/* ==========================================================================
   Proton VPN 实验室 (ProtonVPN Labs) - 旗舰专业设计系统
   Brand Color Palette: Deep Space Obsidian, Proton Purple, Swiss Emerald
   ========================================================================== */

:root {
  --bg-dark: #0B0C15;
  --bg-card: #121424;
  --bg-card-hover: #191D34;
  --bg-card-elevated: #16192E;
  --border-subtle: #222646;
  --border-glow: #6D4AFF;
  
  --proton-purple: #6D4AFF;
  --proton-purple-light: #8A63FF;
  --proton-purple-glow: rgba(109, 74, 255, 0.35);
  --proton-purple-faint: rgba(109, 74, 255, 0.12);
  
  --proton-green: #00D287;
  --proton-green-light: #34E8A3;
  --proton-green-glow: rgba(0, 210, 135, 0.3);
  --proton-green-faint: rgba(0, 210, 135, 0.12);
  
  --proton-cyan: #38E1FF;
  --proton-red: #FF4F64;
  --proton-amber: #FFAE33;
  
  --text-main: #F1F4F9;
  --text-secondary: #94A3B8;
  --text-muted: #64748B;
  
  --font-sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'Fira Code', 'JetBrains Mono', 'Courier New', monospace;
  
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --radius-full: 9999px;
  
  --transition-fast: 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-smooth: 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  --shadow-card: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
  --shadow-glow: 0 0 35px -5px var(--proton-purple-glow);
}

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

html {
  scroll-behavior: smooth;
  font-family: var(--font-sans);
  background-color: var(--bg-dark);
  color: var(--text-main);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

body {
  overflow-x: hidden;
  min-height: 100vh;
  position: relative;
  background-color: var(--bg-dark);
}

/* Background Grids & Ambient Lights */
.ambient-bg {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.ambient-glow-1 {
  position: absolute;
  top: -10%;
  left: 30%;
  width: 700px;
  height: 700px;
  background: radial-gradient(circle, rgba(109, 74, 255, 0.18) 0%, rgba(11, 12, 21, 0) 70%);
  filter: blur(80px);
}

.ambient-glow-2 {
  position: absolute;
  top: 40%;
  right: -10%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(0, 210, 135, 0.12) 0%, rgba(11, 12, 21, 0) 70%);
  filter: blur(90px);
}

.ambient-glow-3 {
  position: absolute;
  bottom: 5%;
  left: 10%;
  width: 800px;
  height: 800px;
  background: radial-gradient(circle, rgba(109, 74, 255, 0.14) 0%, rgba(11, 12, 21, 0) 75%);
  filter: blur(100px);
}

.grid-overlay {
  position: absolute;
  inset: 0;
  background-image: 
    linear-gradient(to right, rgba(255, 255, 255, 0.03) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse at 50% 30%, rgba(0, 0, 0, 1) 0%, rgba(0, 0, 0, 0.1) 85%);
  -webkit-mask-image: radial-gradient(ellipse at 50% 30%, rgba(0, 0, 0, 1) 0%, rgba(0, 0, 0, 0.1) 85%);
}

/* Typography Helpers */
a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-fast);
}

h1, h2, h3, h4, h5, h6 {
  color: #FFFFFF;
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.02em;
}

code, .font-mono {
  font-family: var(--font-mono);
}

.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

/* Top Promo Bar */
.top-bar {
  background: linear-gradient(90deg, #181135 0%, #29165B 50%, #152A28 100%);
  border-bottom: 1px solid rgba(109, 74, 255, 0.3);
  padding: 10px 16px;
  font-size: 0.85rem;
  color: #E2E8F0;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  position: relative;
  z-index: 60;
  flex-wrap: wrap;
}

.top-bar .badge {
  background: rgba(0, 210, 135, 0.2);
  color: var(--proton-green);
  border: 1px solid rgba(0, 210, 135, 0.4);
  padding: 3px 10px;
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: 0.75rem;
  display: inline-flex;
  align-items: center;
  gap: 5px;
}

.top-bar .highlight {
  color: #FFFFFF;
  font-weight: 700;
}

.top-bar .top-cta {
  color: #FFFFFF;
  background: var(--proton-purple);
  padding: 4px 14px;
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: 0.8rem;
  transition: all var(--transition-fast);
  box-shadow: 0 0 15px rgba(109, 74, 255, 0.5);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.top-bar .top-cta:hover {
  background: var(--proton-purple-light);
  transform: translateY(-1px);
}

/* Navbar */
.navbar {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(11, 12, 21, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
  transition: background var(--transition-smooth), border-color var(--transition-smooth);
}

.navbar .nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav-brand .brand-logo {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}

.nav-brand .brand-text {
  display: flex;
  flex-direction: column;
}

.nav-brand .brand-name {
  font-size: 1.2rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: #FFFFFF;
  display: flex;
  align-items: center;
  gap: 6px;
}

.nav-brand .brand-tag {
  font-size: 0.68rem;
  text-transform: uppercase;
  font-family: var(--font-mono);
  color: var(--proton-green);
  font-weight: 600;
  letter-spacing: 0.05em;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-link {
  font-size: 0.92rem;
  color: var(--text-secondary);
  font-weight: 500;
  transition: color var(--transition-fast);
  display: flex;
  align-items: center;
  gap: 6px;
}

.nav-link:hover {
  color: #FFFFFF;
}

.nav-link.active {
  color: var(--proton-purple-light);
  font-weight: 600;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 14px;
}

/* Button Component System */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-weight: 600;
  border-radius: var(--radius-md);
  padding: 10px 22px;
  font-size: 0.92rem;
  cursor: pointer;
  transition: all var(--transition-smooth);
  border: 1px solid transparent;
  outline: none;
  white-space: nowrap;
}

.btn-sm {
  padding: 7px 15px;
  font-size: 0.82rem;
  border-radius: var(--radius-sm);
}

.btn-lg {
  padding: 14px 30px;
  font-size: 1.05rem;
  border-radius: var(--radius-md);
}

.btn-primary {
  background: linear-gradient(135deg, var(--proton-purple) 0%, #5733DC 100%);
  color: #FFFFFF;
  box-shadow: 0 4px 20px -2px var(--proton-purple-glow);
}

.btn-primary:hover {
  background: linear-gradient(135deg, var(--proton-purple-light) 0%, var(--proton-purple) 100%);
  box-shadow: 0 6px 28px 0px rgba(109, 74, 255, 0.55);
  transform: translateY(-2px);
  color: #FFFFFF;
}

.btn-green {
  background: linear-gradient(135deg, #00D287 0%, #00AB6E 100%);
  color: #0B0C15;
  font-weight: 700;
  box-shadow: 0 4px 20px -2px var(--proton-green-glow);
}

.btn-green:hover {
  background: linear-gradient(135deg, #34E8A3 0%, #00D287 100%);
  box-shadow: 0 6px 28px 0px rgba(0, 210, 135, 0.55);
  transform: translateY(-2px);
  color: #0B0C15;
}

.btn-outline {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-main);
  border-color: var(--border-subtle);
}

.btn-outline:hover {
  background: rgba(109, 74, 255, 0.1);
  border-color: var(--proton-purple);
  color: #FFFFFF;
  transform: translateY(-2px);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
}

.btn-ghost:hover {
  color: #FFFFFF;
  background: rgba(255, 255, 255, 0.06);
}

.btn-glow {
  position: relative;
  overflow: hidden;
}

.btn-glow::after {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.3) 0%, transparent 60%);
  opacity: 0;
  transition: opacity 0.3s;
  pointer-events: none;
}

.btn-glow:hover::after {
  opacity: 1;
}

.mobile-toggle {
  display: none;
  background: transparent;
  border: none;
  color: #FFFFFF;
  cursor: pointer;
  padding: 6px;
}

/* Hero Section */
.hero-section {
  padding: 60px 0 80px;
  position: relative;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
}

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: rgba(109, 74, 255, 0.14);
  border: 1px solid rgba(109, 74, 255, 0.35);
  border-radius: var(--radius-full);
  font-size: 0.8rem;
  color: #C084FC;
  font-family: var(--font-mono);
  font-weight: 600;
  margin-bottom: 24px;
}

.hero-tag .pulse-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--proton-green);
  box-shadow: 0 0 10px var(--proton-green);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% { transform: scale(0.95); opacity: 0.8; }
  50% { transform: scale(1.3); opacity: 1; box-shadow: 0 0 16px var(--proton-green); }
  100% { transform: scale(0.95); opacity: 0.8; }
}

.hero-title {
  font-size: 3.4rem;
  line-height: 1.15;
  letter-spacing: -0.035em;
  margin-bottom: 20px;
}

.gradient-text-purple {
  background: linear-gradient(135deg, #FFFFFF 20%, #BBA8FF 60%, var(--proton-purple-light) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.gradient-text-green {
  background: linear-gradient(135deg, #A7F3D0 0%, var(--proton-green) 50%, #00AB6E 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-description {
  font-size: 1.15rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 34px;
  max-width: 600px;
}

.hero-ctas {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 36px;
  flex-wrap: wrap;
}

.hero-guarantee {
  display: flex;
  align-items: center;
  gap: 20px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.hero-guarantee-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

.hero-guarantee-item svg {
  color: var(--proton-green);
}

/* Interactive Telemetry Box (Right Column of Hero) */
.telemetry-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow-card), 0 0 40px -10px var(--proton-purple-glow);
  position: relative;
  overflow: hidden;
}

.telemetry-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--proton-purple), var(--proton-green), transparent);
}

.telemetry-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--border-subtle);
}

.telemetry-header .title-badge {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.88rem;
  font-weight: 700;
  color: #FFFFFF;
}

.telemetry-header .live-badge {
  background: rgba(0, 210, 135, 0.15);
  border: 1px solid rgba(0, 210, 135, 0.4);
  color: var(--proton-green);
  font-size: 0.72rem;
  font-family: var(--font-mono);
  padding: 2px 8px;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  gap: 5px;
}

.telemetry-stats-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
  margin-bottom: 20px;
}

.stat-box {
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid rgba(255, 255, 255, 0.05);
  border-radius: var(--radius-md);
  padding: 12px 14px;
}

.stat-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-bottom: 4px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.stat-value {
  font-size: 1.15rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: #FFFFFF;
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.stat-unit {
  font-size: 0.75rem;
  color: var(--text-secondary);
}

/* Connection Toggle Interactive Switch */
.telemetry-interactive {
  background: var(--bg-card-elevated);
  border: 1px solid rgba(109, 74, 255, 0.25);
  border-radius: var(--radius-md);
  padding: 16px;
  margin-bottom: 18px;
}

.connection-status-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.connection-server {
  display: flex;
  align-items: center;
  gap: 10px;
}

.server-flag {
  font-size: 1.5rem;
  line-height: 1;
}

.server-details {
  display: flex;
  flex-direction: column;
}

.server-name {
  font-size: 0.9rem;
  font-weight: 700;
  color: #FFFFFF;
}

.server-ip {
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--proton-cyan);
}

.connect-switch-btn {
  padding: 8px 18px;
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 700;
  cursor: pointer;
  transition: all var(--transition-smooth);
  display: flex;
  align-items: center;
  gap: 6px;
  border: 1px solid transparent;
}

.connect-switch-btn.connected {
  background: rgba(0, 210, 135, 0.15);
  border-color: rgba(0, 210, 135, 0.5);
  color: var(--proton-green);
}

.connect-switch-btn.connected:hover {
  background: rgba(255, 79, 100, 0.15);
  border-color: rgba(255, 79, 100, 0.4);
  color: var(--proton-red);
}

.connect-switch-btn.disconnected {
  background: var(--proton-purple);
  color: #FFFFFF;
  box-shadow: 0 0 15px var(--proton-purple-glow);
}

.connect-switch-btn.disconnected:hover {
  background: var(--proton-purple-light);
}

.telemetry-route-visual {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 12px;
  background: rgba(0, 0, 0, 0.25);
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-family: var(--font-mono);
}

.route-step {
  display: flex;
  align-items: center;
  gap: 5px;
  color: var(--text-secondary);
}

.route-step.active {
  color: var(--proton-green);
  font-weight: 600;
}

.route-arrow {
  color: var(--text-muted);
  font-size: 0.7rem;
}

/* Section Header */
.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 56px;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 600;
  font-family: var(--font-mono);
  background: rgba(109, 74, 255, 0.12);
  border: 1px solid rgba(109, 74, 255, 0.3);
  color: #C084FC;
  margin-bottom: 16px;
  text-transform: uppercase;
}

.section-title {
  font-size: 2.5rem;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
}

.section-subtitle {
  font-size: 1.05rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Feature Grid - 6 Pillars */
.pillars-section {
  padding: 80px 0;
  position: relative;
}

.pillars-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.pillar-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: all var(--transition-smooth);
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.pillar-card:hover {
  background: var(--bg-card-hover);
  border-color: rgba(109, 74, 255, 0.4);
  transform: translateY(-5px);
  box-shadow: 0 15px 35px -10px rgba(0, 0, 0, 0.6), 0 0 25px -5px var(--proton-purple-glow);
}

.pillar-card-icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background: rgba(109, 74, 255, 0.12);
  border: 1px solid rgba(109, 74, 255, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--proton-purple-light);
  transition: all var(--transition-smooth);
}

.pillar-card:hover .pillar-card-icon {
  background: var(--proton-purple);
  color: #FFFFFF;
  box-shadow: 0 0 20px var(--proton-purple-glow);
}

.pillar-card-title {
  font-size: 1.25rem;
  margin-bottom: 12px;
}

.pillar-card-desc {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin-bottom: 20px;
  flex-grow: 1;
}

.pillar-tag {
  align-self: flex-start;
  font-size: 0.72rem;
  font-family: var(--font-mono);
  padding: 3px 9px;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.05);
  color: var(--proton-cyan);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

/* Interactive Lab Section (Four Testbeds) */
.labs-section {
  padding: 90px 0;
  position: relative;
  background: linear-gradient(180deg, transparent 0%, rgba(18, 20, 36, 0.4) 50%, transparent 100%);
}

.lab-tabs {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-bottom: 36px;
  flex-wrap: wrap;
}

.lab-tab-btn {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  padding: 10px 20px;
  border-radius: var(--radius-full);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  gap: 8px;
}

.lab-tab-btn:hover {
  color: #FFFFFF;
  border-color: rgba(109, 74, 255, 0.4);
}

.lab-tab-btn.active {
  background: var(--proton-purple);
  color: #FFFFFF;
  border-color: var(--proton-purple);
  box-shadow: 0 0 20px var(--proton-purple-glow);
}

.lab-content-box {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: 36px;
  box-shadow: var(--shadow-card);
  position: relative;
}

.lab-panel {
  display: none;
}

.lab-panel.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

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

/* Lab 1: Stealth DPI Inspector */
.dpi-compare-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
}

.dpi-card {
  background: var(--bg-card-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 22px;
}

.dpi-card.insecure {
  border-color: rgba(255, 79, 100, 0.3);
}

.dpi-card.secure {
  border-color: rgba(0, 210, 135, 0.4);
  box-shadow: 0 0 25px -5px var(--proton-green-glow);
}

.dpi-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.dpi-title {
  font-size: 1rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 8px;
}

.hex-dump-window {
  background: #07080F;
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-sm);
  padding: 14px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: #A0AEC0;
  height: 180px;
  overflow-y: auto;
  line-height: 1.7;
}

.hex-line {
  display: flex;
  gap: 12px;
}

.hex-offset {
  color: #4A5568;
}

.hex-bytes {
  color: #CBD5E0;
}

.hex-bytes.flagged {
  color: var(--proton-red);
  font-weight: 700;
  background: rgba(255, 79, 100, 0.15);
  padding: 0 4px;
  border-radius: 2px;
}

.hex-bytes.stealth {
  color: var(--proton-green);
  font-weight: 700;
  background: rgba(0, 210, 135, 0.15);
  padding: 0 4px;
  border-radius: 2px;
}

.dpi-verdict {
  margin-top: 14px;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  font-size: 0.82rem;
  display: flex;
  align-items: center;
  gap: 8px;
}

.dpi-verdict.fail {
  background: rgba(255, 79, 100, 0.1);
  color: #FFA2AE;
  border: 1px solid rgba(255, 79, 100, 0.25);
}

.dpi-verdict.pass {
  background: rgba(0, 210, 135, 0.1);
  color: #6EE7B7;
  border: 1px solid rgba(0, 210, 135, 0.25);
}

/* Lab 2: Secure Core Multi-hop Visualizer */
.topology-map {
  background: #080911;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 30px;
  margin-bottom: 24px;
  position: relative;
}

.topology-nodes {
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: relative;
  z-index: 2;
}

.node-box {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 18px 20px;
  text-align: center;
  min-width: 170px;
  transition: all var(--transition-smooth);
}

.node-box.bunker {
  border-color: var(--proton-purple);
  box-shadow: 0 0 25px -3px var(--proton-purple-glow);
}

.node-box.exit {
  border-color: var(--proton-green);
  box-shadow: 0 0 25px -3px var(--proton-green-glow);
}

.node-flag {
  font-size: 1.8rem;
  margin-bottom: 6px;
}

.node-name {
  font-size: 0.95rem;
  font-weight: 700;
  color: #FFFFFF;
}

.node-sub {
  font-size: 0.72rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
}

.connector-line {
  flex-grow: 1;
  height: 2px;
  background: linear-gradient(90deg, var(--proton-purple), var(--proton-green));
  position: relative;
  margin: 0 16px;
}

.packet-ping {
  position: absolute;
  top: -4px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: #FFFFFF;
  box-shadow: 0 0 10px #FFFFFF, 0 0 20px var(--proton-purple);
  animation: packetSlide 2.5s infinite linear;
}

@keyframes packetSlide {
  0% { left: 0%; opacity: 0; }
  10% { opacity: 1; }
  90% { opacity: 1; }
  100% { left: 100%; opacity: 0; }
}

/* Lab 3: Accelerator Benchmark Slider */
.slider-container {
  margin: 28px 0;
  background: var(--bg-card-elevated);
  padding: 20px;
  border-radius: var(--radius-md);
}

.slider-label-row {
  display: flex;
  justify-content: space-between;
  margin-bottom: 10px;
  font-size: 0.88rem;
  font-weight: 600;
}

.range-slider {
  width: 100%;
  height: 6px;
  border-radius: 3px;
  background: #252A4A;
  outline: none;
  -webkit-appearance: none;
}

.range-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--proton-purple-light);
  cursor: pointer;
  box-shadow: 0 0 12px var(--proton-purple);
}

.speed-comparison-bars {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-top: 24px;
}

.speed-bar-row {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.bar-header {
  display: flex;
  justify-content: space-between;
  font-size: 0.82rem;
  font-family: var(--font-mono);
}

.bar-track {
  height: 12px;
  background: #17192C;
  border-radius: 6px;
  overflow: hidden;
  position: relative;
}

.bar-fill {
  height: 100%;
  border-radius: 6px;
  transition: width 0.4s ease;
}

.bar-fill.legacy {
  background: #4A5568;
}

.bar-fill.accelerator {
  background: linear-gradient(90deg, var(--proton-purple), var(--proton-green));
  box-shadow: 0 0 15px var(--proton-green-glow);
}

/* Lab 4: Leak Detection Tool */
.leak-checker-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin: 24px 0;
}

.leak-item-card {
  background: var(--bg-card-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 16px;
  text-align: center;
}

.leak-status-icon {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  margin: 0 auto 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
}

.leak-status-icon.safe {
  background: rgba(0, 210, 135, 0.15);
  color: var(--proton-green);
  border: 1px solid rgba(0, 210, 135, 0.3);
}

.leak-item-name {
  font-size: 0.88rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.leak-item-result {
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--proton-green);
}

/* Global Mesh Section (Server Topology) */
.servers-section {
  padding: 80px 0;
}

.server-table-wrapper {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-top: 36px;
}

.server-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
}

.server-table th {
  background: rgba(255, 255, 255, 0.02);
  padding: 16px 20px;
  font-size: 0.78rem;
  text-transform: uppercase;
  font-family: var(--font-mono);
  color: var(--text-muted);
  border-bottom: 1px solid var(--border-subtle);
}

.server-table td {
  padding: 16px 20px;
  font-size: 0.9rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
  vertical-align: middle;
}

.server-table tr:hover td {
  background: rgba(109, 74, 255, 0.04);
}

.country-cell {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 600;
  color: #FFFFFF;
}

.latency-badge {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 3px 8px;
  border-radius: var(--radius-sm);
}

.latency-badge.ultra {
  background: rgba(0, 210, 135, 0.15);
  color: var(--proton-green);
}

.latency-badge.fast {
  background: rgba(56, 225, 255, 0.15);
  color: var(--proton-cyan);
}

.feature-pill {
  font-size: 0.72rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.08);
  padding: 2px 7px;
  border-radius: 4px;
  color: var(--text-secondary);
  display: inline-block;
  margin-right: 4px;
}

/* Pricing Section */
.pricing-section {
  padding: 90px 0;
  position: relative;
}

.billing-switch-wrapper {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 48px;
}

.billing-switch {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  padding: 4px;
  display: flex;
  gap: 4px;
}

.billing-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-weight: 600;
  font-size: 0.88rem;
  padding: 8px 20px;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  gap: 6px;
}

.billing-btn.active {
  background: var(--proton-purple);
  color: #FFFFFF;
  box-shadow: 0 0 15px var(--proton-purple-glow);
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
  align-items: stretch;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  padding: 36px 30px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: all var(--transition-smooth);
}

.pricing-card:hover {
  transform: translateY(-6px);
  border-color: rgba(109, 74, 255, 0.4);
  box-shadow: var(--shadow-card);
}

.pricing-card.featured {
  background: linear-gradient(180deg, #181A32 0%, #121424 100%);
  border: 2px solid var(--proton-purple);
  box-shadow: 0 0 40px -10px var(--proton-purple-glow), var(--shadow-card);
  transform: scale(1.03);
}

.pricing-card.featured:hover {
  transform: scale(1.03) translateY(-6px);
}

.featured-ribbon {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(90deg, var(--proton-purple) 0%, #00D287 100%);
  color: #FFFFFF;
  padding: 4px 16px;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  box-shadow: 0 4px 15px rgba(109, 74, 255, 0.4);
}

.plan-header {
  margin-bottom: 24px;
}

.plan-name {
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 6px;
}

.plan-sub {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.plan-price-box {
  display: flex;
  align-items: baseline;
  gap: 6px;
  margin-bottom: 8px;
}

.currency {
  font-size: 1.5rem;
  font-weight: 700;
  color: #FFFFFF;
}

.amount {
  font-size: 3.2rem;
  font-weight: 800;
  line-height: 1;
  font-family: var(--font-mono);
  color: #FFFFFF;
}

.period {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.discount-tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--proton-green);
  background: rgba(0, 210, 135, 0.15);
  border: 1px solid rgba(0, 210, 135, 0.3);
  padding: 2px 8px;
  border-radius: 4px;
  margin-bottom: 24px;
}

.plan-features-list {
  list-style: none;
  margin: 24px 0 32px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  flex-grow: 1;
}

.feature-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.feature-item svg {
  color: var(--proton-green);
  flex-shrink: 0;
  margin-top: 3px;
}

.feature-item.highlight-feature {
  color: #FFFFFF;
  font-weight: 600;
}

/* Audits & Trust Section */
.trust-section {
  padding: 80px 0;
  background: rgba(18, 20, 36, 0.3);
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}

.trust-badges-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.trust-badge-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 24px 20px;
  text-align: center;
  transition: all var(--transition-fast);
}

.trust-badge-card:hover {
  border-color: rgba(109, 74, 255, 0.35);
  transform: translateY(-3px);
}

.trust-badge-card .badge-icon {
  font-size: 2rem;
  margin-bottom: 12px;
}

.trust-badge-card h4 {
  font-size: 1.05rem;
  margin-bottom: 6px;
}

.trust-badge-card p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* FAQ Accordion */
.faq-section {
  padding: 90px 0;
}

.faq-container {
  max-width: 820px;
  margin: 0 auto;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  margin-bottom: 14px;
  overflow: hidden;
  transition: border-color var(--transition-fast);
}

.faq-item:hover {
  border-color: rgba(109, 74, 255, 0.3);
}

.faq-question {
  width: 100%;
  text-align: left;
  background: transparent;
  border: none;
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 1.05rem;
  font-weight: 600;
  color: #FFFFFF;
  cursor: pointer;
}

.faq-icon {
  width: 20px;
  height: 20px;
  color: var(--proton-purple-light);
  transition: transform var(--transition-fast);
}

.faq-item.active .faq-icon {
  transform: rotate(180deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease-out, padding 0.3s ease;
  padding: 0 24px;
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
}

.faq-item.active .faq-answer {
  max-height: 500px;
  padding: 0 24px 22px;
}

/* Sticky Bottom Bar */
.sticky-bottom-bar {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: rgba(11, 12, 21, 0.94);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-top: 1px solid rgba(109, 74, 255, 0.3);
  padding: 12px 20px;
  z-index: 40;
  box-shadow: 0 -10px 30px rgba(0, 0, 0, 0.5);
  transform: translateY(100%);
  transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.sticky-bottom-bar.visible {
  transform: translateY(0);
}

.sticky-content {
  max-width: 1240px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.sticky-info {
  display: flex;
  align-items: center;
  gap: 14px;
}

.sticky-badge {
  background: rgba(0, 210, 135, 0.2);
  color: var(--proton-green);
  border: 1px solid rgba(0, 210, 135, 0.4);
  padding: 4px 10px;
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 700;
}

.sticky-text {
  font-size: 0.9rem;
  color: #FFFFFF;
}

.sticky-price {
  font-family: var(--font-mono);
  font-weight: 800;
  color: var(--proton-green);
}

/* Footer */
.footer {
  background: #07080E;
  border-top: 1px solid var(--border-subtle);
  padding: 60px 0 30px;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr repeat(3, 1fr);
  gap: 40px;
  margin-bottom: 50px;
}

.footer-brand-col p {
  margin: 14px 0 20px;
  line-height: 1.6;
  max-width: 320px;
}

.footer-col h5 {
  font-size: 0.95rem;
  font-weight: 700;
  color: #FFFFFF;
  margin-bottom: 18px;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a:hover {
  color: #FFFFFF;
}

.footer-bottom {
  padding-top: 30px;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 0.8rem;
}

/* Mobile Drawer */
.mobile-drawer {
  position: fixed;
  inset: 0;
  background: rgba(11, 12, 21, 0.98);
  backdrop-filter: blur(20px);
  z-index: 100;
  padding: 30px 24px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transform: translateX(100%);
  transition: transform 0.35s ease;
}

.mobile-drawer.open {
  transform: translateX(0);
}

.drawer-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.drawer-close {
  background: transparent;
  border: none;
  color: #FFFFFF;
  cursor: pointer;
  padding: 8px;
}

.drawer-menu {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 20px;
  margin: 40px 0;
}

.drawer-link {
  font-size: 1.25rem;
  font-weight: 600;
  color: #FFFFFF;
}

/* Responsive Media Queries */
@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  
  .hero-title {
    font-size: 2.8rem;
  }
  
  .pillars-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .pricing-grid {
    grid-template-columns: 1fr;
    max-width: 480px;
    margin: 0 auto;
  }
  
  .pricing-card.featured {
    transform: none;
  }
  
  .pricing-card.featured:hover {
    transform: translateY(-6px);
  }
  
  .trust-badges-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  
  .dpi-compare-grid {
    grid-template-columns: 1fr;
  }
  
  .leak-checker-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-menu, .nav-actions .btn-outline {
    display: none;
  }
  
  .mobile-toggle {
    display: block;
  }
  
  .hero-title {
    font-size: 2.2rem;
  }
  
  .section-title {
    font-size: 1.9rem;
  }
  
  .pillars-grid {
    grid-template-columns: 1fr;
  }
  
  .trust-badges-grid {
    grid-template-columns: 1fr;
  }
  
  .topology-nodes {
    flex-direction: column;
    gap: 20px;
  }
  
  .connector-line {
    width: 2px;
    height: 40px;
    margin: 0 auto;
  }
  
  .packet-ping {
    top: 0;
    left: -4px;
    animation: packetSlideVertical 2s infinite linear;
  }
  
  @keyframes packetSlideVertical {
    0% { top: 0%; opacity: 0; }
    50% { opacity: 1; }
    100% { top: 100%; opacity: 0; }
  }
  
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }
  
  .sticky-info {
    display: none;
  }
  
  .sticky-content {
    justify-content: center;
  }
  
  .sticky-content .btn {
    width: 100%;
  }
}