.flow-arrow {
  padding: 4px 20px;
  color: var(--text-muted);
  font-size: 0.8rem;
}

/* SSL Cards */
.ssl-choice-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.ssl-card {
  position: relative;
  background: rgba(0, 0, 0, 0.3);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px 22px;
  display: flex;
  flex-direction: column;
  transition: all 0.25s ease;
}

.ssl-card-recommended {
  background: linear-gradient(145deg, rgba(16, 185, 129, 0.08), rgba(6, 182, 212, 0.05));
  border: 1px solid rgba(16, 185, 129, 0.45);
  box-shadow: 0 8px 24px rgba(16, 185, 129, 0.12), 0 0 16px rgba(0, 242, 254, 0.08);
}

.ssl-card-recommended:hover {
  border-color: #10b981;
  box-shadow: 0 12px 30px rgba(16, 185, 129, 0.2);
}

.ssl-card-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 800;
  color: #34d399;
  background: rgba(16, 185, 129, 0.15);
  border: 1px solid rgba(16, 185, 129, 0.35);
  border-radius: 4px;
  padding: 3px 8px;
  letter-spacing: 0.5px;
  margin-bottom: 12px;
  align-self: flex-start;
}

.ssl-card-alt {
  background: rgba(15, 23, 42, 0.45);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.ssl-card-alt:hover {
  border-color: rgba(255, 255, 255, 0.25);
}

.ssl-card-badge-sub {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 800;
  color: #94a3b8;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 4px;
  padding: 3px 8px;
  letter-spacing: 0.5px;
  margin-bottom: 12px;
  align-self: flex-start;
}

.ssl-card h4 {
  font-size: 1.05rem;
  font-weight: 800;
  color: #ffffff;
  margin: 0 0 10px 0;
  line-height: 1.4;
}

.ssl-card-recommended h4 {
  color: #a7f3d0;
}

.ssl-card p {
  font-size: 0.88rem;
  color: var(--text-sub);
  line-height: 1.6;
  margin: 0 0 12px 0;
}

.ssl-card-tip {
  background: rgba(0, 242, 254, 0.06);
  border-left: 3px solid #00f2fe;
  padding: 10px 12px;
  border-radius: 4px;
  font-size: 0.82rem;
  color: #e2e8f0;
  margin-top: auto;
  line-height: 1.55;
}

.ssl-card-subtext {
  font-size: 0.82rem;
  color: var(--text-muted);
  line-height: 1.55;
  margin-top: auto;
  padding-top: 8px;
  border-top: 1px dashed rgba(255, 255, 255, 0.08);
}

/* Error Code Grid */
.error-code-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.error-item {
  background: rgba(0, 0, 0, 0.25);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 18px;
}

.err-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 700;
  padding: 4px 8px;
  border-radius: 4px;
  margin-bottom: 10px;
}

.e-502 { background: rgba(239, 68, 68, 0.2); color: #f87171; }
.e-521 { background: rgba(245, 158, 11, 0.2); color: #fbbf24; }
.e-403 { background: rgba(168, 85, 247, 0.2); color: #c084fc; }
.e-loop { background: rgba(59, 130, 246, 0.2); color: #60a5fa; }

.error-item p {
  font-size: 0.88rem;
  color: #e2e8f0;
  margin-bottom: 8px;
}

.error-item small {
  font-family: var(--font-mono);
  color: var(--text-muted);
  font-size: 0.8rem;
}

/* AI Prompt Recipe Box */
.prompt-box {
  background: rgba(16, 185, 129, 0.05);
  border: 1px solid rgba(16, 185, 129, 0.25);
  border-radius: var(--radius-md);
  padding: 20px;
  margin: 24px 0;
}

.prompt-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.prompt-tag {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 700;
  color: #34d399;
}

.btn-copy {
  background: rgba(16, 185, 129, 0.15);
  border: 1px solid rgba(16, 185, 129, 0.4);
  color: #34d399;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 6px 14px;
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-copy:hover {
  background: #10b981;
  color: #060911;
  box-shadow: 0 0 12px rgba(16, 185, 129, 0.5);
}

.prompt-code {
  background: #04060a;
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius-sm);
  padding: 16px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: #e2e8f0;
  white-space: pre-wrap;
  word-break: break-all;
  line-height: 1.6;
}

/* Security Box (Red/Orange Alert) */
.security-box {
  background: rgba(244, 63, 94, 0.06);
  border: 1px solid rgba(244, 63, 94, 0.3);
  border-radius: var(--radius-md);
  padding: 22px;
  margin-top: 24px;
}

.sec-head {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
}

.sec-icon {
  font-size: 1.3rem;
}

.sec-head h4 {
  font-size: 1.05rem;
  font-weight: 700;
  color: #fb7185;
}

.sec-content {
  font-size: 0.92rem;
  color: #cbd5e1;
  line-height: 1.65;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.sec-content strong {
  color: #fff;
}

.code-snippet-highlight {
  background: #020408;
  border-left: 3px solid #f43f5e;
  padding: 12px 16px;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: #fda4af;
  margin-top: 6px;
  white-space: pre;
  overflow-x: auto;
}

.cmd-box {
  background: #020408;
  border: 1px solid var(--border-subtle);
  padding: 10px 14px;
  border-radius: 6px;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--accent-cyan);
  margin-top: 8px;
}

/* ==============================================
   Audit Checklist Section (Interactive Tool)
   ============================================== */
.audit-section {
  margin-top: 60px;
}

.audit-card {
  background: linear-gradient(180deg, rgba(34, 211, 238, 0.05), rgba(15, 23, 42, 0.8));
  border: 1px solid rgba(34, 211, 238, 0.3);
  border-radius: var(--radius-lg);
  padding: 40px 32px;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.4);
}

.audit-head {
  text-align: center;
  margin-bottom: 32px;
}

.audit-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--accent-cyan);
  background: rgba(34, 211, 238, 0.15);
  border: 1px solid rgba(34, 211, 238, 0.4);
  padding: 4px 12px;
  border-radius: 9999px;
  margin-bottom: 12px;
}

.audit-title {
  font-size: 1.8rem;
  font-weight: 800;
  margin-bottom: 10px;
}

.audit-desc {
  color: var(--text-sub);
  font-size: 0.95rem;
}

.audit-checklist {
  display: flex;
  flex-direction: column;
  gap: 14px;
  max-width: 800px;
  margin: 0 auto 32px;
}

.check-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  padding: 16px 20px;
  background: rgba(0, 0, 0, 0.3);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all 0.2s ease;
}

.check-item:hover {
  background: rgba(255, 255, 255, 0.03);
  border-color: rgba(34, 211, 238, 0.3);
}

.audit-cb {
  appearance: none;
  width: 22px;
  height: 22px;
  border: 2px solid var(--text-muted);
  border-radius: 6px;
  margin-top: 2px;
  flex-shrink: 0;
  cursor: pointer;
  transition: all 0.2s ease;
  position: relative;
}

.audit-cb:checked {
  background: var(--accent-cyan);
  border-color: var(--accent-cyan);
}

.audit-cb:checked::after {
  content: '✓';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -55%);
  color: #060911;
  font-size: 14px;
  font-weight: 900;
}

.check-body {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.check-label {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-main);
}

.check-sub {
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* Result Gauge */
.audit-result-box {
  max-width: 800px;
  margin: 0 auto;
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px;
}

.gauge-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 12px;
}

.score-display {
  font-family: var(--font-mono);
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--accent-cyan);
}

.gauge-bar-bg {
  width: 100%;
  height: 12px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 9999px;
  overflow: hidden;
  margin-bottom: 16px;
}

.gauge-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, #f43f5e 0%, #f59e0b 50%, #10b981 100%);
  border-radius: 9999px;
  transition: width 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.audit-feedback {
  text-align: center;
  font-size: 0.9rem;
  color: var(--text-sub);
}

/* Footer */
.hub-footer {
  margin-top: 80px;
  border-top: 1px solid var(--border-subtle);
  padding-top: 36px;
}

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

.footer-brand {
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: 1.1rem;
}

.footer-desc {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.footer-links {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.footer-links a {
  color: var(--text-sub);
  text-decoration: none;
  font-size: 0.85rem;
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: var(--accent-cyan);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  font-size: 0.78rem;
  color: var(--text-muted);
  flex-wrap: wrap;
}

/* Toast Popup */
.toast-popup {
  position: fixed;
  bottom: 84px;
  right: 24px;
  background: #10b981;
  color: #060911;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.85rem;
  padding: 12px 20px;
  border-radius: var(--radius-sm);
  box-shadow: 0 10px 25px rgba(16, 185, 129, 0.4);
  z-index: 9999;
  transform: translateY(100px);
  opacity: 0;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  pointer-events: none;
}

.toast-popup.show {
  transform: translateY(0);
  opacity: 1;
}

/* ==============================================
   Operator Disclaimer Banner
   ============================================== */
.disclaimer-banner {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  background: linear-gradient(135deg, rgba(245, 158, 11, 0.08), rgba(15, 23, 42, 0.7));
  border: 1px solid rgba(245, 158, 11, 0.35);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  max-width: 840px;
  margin: 28px auto 0;
  text-align: left;
  backdrop-filter: blur(12px);
}

.disc-icon {
  font-size: 1.5rem;
  line-height: 1;
  flex-shrink: 0;
  margin-top: 2px;
}

.disc-text {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.disc-tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--accent-amber);
  letter-spacing: 1px;
}

.disc-text p {
  font-size: 0.88rem;
  color: #cbd5e1;
  line-height: 1.6;
}

/* ==============================================
   Operator Pick Box
   ============================================== */
.operator-pick-box {
  background: linear-gradient(135deg, rgba(16, 185, 129, 0.08), rgba(6, 182, 212, 0.04));
  border: 1px solid rgba(16, 185, 129, 0.3);
  border-radius: var(--radius-md);
  padding: 20px 22px;
  margin: 20px 0 24px;
}

.op-badge {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 800;
  color: #34d399;
  letter-spacing: 0.5px;
  margin-bottom: 8px;
}

.op-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: #f1f5f9;
  margin-bottom: 8px;
}

.op-desc {
  font-size: 0.88rem;
  color: #cbd5e1;
  line-height: 1.6;
}

/* ==============================================
   Routing Dilemma & Details Accordion
   ============================================== */
.routing-dilemma-box {
  border-color: rgba(56, 189, 248, 0.35);
  background: linear-gradient(145deg, rgba(56, 189, 248, 0.05), rgba(15, 23, 42, 0.5));
}

.dilemma-highlight {
  background: rgba(0, 0, 0, 0.35);
  border-left: 3px solid var(--accent-cyan);
  padding: 14px 18px;
  border-radius: 4px;
  font-size: 0.9rem;
  color: #e2e8f0;
  margin: 16px 0;
  line-height: 1.6;
}

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

.choice-card {
  padding: 18px;
  border-radius: var(--radius-sm);
  background: rgba(0, 0, 0, 0.3);
  border: 1px solid var(--border-subtle);
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.choice-grey {
  border-color: rgba(148, 163, 184, 0.4);
}

.choice-orange {
  border-color: rgba(251, 146, 60, 0.4);
}

.choice-tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--accent-cyan);
}

.choice-orange .choice-tag {
  color: var(--accent-orange);
}

.choice-card h5 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-main);
}

.choice-card p {
  font-size: 0.84rem;
  color: var(--text-sub);
  line-height: 1.55;
}

.trace-tip-box {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  background: rgba(34, 211, 238, 0.08);
  border: 1px solid rgba(34, 211, 238, 0.25);
  border-radius: var(--radius-sm);
  padding: 12px 16px;
  font-size: 0.85rem;
  color: #e0f2fe;
  line-height: 1.55;
  margin-bottom: 20px;
}

.tip-badge {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 800;
  background: rgba(34, 211, 238, 0.2);
  color: var(--accent-cyan);
  padding: 2px 6px;
  border-radius: 4px;
  white-space: nowrap;
}

/* Styled Details (Accordion) */
.styled-details {
  background: rgba(0, 0, 0, 0.25);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: all 0.2s ease;
}

.styled-details[open] {
  border-color: rgba(34, 211, 238, 0.3);
  background: rgba(0, 0, 0, 0.45);
}

.details-summary {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 18px;
  cursor: pointer;
  user-select: none;
  font-size: 0.88rem;
  font-weight: 600;
  color: #93c5fd;
  list-style: none;
}

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

.details-summary:hover {
  color: var(--accent-cyan);
  background: rgba(255, 255, 255, 0.02);
}

.summary-icon {
  font-size: 1.1rem;
}

.summary-text {
  flex: 1;
}

.summary-arrow {
  font-size: 0.7rem;
  color: var(--text-muted);
  transition: transform 0.25s ease;
}

.styled-details[open] .summary-arrow {
  transform: rotate(180deg);
  color: var(--accent-cyan);
}

.details-body {
  padding: 16px 20px 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  font-size: 0.85rem;
  color: #cbd5e1;
  line-height: 1.65;
}

/* ==============================================
   Interactive Architecture & Packet Map Simulator
   ============================================== */
.packet-map-section {
  margin-bottom: 48px;
}

.packet-map-card {
  background: linear-gradient(180deg, rgba(34, 211, 238, 0.07), rgba(15, 23, 42, 0.85));
  border: 1px solid rgba(34, 211, 238, 0.35);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.45);
}

.packet-map-head {
  text-align: center;
  margin-bottom: 28px;
}

.map-badge-group {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
}

.map-badge {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--accent-cyan);
  background: rgba(34, 211, 238, 0.15);
  border: 1px solid rgba(34, 211, 238, 0.4);
  padding: 3px 10px;
  border-radius: 9999px;
  letter-spacing: 0.5px;
}

.map-live-tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 700;
  color: #34d399;
  background: rgba(16, 185, 129, 0.15);
  border: 1px solid rgba(16, 185, 129, 0.35);
  padding: 3px 8px;
  border-radius: 9999px;
}

.map-title {
  font-size: clamp(1.3rem, 2.8vw, 1.8rem);
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 10px;
  letter-spacing: -0.5px;
}

.map-desc {
  font-size: 0.95rem;
  color: var(--text-sub);
  max-width: 720px;
  margin: 0 auto 20px;
}

/* Simulation Controls */
.sim-controls {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-top: 14px;
}

.sim-label {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 700;
}

.btn-sim {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(0, 0, 0, 0.4);
  border: 1px solid var(--border-subtle);
  border-radius: 9999px;
  padding: 7px 14px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-sub);
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-sim:hover {
  background: rgba(255, 255, 255, 0.06);
  color: var(--text-main);
  border-color: rgba(255, 255, 255, 0.2);
}

.btn-sim.active {
  background: rgba(34, 211, 238, 0.15);
  border-color: var(--accent-cyan);
  color: #ffffff;
  box-shadow: 0 0 16px rgba(34, 211, 238, 0.35);
}

.sim-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}

.dot-green { background: #10b981; box-shadow: 0 0 8px #10b981; }
.dot-red { background: #f43f5e; box-shadow: 0 0 8px #f43f5e; }
.dot-orange { background: #f59e0b; box-shadow: 0 0 8px #f59e0b; }
.dot-purple { background: #c084fc; box-shadow: 0 0 8px #c084fc; }

/* Diagram Track & Nodes */
.packet-diagram-wrap {
  position: relative;
  margin: 32px 0 24px;
  overflow-x: auto;
  padding: 10px 4px 20px;
  scrollbar-width: thin;
}

.diagram-track {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-width: 860px;
  padding: 0 10px;
}

/* Central Wire / Data Line */
.track-line-bg {
  position: absolute;
  top: 36px;
  left: 40px;
  right: 40px;
  height: 4px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 9999px;
  z-index: 1;
}

.track-line-fill {
  height: 100%;
  width: 100%;
  background: linear-gradient(90deg, var(--accent-cyan), #38bdf8, var(--accent-emerald));
  box-shadow: 0 0 12px var(--accent-cyan);
  transition: width 0.3s ease;
}

.packet-particle {
  position: absolute;
  top: 50%;
  left: 0%;
  transform: translate(-50%, -50%);
  width: 14px;
  height: 14px;
  background: #ffffff;
  border-radius: 50%;
  box-shadow: 0 0 16px #38bdf8, 0 0 30px var(--accent-cyan);
  transition: left 0.4s cubic-bezier(0.16, 1, 0.3, 1);
  display: none;
}

.packet-particle.moving {
  display: block;
}

/* Diagram Node */
.diagram-node {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  cursor: pointer;
  width: 110px;
  transition: transform 0.2s ease;
}

.diagram-node:hover {
  transform: translateY(-4px);
}

.node-icon-box {
  width: 60px;
  height: 60px;
  background: var(--bg-surface);
  border: 2px solid var(--border-subtle);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  margin-bottom: 10px;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.4);
  transition: all 0.25s ease;
}

.diagram-node:hover .node-icon-box {
  border-color: rgba(34, 211, 238, 0.5);
  box-shadow: 0 0 20px rgba(34, 211, 238, 0.35);
}

.diagram-node.active .node-icon-box {
  border-color: var(--accent-cyan);
  background: rgba(34, 211, 238, 0.15);
  box-shadow: 0 0 24px rgba(34, 211, 238, 0.5);
}

.diagram-node.node-error .node-icon-box {
  border-color: #f43f5e;
  background: rgba(244, 63, 94, 0.2);
  box-shadow: 0 0 24px rgba(244, 63, 94, 0.6);
  animation: shake 0.4s ease-in-out;
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-5px); }
  75% { transform: translateX(5px); }
}

.node-name {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--text-main);
  white-space: nowrap;
}

.node-sub {
  font-size: 0.72rem;
  color: var(--text-muted);
  margin-top: 2px;
  white-space: nowrap;
}

.diagram-conn {
  z-index: 2;
  color: var(--text-muted);
  font-size: 0.8rem;
  opacity: 0.4;
}

/* Node Inspector Panel */
.node-inspector {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 24px;
  background: rgba(0, 0, 0, 0.45);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-md);
  padding: 24px;
  margin-bottom: 20px;
}

.insp-step-badge {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 800;
  color: var(--accent-cyan);
  letter-spacing: 1px;
  display: inline-block;
  margin-bottom: 6px;
}

.insp-title {
  font-size: 1.25rem;
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 10px;
}

.insp-desc {
  font-size: 0.9rem;
  color: #cbd5e1;
  line-height: 1.6;
}

.insp-desc code {
  background: rgba(34, 211, 238, 0.12);
  color: var(--accent-cyan);
  padding: 2px 6px;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.82rem;
}

.insp-right {
  display: flex;
  flex-direction: column;
  gap: 12px;
  border-left: 1px solid rgba(255, 255, 255, 0.08);
  padding-left: 24px;
  justify-content: center;
}

.insp-meta-box {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.meta-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-weight: 600;
}

.meta-val {
  font-size: 0.85rem;
  color: var(--text-main);
  font-weight: 600;
}

.err-color {
  color: #fda4af;
}

.btn-goto-chapter {
  display: inline-flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 14px;
  background: rgba(34, 211, 238, 0.12);
  border: 1px solid rgba(34, 211, 238, 0.35);
  border-radius: var(--radius-sm);
  color: var(--accent-cyan);
  text-decoration: none;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 700;
  transition: all 0.2s ease;
  margin-top: 4px;
}

.btn-goto-chapter:hover {
  background: var(--accent-cyan);
  color: #060911;
  box-shadow: 0 0 14px rgba(34, 211, 238, 0.5);
}

/* Simulation Status Banner */
.sim-status-banner {
  display: flex;
  align-items: center;
  gap: 12px;
  background: rgba(0, 0, 0, 0.55);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 14px 20px;
  font-size: 0.9rem;
  color: #e2e8f0;
  transition: all 0.3s ease;
}

.sim-status-icon {
  font-size: 1.3rem;
  flex-shrink: 0;
}

.sim-status-banner.status-success {
  border-color: rgba(16, 185, 129, 0.4);
  background: rgba(16, 185, 129, 0.08);
  color: #6ee7b7;
}

.sim-status-banner.status-error {
  border-color: rgba(244, 63, 94, 0.4);
  background: rgba(244, 63, 94, 0.1);
  color: #fca5a5;
}

.sim-status-banner.status-warning {
  border-color: rgba(245, 158, 11, 0.4);
  background: rgba(245, 158, 11, 0.1);
  color: #fde68a;
}

/* Responsive Breakpoints */
@media (max-width: 860px) {
  .node-inspector {
    grid-template-columns: 1fr;
  }

  .insp-right {
    border-left: none;
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    padding-left: 0;
    padding-top: 16px;
  }

  .hero-metrics,
  .fact-grid,
  .analogy-grid,
  .error-code-grid,
  .ssl-choice-grid,
  .cloud-compare,
  .choice-guide-grid {
    grid-template-columns: 1fr;
  }

  .chapter-card {
    padding: 24px 20px;
  }

  .audit-card {
    padding: 24px 20px;
  }

  .ai-tool-grid {
    grid-template-columns: 1fr;
  }

  .workflow-steps {
    flex-direction: column;
    align-items: stretch;
  }

  .w-arrow {
    transform: rotate(90deg);
    text-align: center;
    margin: -4px 0;
  }

  .cf-breadcrumb-trail {
    flex-direction: column;
    align-items: stretch;
  }

  .trail-arrow {
    transform: rotate(90deg);
    text-align: center;
    margin: -2px 0;
  }

  .qs-roadmap-grid {
    grid-template-columns: 1fr;
  }

  .dc-input-group {
    flex-direction: column;
    align-items: stretch;
  }

  .iwinv-create-grid {
    grid-template-columns: 1fr;
  }

  .escape-grid {
    grid-template-columns: 1fr;
  }
}

/* AI Coding Tools Selection Guide */
.ai-tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 16px;
  margin: 22px 0 20px;
}

.ai-tool-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 22px 20px;
  display: flex;
  flex-direction: column;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
  overflow: hidden;
}

.ai-tool-card:hover {
  transform: translateY(-3px);
  border-color: rgba(255, 255, 255, 0.2);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.4);
}

.ai-tool-card.featured {
  border-color: rgba(34, 211, 238, 0.45);
  background: linear-gradient(180deg, rgba(34, 211, 238, 0.06) 0%, rgba(15, 23, 42, 0.8) 100%);
  box-shadow: 0 8px 24px rgba(6, 182, 212, 0.12);
}

.ai-tool-card.featured::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, #38bdf8, #818cf8);
}

.ai-tool-header {
  margin-bottom: 12px;
}

.ai-tool-badge-wrap {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
  flex-wrap: wrap;
}

.ai-tool-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 4px;
  letter-spacing: 0.02em;
}

.tag-agy {
  background: rgba(56, 189, 248, 0.15);
  color: #38bdf8;
  border: 1px solid rgba(56, 189, 248, 0.3);
}

.tag-cursor {
  background: rgba(168, 85, 247, 0.15);
  color: #c084fc;
  border: 1px solid rgba(168, 85, 247, 0.3);
}

.tag-claude {
  background: rgba(249, 115, 22, 0.15);
  color: #fb923c;
  border: 1px solid rgba(249, 115, 22, 0.3);
}

.ai-badge-recommend {
  font-size: 0.7rem;
  font-weight: 700;
  padding: 3px 8px;
  border-radius: 4px;
  background: rgba(16, 185, 129, 0.16);
  color: #34d399;
  border: 1px solid rgba(16, 185, 129, 0.35);
}

.ai-badge-sub {
  font-size: 0.7rem;
  padding: 3px 8px;
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.06);
  color: var(--text-sub);
}

.ai-tool-name {
  font-size: 1.15rem;
  font-weight: 800;
  color: #fff;
  letter-spacing: -0.01em;
}

.ai-sub {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-sub);
}

.ai-tool-role {
  font-size: 0.88rem;
  color: var(--text-sub);
  line-height: 1.45;
  margin-bottom: 14px;
  padding-bottom: 12px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.ai-tool-points {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: 0.84rem;
  line-height: 1.55;
  color: #cbd5e1;
}

.ai-tool-points li strong {
  color: #fff;
}

.ai-tool-points code {
  font-family: var(--font-mono);
  background: rgba(255, 255, 255, 0.08);
  padding: 2px 5px;
  border-radius: 3px;
  font-size: 0.78rem;
  color: var(--accent-cyan);
}

/* AI Workflow Synergy Box */
.ai-workflow-box {
  background: rgba(15, 23, 42, 0.8);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-sm);
  padding: 18px 20px;
  margin-top: 20px;
}

.workflow-header {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.92rem;
  color: #f1f5f9;
  margin-bottom: 14px;
}

.workflow-icon {
  font-size: 1.1rem;
}

.workflow-steps {
  display: flex;
  align-items: center;
  gap: 10px;
}

.w-step {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 6px;
  padding: 12px 14px;
  flex: 1;
}

.w-num {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent-cyan);
  color: #060911;
  font-family: var(--font-mono);
  font-weight: 800;
  font-size: 0.8rem;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-top: 2px;
}

.w-content {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.w-content strong {
  font-size: 0.85rem;
  color: #fff;
}

.w-content span {
  font-size: 0.78rem;
  color: var(--text-sub);
  line-height: 1.4;
}

.w-arrow {
  color: var(--accent-cyan);
  font-size: 1rem;
  opacity: 0.6;
  flex-shrink: 0;
}

/* Cloudflare Menu Guide & Breadcrumb */
.cf-menu-guide {
  border-color: rgba(34, 211, 238, 0.35);
  background: linear-gradient(180deg, rgba(34, 211, 238, 0.05) 0%, rgba(15, 23, 42, 0.7) 100%);
}

.cf-breadcrumb-trail {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 18px 0;
}

.trail-step {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  flex: 1;
  transition: all 0.2s ease;
}

.trail-step:hover {
  border-color: rgba(255, 255, 255, 0.2);
  background: rgba(255, 255, 255, 0.05);
}

.trail-step.highlight-step {
  border-color: rgba(34, 211, 238, 0.55);
  background: rgba(34, 211, 238, 0.09);
  box-shadow: 0 0 16px rgba(34, 211, 238, 0.15);
}

.trail-step.action-step {
  border-color: rgba(168, 85, 247, 0.55);
  background: rgba(168, 85, 247, 0.09);
}

.step-badge {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 800;
  color: var(--accent-cyan);
  background: rgba(34, 211, 238, 0.12);
  padding: 2px 7px;
  border-radius: 4px;
  margin-bottom: 6px;
}

.action-step .step-badge {
  color: #c084fc;
  background: rgba(168, 85, 247, 0.15);
}

.trail-name {
  font-size: 0.9rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 2px;
}

.trail-step small {
  font-size: 0.72rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.trail-arrow {
  color: var(--accent-cyan);
  font-size: 1rem;
  opacity: 0.6;
  flex-shrink: 0;
}

.cf-steps-detail {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 14px;
}

.cf-step-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 11px 14px;
  background: rgba(255, 255, 255, 0.025);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 6px;
}

.step-icon-num {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: rgba(34, 211, 238, 0.18);
  color: var(--accent-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-family: var(--font-mono);
  font-weight: 800;
  flex-shrink: 0;
  margin-top: 2px;
}

.step-text {
  display: flex;
  flex-direction: column;
  gap: 3px;
  font-size: 0.85rem;
  line-height: 1.45;
  color: #cbd5e1;
}

.step-text strong {
  color: #fff;
}

.step-text code {
  font-family: var(--font-mono);
  background: rgba(255, 255, 255, 0.08);
  padding: 1px 5px;
  border-radius: 3px;
  font-size: 0.8rem;
  color: var(--accent-cyan);
}

.step-text span {
  font-size: 0.78rem;
  color: var(--text-sub);
}

.cf-shortcut-box {
  margin-top: 16px;
  padding: 12px 16px;
  background: rgba(15, 23, 42, 0.85);
  border: 1px dashed rgba(34, 211, 238, 0.35);
  border-radius: 6px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.shortcut-tag {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--accent-cyan);
}

.cf-shortcut-box code {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: #f1f5f9;
  line-height: 1.4;
}

/* ========================================================
   Quickstart 10-Minute Mission & Domain Customizer Styles
   ======================================================== */
.quickstart-section {
  margin: 36px 0 28px;
}

.quickstart-card {
  background: linear-gradient(135deg, rgba(15, 23, 42, 0.95) 0%, rgba(8, 47, 73, 0.4) 100%);
  border: 1px solid rgba(34, 211, 238, 0.35);
  border-radius: var(--radius-lg);
  padding: 30px 28px;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.4), 0 0 24px rgba(6, 182, 212, 0.08);
  position: relative;
  overflow: hidden;
}

.quickstart-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-cyan), #818cf8, #34d399);
}

.qs-badge-wrap {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
}

.qs-badge {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--accent-cyan);
  background: rgba(34, 211, 238, 0.12);
  border: 1px solid rgba(34, 211, 238, 0.35);
  padding: 3px 10px;
  border-radius: 4px;
}

.qs-tag {
  font-size: 0.75rem;
  font-weight: 700;
  color: #34d399;
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid rgba(16, 185, 129, 0.3);
  padding: 3px 10px;
  border-radius: 4px;
}

.qs-title {
  font-size: 1.45rem;
  font-weight: 800;
  color: #fff;
  line-height: 1.4;
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.qs-desc {
  font-size: 0.92rem;
  color: #cbd5e1;
  line-height: 1.6;
  margin-bottom: 22px;
}

/* Domain Customizer Bar */
.domain-customizer-bar {
  background: rgba(0, 0, 0, 0.55);
  border: 1px solid rgba(34, 211, 238, 0.3);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  margin-bottom: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.dc-input-group {
  display: flex;
  align-items: center;
  gap: 10px;
}

.dc-prefix {
  font-size: 0.92rem;
  font-weight: 800;
  color: #38bdf8;
  white-space: nowrap;
}

.dc-input {
  flex: 1;
  background: rgba(15, 23, 42, 0.9);
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  color: #fff;
  font-family: var(--font-mono);
  font-size: 0.92rem;
  outline: none;
  transition: all 0.2s ease;
}

.dc-input:focus {
  border-color: var(--accent-cyan);
  box-shadow: 0 0 14px rgba(34, 211, 238, 0.3);
}

.btn-apply-dc {
  background: var(--accent-cyan);
  color: #060911;
  border: none;
  border-radius: var(--radius-sm);
  padding: 10px 18px;
  font-family: var(--font-sans);
  font-size: 0.88rem;
  font-weight: 800;
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.2s ease;
}

.btn-apply-dc:hover {
  background: #67e8f9;
  box-shadow: 0 0 14px rgba(34, 211, 238, 0.5);
}

.btn-reset-dc {
  background: rgba(255, 255, 255, 0.08);
  color: var(--text-sub);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  font-size: 0.82rem;
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.2s ease;
}

.btn-reset-dc:hover {
  background: rgba(255, 255, 255, 0.15);
  color: #fff;
}

.dc-status {
  font-size: 0.86rem;
  color: var(--text-sub);
}

.dynamic-test-domain-highlight {
  color: #38bdf8;
  font-family: var(--font-mono);
  background: rgba(6, 182, 212, 0.14);
  padding: 2px 7px;
  border-radius: 4px;
  border: 1px solid rgba(6, 182, 212, 0.25);
}

/* 5-Step Roadmap Grid */
.qs-roadmap-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 12px;
  margin-bottom: 24px;
}

.qs-step-card {
  background: rgba(255, 255, 255, 0.025);
  border: 1px solid rgba(255, 255, 255, 0.07);
  border-radius: var(--radius-sm);
  padding: 16px 14px;
  display: flex;
  flex-direction: column;
  transition: all 0.25s ease;
}

.qs-step-card:hover {
  border-color: rgba(255, 255, 255, 0.2);
  background: rgba(255, 255, 255, 0.045);
}

.qs-step-card.highlight {
  border-color: rgba(168, 85, 247, 0.45);
  background: linear-gradient(180deg, rgba(168, 85, 247, 0.07) 0%, rgba(15, 23, 42, 0.5) 100%);
}

.qs-step-card.success {
  border-color: rgba(16, 185, 129, 0.45);
  background: linear-gradient(180deg, rgba(16, 185, 129, 0.07) 0%, rgba(15, 23, 42, 0.5) 100%);
}

.qs-step-head {
  margin-bottom: 8px;
}

.qs-num {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 800;
  color: var(--accent-cyan);
  display: block;
  margin-bottom: 4px;
}

.qs-step-card.highlight .qs-num {
  color: #c084fc;
}

.qs-step-card.success .qs-num {
  color: #34d399;
}

.qs-step-head h4 {
  font-size: 0.92rem;
  font-weight: 700;
  color: #fff;
  line-height: 1.35;
}

.qs-step-card p {
  font-size: 0.82rem;
  color: #cbd5e1;
  line-height: 1.45;
  flex: 1;
}

.qs-tip {
  display: block;
  margin-top: 10px;
  font-size: 0.74rem;
  color: var(--text-muted);
  line-height: 1.35;
}

.qs-step-card.highlight .qs-tip {
  color: #e9d5ff;
}

.qs-step-card.success .qs-tip {
  color: #a7f3d0;
}

.qs-prompt-box {
  margin-top: 0;
}

.prompt-head-left {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.prompt-sub-desc {
  font-size: 0.78rem;
  color: var(--text-sub);
}

.badge-tag-sm {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  background: rgba(16, 185, 129, 0.15);
  color: #34d399;
  border: 1px solid rgba(16, 185, 129, 0.3);
  padding: 1px 5px;
  border-radius: 3px;
  margin-left: 4px;
  font-weight: 700;
}

/* iwinv Server Creation Guide Styles */
.iwinv-create-box {
  border-color: rgba(34, 211, 238, 0.35);
  background: linear-gradient(180deg, rgba(34, 211, 238, 0.04) 0%, rgba(15, 23, 42, 0.7) 100%);
}

.iwinv-create-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 14px;
  margin-top: 18px;
}

.iwinv-step-card {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 18px 16px;
  display: flex;
  flex-direction: column;
  transition: all 0.2s ease;
}

.iwinv-step-card:hover {
  border-color: rgba(255, 255, 255, 0.2);
  background: rgba(255, 255, 255, 0.05);
}

.iwinv-step-card.highlight-os {
  border-color: rgba(34, 211, 238, 0.55);
  background: rgba(34, 211, 238, 0.08);
  box-shadow: 0 0 16px rgba(34, 211, 238, 0.12);
}

.iwinv-step-badge {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 800;
  color: var(--accent-cyan);
  background: rgba(34, 211, 238, 0.12);
  padding: 2px 8px;
  border-radius: 4px;
  display: inline-block;
  margin-bottom: 8px;
  width: fit-content;
}

.iwinv-step-card h4 {
  font-size: 0.95rem;
  font-weight: 800;
  color: #fff;
  margin-bottom: 6px;
}

.iwinv-step-card p {
  font-size: 0.83rem;
  color: #cbd5e1;
  line-height: 1.5;
  margin: 0;
}

.os-reason {
  margin-top: 10px;
  padding: 8px 10px;
  background: rgba(0, 0, 0, 0.35);
  border-radius: 4px;
  font-size: 0.78rem;
  color: #a5f3fc;
  line-height: 1.45;
  border-left: 2px solid var(--accent-cyan);
}

/* Root Password Security Box Styles */
.root-security-box {
  border-color: rgba(244, 63, 94, 0.45);
  background: linear-gradient(180deg, rgba(244, 63, 94, 0.08) 0%, rgba(15, 23, 42, 0.8) 100%);
}

.root-danger-list {
  margin: 12px 0 16px;
  padding-left: 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 0.84rem;
  color: #fecdd3;
  line-height: 1.5;
}

.root-danger-list strong {
  color: #fff;
}

.root-action-box {
  background: rgba(16, 185, 129, 0.08);
  border: 1px solid rgba(16, 185, 129, 0.35);
  border-radius: var(--radius-sm);
  padding: 16px 18px;
  margin-top: 14px;
}

.action-title {
  display: block;
  font-size: 0.9rem;
  font-weight: 800;
  color: #34d399;
  margin-bottom: 8px;
}

.action-steps {
  margin: 0;
  padding-left: 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 0.83rem;
  color: #e2e8f0;
  line-height: 1.5;
}

.action-steps strong {
  color: #6ee7b7;
}

/* Quickstart Jump Button */
.btn-qs-jump {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 12px;
  background: rgba(168, 85, 247, 0.2);
  border: 1px solid rgba(168, 85, 247, 0.45);
  border-radius: var(--radius-sm);
  color: #e9d5ff;
  font-size: 0.78rem;
  font-weight: 700;
  text-decoration: none;
  margin-top: 10px;
  transition: all 0.2s ease;
  width: 100%;
}

.btn-qs-jump:hover {
  background: rgba(168, 85, 247, 0.35);
  color: #fff;
  box-shadow: 0 0 12px rgba(168, 85, 247, 0.3);
}

/* Self-Ban Escape & AWS Key Standard Styles */
.self-ban-escape-box {
  border-color: rgba(245, 158, 11, 0.35);
  background: linear-gradient(180deg, rgba(245, 158, 11, 0.05) 0%, rgba(15, 23, 42, 0.7) 100%);
}

.escape-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 14px;
  margin-top: 14px;
}

.escape-card {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 16px 14px;
  display: flex;
  flex-direction: column;
  transition: all 0.2s ease;
}

.escape-card:hover {
  border-color: rgba(255, 255, 255, 0.2);
  background: rgba(255, 255, 255, 0.05);
}

.esc-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 800;
  color: #f59e0b;
  background: rgba(245, 158, 11, 0.12);
  border: 1px solid rgba(245, 158, 11, 0.3);
  padding: 2px 8px;
  border-radius: 4px;
  display: inline-block;
  margin-bottom: 8px;
  width: fit-content;
}

.escape-card h4 {
  font-size: 0.92rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 6px;
}

.escape-card p {
  font-size: 0.83rem;
  color: #cbd5e1;
  line-height: 1.5;
  margin: 0;
}

.aws-key-standard-box {
  border-color: rgba(34, 211, 238, 0.35);
}

/* ========================================================
   Reading Mode Guide & Global Accordion Controller Styles
   ======================================================== */
.reading-guide-section {
  margin: 32px 0 28px;
}

.reading-guide-card {
  background: linear-gradient(135deg, rgba(15, 23, 42, 0.96) 0%, rgba(20, 30, 60, 0.7) 100%);
  border: 1px solid rgba(168, 85, 247, 0.4);
  border-radius: var(--radius-lg);
  padding: 28px 26px;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.4), 0 0 24px rgba(168, 85, 247, 0.08);
  position: relative;
  overflow: hidden;
}

.reading-guide-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, #c084fc, #38bdf8, #34d399);
}

.rg-header {
  margin-bottom: 22px;
}

.rg-badge-wrap {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 10px;
}

.rg-badge {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 800;
  color: #c084fc;
  background: rgba(168, 85, 247, 0.15);
  border: 1px solid rgba(168, 85, 247, 0.35);
  padding: 3px 10px;
  border-radius: var(--radius-sm);
  letter-spacing: 0.04em;
}

.rg-tag {
  font-size: 0.75rem;
  color: var(--text-sub);
  background: rgba(255, 255, 255, 0.05);
  padding: 3px 10px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
}

.rg-title {
  font-size: 1.35rem;
  font-weight: 800;
  color: #fff;
  letter-spacing: -0.02em;
  margin-bottom: 8px;
}

.rg-desc {
  font-size: 0.9rem;
  color: #cbd5e1;
  line-height: 1.6;
}

.rg-steps-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 22px;
}

.rg-step-box {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 18px 18px;
  display: flex;
  flex-direction: column;
  transition: all 0.2s ease;
}

.rg-step-box:hover {
  border-color: rgba(255, 255, 255, 0.18);
  background: rgba(255, 255, 255, 0.05);
}

.rg-step-box.step-1 {
  border-color: rgba(56, 189, 248, 0.3);
  background: linear-gradient(180deg, rgba(56, 189, 248, 0.06) 0%, rgba(15, 23, 42, 0.4) 100%);
}

.rg-step-box.step-2 {
  border-color: rgba(16, 185, 129, 0.3);
  background: linear-gradient(180deg, rgba(16, 185, 129, 0.06) 0%, rgba(15, 23, 42, 0.4) 100%);
}

.rg-step-head {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
}

.rg-step-num {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 800;
  padding: 3px 8px;
  border-radius: 4px;
}

.step-1 .rg-step-num {
  color: #38bdf8;
  background: rgba(56, 189, 248, 0.15);
  border: 1px solid rgba(56, 189, 248, 0.35);
}

.step-2 .rg-step-num {
  color: #34d399;
  background: rgba(16, 185, 129, 0.15);
  border: 1px solid rgba(16, 185, 129, 0.35);
}

.rg-step-head h4 {
  font-size: 0.98rem;
  font-weight: 800;
  color: #fff;
}

.rg-step-box p {
  font-size: 0.84rem;
  color: #cbd5e1;
  line-height: 1.55;
  flex: 1;
  margin-bottom: 12px;
}

.rg-step-action {
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding-top: 10px;
}

.rg-tip {
  font-size: 0.78rem;
  color: #94a3b8;
  line-height: 1.45;
  display: block;
}

.step-1 .rg-tip strong {
  color: #7dd3fc;
}

.step-2 .rg-tip strong {
  color: #6ee7b7;
}

/* Global Controller Bar */
.rg-controller-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 18px;
  background: rgba(0, 0, 0, 0.55);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-sm);
  flex-wrap: wrap;
}

.rg-status-text {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: #e2e8f0;
}

.status-indicator-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #38bdf8;
  box-shadow: 0 0 8px #38bdf8;
  transition: all 0.3s ease;
}

.status-indicator-dot.dot-expanded {
  background: #10b981;
  box-shadow: 0 0 8px #10b981;
}

.rg-button-group {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.btn-rg-mode {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: #cbd5e1;
  font-family: var(--font-sans);
  font-size: 0.82rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-rg-mode:hover {
  background: rgba(255, 255, 255, 0.12);
  color: #fff;
  border-color: rgba(255, 255, 255, 0.3);
}

.btn-rg-mode.active {
  background: linear-gradient(135deg, rgba(34, 211, 238, 0.25) 0%, rgba(16, 185, 129, 0.25) 100%);
  border-color: var(--accent-cyan);
  color: #fff;
  box-shadow: 0 0 14px rgba(34, 211, 238, 0.3);
}

.btn-rg-mode .mode-icon {
  font-size: 0.95rem;
}

/* 1회독 핵심 요약 오버뷰 박스 */
.chapter-overview-box {
  background: linear-gradient(180deg, rgba(34, 211, 238, 0.07) 0%, rgba(15, 23, 42, 0.6) 100%);
  border: 1px solid rgba(34, 211, 238, 0.25);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  margin-bottom: 20px;
}

.overview-title {
  font-size: 0.92rem;
  font-weight: 800;
  color: #38bdf8;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.chapter-overview-box p {
  font-size: 0.85rem;
  color: #cbd5e1;
  line-height: 1.6;
  margin: 0;
}

.chapter-overview-box code {
  font-family: var(--font-mono);
  background: rgba(255, 255, 255, 0.08);
  padding: 1px 5px;
  border-radius: 3px;
  color: var(--accent-cyan);
  font-size: 0.82rem;
}

/* Chapter Details Accordion Component */
.chapter-details {
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-sm);
  background: rgba(10, 16, 30, 0.5);
  margin-top: 14px;
  transition: all 0.25s ease;
  overflow: hidden;
}

.chapter-details[open] {
  border-color: rgba(34, 211, 238, 0.4);
  background: rgba(12, 20, 36, 0.7);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.35);
}

.chapter-details-summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 16px 20px;
  cursor: pointer;
  user-select: none;
  background: rgba(255, 255, 255, 0.02);
  transition: all 0.2s ease;
  list-style: none;
}

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

.chapter-details-summary:hover {
  background: rgba(34, 211, 238, 0.06);
}

.chapter-details[open] .chapter-details-summary {
  background: rgba(34, 211, 238, 0.08);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.cds-left {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 1;
}

.cds-icon {
  font-size: 1.15rem;
  color: var(--accent-cyan);
  flex-shrink: 0;
}

.cds-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: #f1f5f9;
  letter-spacing: -0.01em;
}

.chapter-details-summary:hover .cds-title {
  color: var(--accent-cyan);
}

.cds-badge {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 800;
  color: #34d399;
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid rgba(16, 185, 129, 0.3);
  padding: 2px 8px;
  border-radius: 4px;
  white-space: nowrap;
}

.cds-arrow {
  font-size: 0.75rem;
  color: var(--text-muted);
  transition: transform 0.25s ease;
  flex-shrink: 0;
}

.chapter-details[open] .cds-arrow {
  transform: rotate(180deg);
  color: var(--accent-cyan);
}

.chapter-details-body {
  padding: 20px 20px 24px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

/* Adjustments inside accordion to fit seamlessly */
.chapter-details-body .concept-box,
.chapter-details-body .operator-pick-box,
.chapter-details-body .prompt-box,
.chapter-details-body .security-box,
.chapter-details-body .compare-table-box {
  margin-top: 0;
}

@media (max-width: 860px) {
  .rg-steps-grid {
    grid-template-columns: 1fr;
  }

  .rg-controller-bar {
    flex-direction: column;
    align-items: stretch;
  }

  .rg-button-group {
    flex-direction: column;
  }

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

  .chapter-details-summary {
    padding: 14px 16px;
  }

  .cds-title {
    font-size: 0.88rem;
  }

  .chapter-details-body {
    padding: 16px 14px 20px;
  }
}

/* ==============================================
   1:1 Inquiry & Feedback System Styles
   ============================================== */
.header-right-group {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}

.btn-header-feedback {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(0, 242, 254, 0.08);
  border: 1px solid rgba(0, 242, 254, 0.35);
  color: #00f2fe;
  font-family: var(--font-sans);
  font-size: 0.8rem;
  font-weight: 700;
  padding: 6px 12px;
  border-radius: 20px;
  cursor: pointer;
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  text-decoration: none;
  backdrop-filter: blur(8px);
  white-space: nowrap;
  flex-shrink: 0;
}

.btn-header-feedback:hover {
  background: rgba(0, 242, 254, 0.18);
  border-color: #00f2fe;
  box-shadow: 0 0 16px rgba(0, 242, 254, 0.3);
  transform: translateY(-1px);
}

.btn-header-feedback .fb-icon {
  font-size: 0.95rem;
}

/* 1:1 Inquiry & Feedback Banner Section */
.inquiry-banner-section {
  margin: 50px 0 20px;
}

.inquiry-banner-card {
  position: relative;
  background: linear-gradient(135deg, rgba(16, 26, 46, 0.85), rgba(9, 14, 26, 0.95));
  border: 1px solid rgba(0, 242, 254, 0.3);
  border-radius: var(--radius-lg);
  padding: 28px 32px;
  overflow: hidden;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.4), 0 0 24px rgba(0, 242, 254, 0.1);
}

.inquiry-card-glow {
  position: absolute;
  top: -40px;
  right: -40px;
  width: 200px;
  height: 200px;
  background: radial-gradient(circle, rgba(0, 242, 254, 0.2), transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

.inquiry-card-inner {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  z-index: 1;
}

.inquiry-left {
  flex: 1;
}

.inquiry-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 800;
  color: #00f2fe;
  background: rgba(0, 242, 254, 0.12);
  border: 1px solid rgba(0, 242, 254, 0.3);
  border-radius: 4px;
  padding: 3px 8px;
  letter-spacing: 0.5px;
  margin-bottom: 10px;
}

.inquiry-title {
  font-size: 1.25rem;
  font-weight: 800;
  color: #ffffff;
  margin: 0 0 8px 0;
  letter-spacing: -0.3px;
  line-height: 1.4;
}

.inquiry-desc {
  font-size: 0.88rem;
  color: var(--text-sub);
  margin: 0;
  line-height: 1.6;
}

.inquiry-right {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 10px;
  flex-shrink: 0;
}

.btn-inquiry-open {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: linear-gradient(135deg, #00f2fe, #00b4d8);
  color: #030712;
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 800;
  padding: 12px 22px;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  box-shadow: 0 8px 24px rgba(0, 242, 254, 0.35);
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
  white-space: nowrap;
}

.btn-inquiry-open:hover {
  transform: translateY(-2px) scale(1.02);
  box-shadow: 0 12px 30px rgba(0, 242, 254, 0.55);
}

.btn-inquiry-open .btn-arrow {
  transition: transform 0.2s ease;
}

.btn-inquiry-open:hover .btn-arrow {
  transform: translateX(4px);
}

.link-admin-jump {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--text-muted);
  text-decoration: none;
  opacity: 0.75;
  transition: opacity 0.2s ease, color 0.2s ease;
}

.link-admin-jump:hover {
  opacity: 1;
  color: #00f2fe;
}

.footer-fb-link {
  color: #00f2fe !important;
  font-weight: 700;
}

.footer-admin-link {
  color: var(--text-muted) !important;
  opacity: 0.65;
}

.footer-admin-link:hover {
  opacity: 1;
  color: #00f2fe !important;
}

@media (max-width: 768px) {
  .inquiry-card-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 18px;
  }
  .inquiry-right {
    width: 100%;
    align-items: stretch;
  }
  .btn-inquiry-open {
    justify-content: center;
    width: 100%;
  }
  .link-admin-jump {
    text-align: center;
  }
}

/* Responsive Global Top Header */
@media (max-width: 860px) {
  .hub-header {
    padding: 12px 16px;
    margin-bottom: 24px;
    gap: 12px;
  }

  .header-left {
    gap: 10px;
    min-width: 0;
  }

  .brand-sub {
    display: none;
  }

  .brand-title {
    font-size: 0.95rem;
  }

  .header-status {
    display: none;
  }

  .btn-header-feedback {
    padding: 6px 11px;
    font-size: 0.78rem;
  }

  .fb-extra {
    display: none;
  }
}

@media (max-width: 640px) {
  .layout-container {
    padding: 16px 14px 60px;
  }

  .hub-header {
    padding: 10px 14px;
    gap: 10px;
    border-radius: 14px;
  }

  .header-left {
    gap: 8px;
  }

  .btn-back {
    padding: 5px 10px;
    font-size: 0.8rem;
    gap: 5px;
  }

  .back-sub {
    display: none;
  }

  .brand-divider {
    opacity: 0.35;
    font-size: 0.85rem;
  }

  .brand-title {
    font-size: 0.9rem;
    letter-spacing: -0.3px;
  }

  .btn-header-feedback {
    padding: 5px 10px;
    font-size: 0.76rem;
    gap: 5px;
  }

  .btn-header-feedback .fb-icon {
    font-size: 0.85rem;
  }
}

@media (max-width: 375px) {
  .layout-container {
    padding: 14px 10px 60px;
  }

  .hub-header {
    padding: 8px 10px;
    gap: 6px;
    border-radius: 12px;
  }

  .header-left {
    gap: 6px;
  }

  .btn-back {
    padding: 4px 7px;
    font-size: 0.74rem;
    gap: 3px;
  }

  .brand-divider {
    font-size: 0.75rem;
    margin: 0 -2px;
  }

  .brand-title {
    font-size: 0.82rem;
  }

  .btn-header-feedback {
    padding: 4px 8px;
    font-size: 0.72rem;
    gap: 4px;
  }
}