/* ==========================================================================
   Open App Bridge (OAB) — Design System & Stylesheet
   Design Language: Material 3 Expressive · Warm Retro Editorial
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Fraunces:ital,opsz,wght@0,9..144,400;0,9..144,600;0,9..144,700;1,9..144,400&family=JetBrains+Mono:wght@400;500;600&family=Plus+Jakarta+Sans:wght@400;500;600;700&display=swap');

:root {
  /* Material 3 Expressive Tonal Palette (Warm Retro Editorial) */
  --md-sys-color-surface: #FAF7F2;
  --md-sys-color-surface-dim: #F2EBE0;
  --md-sys-color-surface-container-lowest: #FFFFFF;
  --md-sys-color-surface-container-low: #F6F0E6;
  --md-sys-color-surface-container: #EFE8DC;
  --md-sys-color-surface-container-high: #E8E0D2;
  --md-sys-color-surface-container-highest: #E1D8C9;
  
  --md-sys-color-on-surface: #1C1B1F;
  --md-sys-color-on-surface-variant: #4D4541;
  --md-sys-color-outline: #7F746E;
  --md-sys-color-outline-variant: #D3C4BC;

  /* Primary: Vintage Terracotta / Retro Brick */
  --md-sys-color-primary: #BA4422;
  --md-sys-color-primary-hover: #A0381A;
  --md-sys-color-primary-container: #FFDBCF;
  --md-sys-color-on-primary: #FFFFFF;
  --md-sys-color-on-primary-container: #3B0A00;

  /* Secondary: Slate Pine / Muted Teal */
  --md-sys-color-secondary: #355E63;
  --md-sys-color-secondary-hover: #294B4F;
  --md-sys-color-secondary-container: #D3E8EB;
  --md-sys-color-on-secondary: #FFFFFF;
  --md-sys-color-on-secondary-container: #002024;

  /* Tertiary: Vintage Amber / Brass */
  --md-sys-color-tertiary: #84531B;
  --md-sys-color-tertiary-container: #FFDDB9;
  --md-sys-color-on-tertiary: #FFFFFF;
  --md-sys-color-on-tertiary-container: #2D1600;

  /* Terminal & Code Dark Theme */
  --code-bg: #181B20;
  --code-surface: #21252C;
  --code-border: #313742;
  --code-text: #F1ECE4;
  --code-keyword: #E2795B;
  --code-string: #88C39E;
  --code-comment: #768194;
  --code-function: #76A9DF;

  /* Typography */
  --font-display: 'Fraunces', Georgia, serif;
  --font-body: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', SFMono-Regular, Consolas, monospace;

  /* Shapes & Radii (Material 3 Expressive) */
  --radius-xs: 6px;
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --radius-pill: 9999px;

  /* Elevation (Warm, soft ambient shadows) */
  --elevation-1: 0 1px 3px rgba(28, 27, 31, 0.05), 0 1px 2px rgba(28, 27, 31, 0.04);
  --elevation-2: 0 4px 8px rgba(28, 27, 31, 0.06), 0 1px 3px rgba(28, 27, 31, 0.04);
  --elevation-3: 0 12px 24px rgba(28, 27, 31, 0.08), 0 3px 6px rgba(28, 27, 31, 0.05);

  /* Motion */
  --transition-standard: 200ms cubic-bezier(0.2, 0.0, 0, 1.0);
  --transition-emphasized: 300ms cubic-bezier(0.05, 0.7, 0.1, 1.0);
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  background-color: var(--md-sys-color-surface);
  color: var(--md-sys-color-on-surface);
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: var(--font-body);
  line-height: 1.6;
  background-color: var(--md-sys-color-surface);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  position: relative;
  overflow-x: hidden;
}

/* Subtle Retro Paper Texture */
body::before {
  content: '';
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background-image: radial-gradient(rgba(28, 27, 31, 0.03) 1px, transparent 0);
  background-size: 24px 24px;
  pointer-events: none;
  z-index: 9999;
}

a {
  color: inherit;
  text-decoration: none;
}

img, svg {
  display: block;
  max-width: 100%;
}

button, input, textarea {
  font-family: inherit;
  font-size: inherit;
}

/* Layout Utilities */
.container {
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 clamp(1.25rem, 4vw, 2.5rem);
}

/* ==========================================================================
   Navigation Bar
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(250, 247, 242, 0.88);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--md-sys-color-outline-variant);
  transition: var(--transition-standard);
}

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

.brand-link {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.25rem;
  letter-spacing: -0.02em;
  color: var(--md-sys-color-on-surface);
  white-space: nowrap;
  flex-shrink: 0;
}

.brand-logo-icon {
  width: 34px;
  height: 34px;
  color: var(--md-sys-color-on-surface);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: clamp(14px, 1.8vw, 24px);
  list-style: none;
}

.nav-link {
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--md-sys-color-on-surface-variant);
  transition: color var(--transition-standard);
  white-space: nowrap;
}

.nav-link:hover {
  color: var(--md-sys-color-primary);
}

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

/* Material 3 Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 22px;
  border-radius: var(--radius-pill);
  font-weight: 600;
  font-size: 0.9375rem;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all var(--transition-standard);
  white-space: nowrap;
}

.btn-primary {
  background-color: var(--md-sys-color-primary);
  color: var(--md-sys-color-on-primary);
  box-shadow: var(--elevation-1);
}

.btn-primary:hover {
  background-color: var(--md-sys-color-primary-hover);
  box-shadow: var(--elevation-2);
  transform: translateY(-1px);
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-secondary {
  background-color: var(--md-sys-color-secondary-container);
  color: var(--md-sys-color-on-secondary-container);
}

.btn-secondary:hover {
  background-color: #c4dfe2;
  transform: translateY(-1px);
}

.btn-outlined {
  background-color: transparent;
  border-color: var(--md-sys-color-outline);
  color: var(--md-sys-color-on-surface);
}

.btn-outlined:hover {
  background-color: rgba(28, 27, 31, 0.04);
  border-color: var(--md-sys-color-on-surface);
}

.btn-github {
  background-color: var(--md-sys-color-surface-container);
  color: var(--md-sys-color-on-surface);
  border: 1px solid var(--md-sys-color-outline-variant);
}

.btn-github:hover {
  background-color: var(--md-sys-color-surface-container-high);
}

/* Mobile Nav Toggle */
.mobile-nav-toggle {
  display: none;
  background: none;
  border: none;
  padding: 8px;
  cursor: pointer;
  color: var(--md-sys-color-on-surface);
}

/* ==========================================================================
   Hero Section
   ========================================================================== */
.hero-section {
  padding: clamp(3.5rem, 8vw, 6rem) 0 2rem;
  text-align: center;
}

.hero-badge-wrap {
  display: inline-flex;
  margin-bottom: 24px;
}

.status-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background-color: var(--md-sys-color-surface-container);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--md-sys-color-on-surface-variant);
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: #2E7D32;
  display: inline-block;
  box-shadow: 0 0 0 3px rgba(46, 125, 50, 0.2);
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(2.25rem, 5.5vw, 4rem);
  font-weight: 700;
  line-height: 1.12;
  letter-spacing: -0.03em;
  color: var(--md-sys-color-on-surface);
  max-width: 920px;
  margin: 0 auto 24px;
}

.hero-title em {
  font-style: italic;
  color: var(--md-sys-color-primary);
  font-weight: 600;
}

.hero-title-prefix {
  display: block;
  font-family: var(--font-body);
  font-size: clamp(0.9375rem, 1.8vw, 1.1875rem);
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--md-sys-color-primary);
  margin-bottom: 12px;
}

.hero-subtitle {
  font-size: clamp(1.0625rem, 2vw, 1.25rem);
  color: var(--md-sys-color-on-surface-variant);
  max-width: 680px;
  margin: 0 auto 36px;
  font-weight: 400;
  line-height: 1.6;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 48px;
}

/* ==========================================================================
   Interactive Live Simulator Section
   ========================================================================== */
.simulator-section {
  padding: 2rem 0 clamp(3.5rem, 8vw, 6rem);
}

.simulator-wrapper {
  background-color: var(--md-sys-color-surface-container-low);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--radius-xl);
  padding: clamp(1.25rem, 3vw, 2.25rem);
  box-shadow: var(--elevation-2);
  position: relative;
  container-type: inline-size;
  container-name: simulator;
}

.sim-send-arrow {
  transition: transform var(--transition-standard);
  flex-shrink: 0;
}

.simulator-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
  flex-wrap: wrap;
  gap: 12px;
}

.simulator-tagline {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--md-sys-color-secondary);
}

.simulator-pill {
  padding: 4px 10px;
  background-color: var(--md-sys-color-secondary-container);
  color: var(--md-sys-color-on-secondary-container);
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 0.75rem;
}

.simulator-reset-btn {
  background: none;
  border: none;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--md-sys-color-on-surface-variant);
  cursor: pointer;
  text-decoration: underline;
}

.simulator-grid {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 20px;
  align-items: stretch;
}

/* App Window Mockup Card */
.app-window {
  background-color: var(--md-sys-color-surface-container-lowest);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--radius-lg);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  box-shadow: var(--elevation-1);
  transition: border-color var(--transition-standard);
}

.app-window.active-target {
  border-color: var(--md-sys-color-primary);
}

.window-titlebar {
  background-color: var(--md-sys-color-surface-container);
  padding: 10px 16px;
  border-bottom: 1px solid var(--md-sys-color-outline-variant);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.window-controls {
  display: flex;
  gap: 6px;
}

.dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background-color: #D3C4BC;
}

.window-info {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--md-sys-color-on-surface);
}

.window-role-tag {
  font-size: 0.6875rem;
  padding: 2px 8px;
  border-radius: var(--radius-pill);
  font-weight: 600;
  text-transform: uppercase;
}

.role-sender {
  background-color: var(--md-sys-color-tertiary-container);
  color: var(--md-sys-color-on-tertiary-container);
}

.role-receiver {
  background-color: var(--md-sys-color-secondary-container);
  color: var(--md-sys-color-on-secondary-container);
}

.window-body {
  padding: 20px;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

/* Form Controls Inside Simulator */
.sim-label {
  display: block;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--md-sys-color-on-surface-variant);
  margin-bottom: 6px;
}

.sim-input {
  width: 100%;
  padding: 10px 14px;
  background-color: var(--md-sys-color-surface-container-low);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  color: var(--md-sys-color-on-surface);
  transition: border-color var(--transition-standard);
}

.sim-input:focus {
  outline: none;
  border-color: var(--md-sys-color-primary);
  background-color: #FFFFFF;
}

.sim-textarea {
  min-height: 90px;
  resize: vertical;
  font-family: var(--font-mono);
  font-size: 0.8125rem;
}

.sim-chips {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.sample-chip {
  padding: 4px 10px;
  border-radius: var(--radius-pill);
  background-color: var(--md-sys-color-surface-container);
  border: 1px solid var(--md-sys-color-outline-variant);
  font-size: 0.75rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-standard);
}

.sample-chip:hover, .sample-chip.active {
  background-color: var(--md-sys-color-primary-container);
  border-color: var(--md-sys-color-primary);
  color: var(--md-sys-color-on-primary-container);
}

/* The Connecting Bridge Conduit */
.simulator-bridge-conduit {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: relative;
  width: 60px;
}

.conduit-line {
  width: 2px;
  height: 100%;
  background: repeating-linear-gradient(
    to bottom,
    var(--md-sys-color-outline-variant),
    var(--md-sys-color-outline-variant) 6px,
    transparent 6px,
    transparent 12px
  );
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
}

.bridge-pulse-badge {
  position: relative;
  z-index: 2;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background-color: var(--md-sys-color-surface-container-highest);
  border: 2px solid var(--md-sys-color-outline-variant);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--md-sys-color-on-surface);
  transition: all var(--transition-emphasized);
}

.bridge-pulse-badge.active-pulse {
  background-color: var(--md-sys-color-primary);
  color: #FFFFFF;
  border-color: var(--md-sys-color-primary);
  box-shadow: 0 0 0 6px rgba(186, 68, 34, 0.2);
  animation: pulse-ring 1.5s infinite;
}

@keyframes pulse-ring {
  0% { transform: scale(1); }
  50% { transform: scale(1.1); }
  100% { transform: scale(1); }
}

/* Receiver States inside Simulator */
.receiver-empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100%;
  text-align: center;
  color: var(--md-sys-color-on-surface-variant);
  padding: 30px 10px;
}

.receiver-empty-icon {
  width: 48px;
  height: 48px;
  margin-bottom: 12px;
  opacity: 0.5;
}

.preview-container {
  background-color: var(--md-sys-color-surface-container-low);
  border: 1px dashed var(--md-sys-color-outline);
  border-radius: var(--radius-sm);
  padding: 16px;
  position: relative;
}

.preview-tag {
  position: absolute;
  top: -10px;
  right: 12px;
  background-color: #E2795B;
  color: #FFFFFF;
  font-size: 0.6875rem;
  font-weight: 700;
  text-transform: uppercase;
  padding: 2px 8px;
  border-radius: var(--radius-pill);
}

.preview-content {
  font-size: 0.875rem;
  line-height: 1.5;
  color: var(--md-sys-color-on-surface);
  white-space: pre-wrap;
  max-height: 120px;
  overflow-y: auto;
}

.receiver-actions {
  display: flex;
  gap: 10px;
  margin-top: auto;
}

.preserved-success-card {
  background-color: #E7F3E8;
  border: 1px solid #75B77B;
  border-radius: var(--radius-sm);
  padding: 16px;
  text-align: center;
  color: #1E4E23;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

/* ==========================================================================
   Core Value Offerings (Bento Grid)
   ========================================================================== */
.principles-section {
  padding: clamp(3.5rem, 8vw, 6rem) 0;
}

.section-heading {
  text-align: center;
  margin-bottom: clamp(2.5rem, 5vw, 4rem);
}

.section-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--md-sys-color-primary);
  margin-bottom: 10px;
  display: inline-block;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.875rem, 4vw, 2.75rem);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--md-sys-color-on-surface);
  margin-bottom: 16px;
}

.section-description {
  font-size: 1.125rem;
  color: var(--md-sys-color-on-surface-variant);
  max-width: 620px;
  margin: 0 auto;
}

.bento-grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 24px;
  margin-bottom: 2.5rem;
}

.bento-card {
  background-color: var(--md-sys-color-surface-container-low);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--radius-xl);
  padding: clamp(1.75rem, 3vw, 2.5rem);
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: transform var(--transition-standard), box-shadow var(--transition-standard);
}

.bento-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--elevation-2);
}

.col-7 { grid-column: span 7; }
.col-5 { grid-column: span 5; }
.col-6 { grid-column: span 6; }

.bento-icon-wrapper {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background-color: var(--md-sys-color-surface-container-highest);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  color: var(--md-sys-color-primary);
}

.bento-title {
  font-family: var(--font-display);
  font-size: 1.375rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--md-sys-color-on-surface);
}

.bento-text {
  font-size: 0.9375rem;
  color: var(--md-sys-color-on-surface-variant);
  line-height: 1.6;
}

.bento-tag {
  align-self: flex-start;
  margin-top: auto;
  padding-top: 20px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--md-sys-color-secondary);
}

/* ==========================================================================
   How It Works (The 3-Step Rhythm)
   ========================================================================== */
.steps-section {
  padding: clamp(3.5rem, 8vw, 6rem) 0;
  background-color: var(--md-sys-color-surface-container-low);
  border-top: 1px solid var(--md-sys-color-outline-variant);
  border-bottom: 1px solid var(--md-sys-color-outline-variant);
}

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

.step-card {
  background-color: var(--md-sys-color-surface-container-lowest);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  display: flex;
  flex-direction: column;
}

.step-num {
  font-family: var(--font-display);
  font-size: 2.25rem;
  font-weight: 700;
  color: var(--md-sys-color-primary);
  margin-bottom: 16px;
  line-height: 1;
}

.step-title {
  font-size: 1.1875rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--md-sys-color-on-surface);
}

.step-desc {
  font-size: 0.9375rem;
  color: var(--md-sys-color-on-surface-variant);
  line-height: 1.6;
}

/* ==========================================================================
   Developer Quickstart (Tabbed Code)
   ========================================================================== */
.code-section {
  position: relative;
  padding: clamp(3.5rem, 8vw, 6rem) 0;
  overflow: hidden;
}

.code-section::before {
  content: '';
  position: absolute;
  top: 3rem;
  right: max(-8rem, -8vw);
  width: clamp(15rem, 30vw, 26rem);
  aspect-ratio: 1;
  border-radius: 46% 54% 65% 35% / 43% 39% 61% 57%;
  background: linear-gradient(145deg, var(--md-sys-color-primary-container), var(--md-sys-color-secondary-container));
  opacity: .48;
  filter: blur(1px);
  transform: rotate(12deg);
  pointer-events: none;
}

.quickstart-intro {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, .92fr) minmax(360px, 1.08fr);
  align-items: stretch;
  gap: clamp(1.5rem, 4vw, 4rem);
  margin-bottom: clamp(2rem, 5vw, 3.5rem);
}

.quickstart-copy {
  align-self: center;
  max-width: 34rem;
}

.quickstart-copy .section-title {
  max-width: 10ch;
  margin-bottom: 18px;
  font-size: clamp(2.35rem, 5vw, 4.6rem);
  line-height: .98;
  letter-spacing: -.045em;
}

.quickstart-lede {
  max-width: 32rem;
  color: var(--md-sys-color-on-surface-variant);
  font-size: clamp(1rem, 1.6vw, 1.125rem);
  line-height: 1.72;
}

.sdk-setup-card {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 18px;
  padding: clamp(1.4rem, 3vw, 2.1rem);
  color: var(--md-sys-color-on-surface);
  background:
    linear-gradient(145deg, color-mix(in srgb, var(--md-sys-color-secondary-container) 72%, var(--md-sys-color-surface-container-lowest)), var(--md-sys-color-surface-container-lowest));
  border: 1px solid color-mix(in srgb, var(--md-sys-color-secondary) 24%, var(--md-sys-color-outline-variant));
  border-radius: 12px var(--radius-xl) var(--radius-xl) var(--radius-xl);
  box-shadow: var(--elevation-2);
}

.sdk-step-index {
  display: grid;
  width: 48px;
  height: 48px;
  place-items: center;
  color: var(--md-sys-color-on-secondary);
  background: var(--md-sys-color-secondary);
  border-radius: 16px 16px 6px 16px;
  font-family: var(--font-mono);
  font-size: .8rem;
  font-weight: 700;
}

.sdk-setup-content {
  min-width: 0;
}

.sdk-setup-kicker {
  display: block;
  margin-bottom: 5px;
  color: var(--md-sys-color-secondary);
  font-family: var(--font-mono);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.sdk-setup-card h3 {
  margin-bottom: 10px;
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 2.4vw, 1.8rem);
  line-height: 1.15;
}

.sdk-setup-card p {
  color: var(--md-sys-color-on-surface-variant);
  font-size: .94rem;
  line-height: 1.62;
}

.sdk-setup-card p code,
.sdk-path code {
  font-family: var(--font-mono);
}

.sdk-setup-card p code {
  color: var(--md-sys-color-secondary);
  font-weight: 700;
}

.sdk-path {
  display: grid;
  gap: 4px;
  min-width: 0;
  margin: 18px 0 15px;
  padding: 12px 14px;
  background: color-mix(in srgb, var(--md-sys-color-surface-container-lowest) 82%, transparent);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--radius-sm);
}

.sdk-path span {
  color: var(--md-sys-color-outline);
  font-family: var(--font-mono);
  font-size: .66rem;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.sdk-path code {
  overflow: hidden;
  color: var(--md-sys-color-on-surface);
  font-size: clamp(.74rem, 1.5vw, .88rem);
  text-overflow: ellipsis;
  white-space: nowrap;
}

.sdk-source-link {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  color: var(--md-sys-color-secondary);
  font-size: .88rem;
  font-weight: 700;
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--md-sys-color-secondary) 38%, transparent);
  text-underline-offset: 4px;
}

.code-wrapper {
  position: relative;
  background-color: var(--code-bg);
  border: 1px solid var(--code-border);
  border-radius: var(--radius-xl) var(--radius-xl) 12px var(--radius-xl);
  overflow: hidden;
  box-shadow: 0 24px 52px rgb(28 27 31 / 16%), 0 3px 8px rgb(28 27 31 / 7%);
}

.code-header {
  background-color: var(--code-surface);
  padding: 14px 18px;
  border-bottom: 1px solid var(--code-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.code-tabs {
  display: flex;
  gap: 8px;
  min-width: 0;
  overflow-x: auto;
  scrollbar-width: none;
}

.code-tabs::-webkit-scrollbar { display: none; }

.code-tab {
  background: none;
  border: none;
  color: var(--code-comment);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 500;
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  cursor: pointer;
  transition: all var(--transition-standard);
  white-space: nowrap;
}

.code-tab:hover {
  color: var(--code-text);
}

.code-tab.active {
  background-color: color-mix(in srgb, var(--code-keyword) 28%, var(--code-surface));
  color: #FFFFFF;
}

.copy-btn {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: var(--code-text);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: 6px 12px;
  border-radius: var(--radius-pill);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all var(--transition-standard);
}

.copy-btn:hover {
  background: rgba(255, 255, 255, 0.16);
}

.code-block {
  min-height: 22rem;
  padding: clamp(1.4rem, 3vw, 2rem);
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--code-text);
  display: none;
  tab-size: 2;
}

.code-block.active {
  display: block;
}

/* Syntax Highlighting Tokens */
.code-block .tok-kw {
  color: var(--code-keyword);
  font-weight: 600;
}

.code-block .tok-str {
  color: var(--code-string);
}

.code-block .tok-fn {
  color: var(--code-function);
}

.code-block .tok-comment {
  color: var(--code-comment);
  font-style: italic;
}

.code-block .tok-tag {
  color: var(--code-keyword);
  font-weight: 600;
}

.code-block .tok-attr {
  color: #E5C07B;
}

.code-block .tok-key {
  color: #76A9DF;
}

.code-block .tok-num {
  color: #D19A66;
}

.code-block .tok-punct {
  color: #8B949E;
}

.code-block .tok-var {
  color: #E5C07B;
}

@media (max-width: 760px) {
  .quickstart-intro {
    grid-template-columns: 1fr;
  }

  .quickstart-copy .section-title {
    max-width: 12ch;
  }

  .sdk-setup-card {
    grid-template-columns: 1fr;
  }

  .code-header {
    align-items: stretch;
  }

  .code-tabs {
    flex-basis: 100%;
    order: 2;
  }

  .copy-btn {
    align-self: flex-end;
    margin-left: auto;
  }

  .code-block {
    min-height: 0;
    font-size: .78rem;
  }
}

/* ==========================================================================
   Community & Proposal Callout
   ========================================================================== */
.community-section {
  padding: clamp(2rem, 5vw, 4rem) 0 clamp(3.5rem, 8vw, 6rem);
}

.community-card {
  background: linear-gradient(135deg, var(--md-sys-color-surface-container-low), var(--md-sys-color-surface-container));
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--radius-xl);
  padding: clamp(2rem, 5vw, 4rem);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.community-content {
  max-width: 720px;
  margin: 0 auto;
}

.community-title {
  font-family: var(--font-display);
  font-size: clamp(2rem, 4vw, 2.75rem);
  font-weight: 700;
  margin-bottom: 20px;
  letter-spacing: -0.02em;
}

.community-text {
  font-size: 1.0625rem;
  color: var(--md-sys-color-on-surface-variant);
  line-height: 1.7;
  margin-bottom: 32px;
}

.community-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

/* ==========================================================================
   Showcase / Reference Implementations
   ========================================================================== */
.showcase-section {
  padding: 0 0 clamp(3.5rem, 8vw, 6rem);
}

.showcase-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.showcase-card {
  background-color: var(--md-sys-color-surface-container-lowest);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--radius-lg);
  padding: 28px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.showcase-badge {
  align-self: flex-start;
  padding: 4px 10px;
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  background-color: var(--md-sys-color-primary-container);
  color: var(--md-sys-color-on-primary-container);
}

.showcase-name {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--md-sys-color-on-surface);
}

.showcase-desc {
  font-size: 0.9375rem;
  color: var(--md-sys-color-on-surface-variant);
  line-height: 1.6;
}

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer {
  background-color: var(--md-sys-color-surface-container);
  border-top: 1px solid var(--md-sys-color-outline-variant);
  padding: 60px 0 40px;
  margin-top: auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-brand-title {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-size: 1.1875rem;
  font-weight: 700;
}

.footer-desc {
  font-size: 0.875rem;
  color: var(--md-sys-color-on-surface-variant);
  max-width: 360px;
  line-height: 1.6;
}

.footer-col-title {
  font-size: 0.875rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--md-sys-color-on-surface);
  margin-bottom: 16px;
}

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

.footer-link {
  font-size: 0.875rem;
  color: var(--md-sys-color-on-surface-variant);
  transition: color var(--transition-standard);
}

.footer-link:hover {
  color: var(--md-sys-color-primary);
}

.footer-bottom {
  border-top: 1px solid var(--md-sys-color-outline-variant);
  padding-top: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 0.8125rem;
  color: var(--md-sys-color-on-surface-variant);
}

/* ==========================================================================
   Responsive Breakpoints
   ========================================================================== */
@media (max-width: 960px), (orientation: portrait) and (max-width: 1100px), (max-aspect-ratio: 1/1) and (max-width: 1100px) {
  .simulator-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .sim-send-arrow {
    transform: rotate(90deg);
  }

  .simulator-bridge-conduit {
    width: 100%;
    height: 44px;
  }

  .conduit-line {
    width: 100%;
    height: 2px;
    top: 50%;
    left: 0;
    transform: translateY(-50%);
    background: repeating-linear-gradient(
      to right,
      var(--md-sys-color-outline-variant),
      var(--md-sys-color-outline-variant) 6px,
      transparent 6px,
      transparent 12px
    );
  }

  .col-7, .col-5, .col-6 {
    grid-column: span 12;
  }

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

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

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

@container simulator (max-width: 820px) {
  .simulator-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .sim-send-arrow {
    transform: rotate(90deg);
  }

  .simulator-bridge-conduit {
    width: 100%;
    height: 44px;
  }

  .conduit-line {
    width: 100%;
    height: 2px;
    top: 50%;
    left: 0;
    transform: translateY(-50%);
    background: repeating-linear-gradient(
      to right,
      var(--md-sys-color-outline-variant),
      var(--md-sys-color-outline-variant) 6px,
      transparent 6px,
      transparent 12px
    );
  }
}

@media (max-width: 880px) {
  .nav-links {
    display: none;
  }
  
  .mobile-nav-toggle {
    display: block;
  }

  .nav-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 72px;
    left: 0;
    right: 0;
    background-color: var(--md-sys-color-surface);
    border-bottom: 1px solid var(--md-sys-color-outline-variant);
    padding: 24px;
    box-shadow: var(--elevation-3);
  }
}

/* ==========================================================================
   Ecosystem & Live External Sender
   ========================================================================== */
.ecosystem-section {
  padding: clamp(3.5rem, 8vw, 6rem) 0;
  background-color: var(--md-sys-color-surface-container-low);
  border-top: 1px solid var(--md-sys-color-outline-variant);
  border-bottom: 1px solid var(--md-sys-color-outline-variant);
}

.apps-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-bottom: 48px;
}

.app-card {
  background-color: var(--md-sys-color-surface-container-lowest);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--radius-xl);
  padding: clamp(1.5rem, 3vw, 2.25rem);
  display: flex;
  flex-direction: column;
  gap: 16px;
  box-shadow: var(--elevation-1);
  transition: transform var(--transition-standard), box-shadow var(--transition-standard);
}

.app-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--elevation-2);
}

.app-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.app-card-title-group {
  display: flex;
  align-items: center;
  gap: 12px;
}

.app-avatar {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background-color: var(--md-sys-color-surface-container-highest);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--md-sys-color-primary);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.25rem;
}

.app-card-name {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--md-sys-color-on-surface);
}

.app-card-domain {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--md-sys-color-outline);
}

.app-cap-chips {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.cap-chip {
  padding: 3px 8px;
  border-radius: var(--radius-pill);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  font-weight: 600;
  text-transform: uppercase;
  background-color: var(--md-sys-color-secondary-container);
  color: var(--md-sys-color-on-secondary-container);
}

.cap-chip-amber {
  background-color: var(--md-sys-color-tertiary-container);
  color: var(--md-sys-color-on-tertiary-container);
}

.live-sender-box {
  background-color: var(--md-sys-color-surface-container-lowest);
  border: 2px solid var(--md-sys-color-primary);
  border-radius: var(--radius-xl);
  padding: clamp(1.75rem, 3.5vw, 2.75rem);
  box-shadow: var(--elevation-2);
}

.live-sender-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
  flex-wrap: wrap;
  gap: 16px;
}

.live-sender-title {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--md-sys-color-on-surface);
}

.live-sender-desc {
  font-size: 0.9375rem;
  color: var(--md-sys-color-on-surface-variant);
  max-width: 680px;
}

.live-sender-form {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-top: 20px;
}

.live-sender-full {
  grid-column: span 2;
}

.live-sender-status {
  padding: 12px 16px;
  background-color: var(--md-sys-color-surface-container);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  color: var(--md-sys-color-on-surface);
  display: flex;
  align-items: center;
  gap: 10px;
}

.live-sender-status.error {
  background-color: #ffdad6;
  border-color: #ba1a1a;
  color: #410002;
}

#live-oab-share {
  --oab-share-font-family: var(--font-body);
  --oab-share-accent: var(--md-sys-color-primary);
  --oab-share-accent-color: var(--md-sys-color-on-primary);
  --oab-share-surface: var(--md-sys-color-surface-container-lowest);
  --oab-share-surface-raised: var(--md-sys-color-surface-container-low);
  --oab-share-color: var(--md-sys-color-on-surface);
  --oab-share-muted-color: var(--md-sys-color-on-surface-variant);
  --oab-share-border-color: var(--md-sys-color-outline-variant);
  --oab-share-danger: #ba1a1a;
  --oab-share-focus: var(--md-sys-color-secondary);
  --oab-share-radius: var(--radius-lg);
  --oab-share-shadow: var(--elevation-3);
  --oab-share-backdrop: rgb(28 27 31 / 55%);
}

@media (max-width: 960px) {
  .apps-grid {
    grid-template-columns: 1fr;
  }
  .live-sender-form {
    grid-template-columns: 1fr;
  }
  .live-sender-full {
    grid-column: span 1;
  }
}

/* ==========================================================================
   FAQ Section
   ========================================================================== */
.faq-section {
  padding: 5rem 0;
  background-color: var(--md-sys-color-surface-container-low);
  border-top: 1px solid var(--md-sys-color-outline-variant);
  border-bottom: 1px solid var(--md-sys-color-outline-variant);
}

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

.faq-accordion {
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin-top: 36px;
}

.faq-item {
  background-color: var(--md-sys-color-surface-container-lowest);
  border: 1px solid var(--md-sys-color-outline-variant);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color var(--transition-standard), box-shadow var(--transition-standard);
}

.faq-item:hover {
  border-color: var(--md-sys-color-outline);
  box-shadow: var(--elevation-1);
}

.faq-item[open] {
  border-color: var(--md-sys-color-primary);
  box-shadow: var(--elevation-2);
}

.faq-summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  font-family: var(--font-display);
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--md-sys-color-on-surface);
  cursor: pointer;
  user-select: none;
  list-style: none;
  transition: color var(--transition-standard);
}

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

.faq-summary:hover {
  color: var(--md-sys-color-primary);
}

.faq-summary:focus-visible {
  outline: 2px solid var(--md-sys-color-primary);
  outline-offset: -2px;
}

.faq-icon {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  margin-left: 16px;
  border-radius: var(--radius-pill);
  background-color: var(--md-sys-color-surface-container);
  color: var(--md-sys-color-on-surface-variant);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform var(--transition-emphasized), background-color var(--transition-standard), color var(--transition-standard);
}

.faq-item[open] .faq-icon {
  transform: rotate(180deg);
  background-color: var(--md-sys-color-primary-container);
  color: var(--md-sys-color-on-primary-container);
}

.faq-answer {
  padding: 0 24px 20px;
  font-size: 0.9375rem;
  line-height: 1.7;
  color: var(--md-sys-color-on-surface-variant);
}

.faq-item[open] .faq-answer {
  border-top: 1px solid var(--md-sys-color-surface-container);
  padding-top: 16px;
}

.faq-answer p:not(:last-child) {
  margin-bottom: 12px;
}

.faq-answer code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  padding: 2px 6px;
  border-radius: var(--radius-xs);
  background-color: var(--md-sys-color-surface-container);
  color: var(--md-sys-color-on-surface);
}

.faq-answer a {
  color: var(--md-sys-color-primary);
  text-decoration: underline;
  text-underline-offset: 3px;
}