/* ===================================================================
   style.css — Jarvis Download Landing Page
   Dark theme, zero external dependencies, mobile-first
   =================================================================== */

/* ----- CSS Custom Properties ----- */
:root {
  --bg-primary:    #0d1117;
  --bg-secondary:  #161b22;
  --bg-tertiary:   #21262d;
  --bg-card:       #1c2128;
  --border-color:  #30363d;
  --border-subtle: #21262d;

  --text-primary:   #e6edf3;
  --text-secondary: #8b949e;
  --text-muted:     #6e7681;

  --accent-blue:  #58a6ff;
  --accent-green: #238636;
  --accent-green-hover: #2ea043;
  --accent-green-active: #1a7f37;

  --code-bg: #161b22;
  --code-text: #79c0ff;

  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.6);

  --transition-fast: 0.15s ease;
  --transition-med:  0.25s ease;

  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue',
               Arial, 'Noto Sans', sans-serif;
  --font-mono: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, Courier, monospace;

  --max-width: 860px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--accent-blue);
  text-decoration: none;
  transition: color var(--transition-fast), opacity var(--transition-fast);
}

a:hover {
  color: #79c0ff;
  text-decoration: underline;
}

/* ----- Layout ----- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* ----- Header ----- */
.site-header {
  border-bottom: 1px solid var(--border-color);
  padding: 20px 0;
  background-color: var(--bg-secondary);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.logo-area {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, #1f6feb 0%, #388bfd 50%, #58a6ff 100%);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  font-weight: 700;
  color: #fff;
  letter-spacing: 0;
  flex-shrink: 0;
  box-shadow: var(--shadow-sm);
}

.logo-text {
  display: flex;
  flex-direction: column;
}

.logo-name {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: 0;
  line-height: 1.2;
}

.logo-tagline {
  font-size: 0.78rem;
  color: var(--text-secondary);
  font-weight: 400;
}

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

.version-badge {
  display: inline-block;
  background-color: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  color: var(--accent-blue);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 20px;
  font-family: var(--font-mono);
  letter-spacing: 0.3px;
  min-width: 60px;
  text-align: center;
}

.version-badge.badge-coming-soon {
  color: var(--text-muted);
  border-color: var(--border-subtle);
}

/* Language toggle */
.lang-toggle {
  display: inline-flex;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.lang-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 0.75rem;
  font-weight: 500;
  padding: 4px 10px;
  cursor: pointer;
  font-family: var(--font-sans);
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.lang-btn:hover {
  color: var(--text-primary);
  background-color: var(--bg-tertiary);
}

.lang-btn.active {
  color: var(--accent-blue);
  background-color: var(--bg-tertiary);
}

.lang-btn + .lang-btn {
  border-left: 1px solid var(--border-color);
}

.github-link {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 500;
  transition: color var(--transition-fast);
}

.github-link:hover {
  color: var(--text-primary);
  text-decoration: none;
}

.github-link svg {
  flex-shrink: 0;
}

/* ----- Hero Section ----- */
.hero {
  padding: 56px 0 44px;
  text-align: left;
  background:
    linear-gradient(180deg, rgba(88, 166, 255, 0.045) 0%, transparent 42%),
    var(--bg-primary);
}

.hero-container {
  max-width: 1120px;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(420px, 1.08fr);
  gap: 44px;
  align-items: center;
}

.hero-copy {
  min-width: 0;
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  color: var(--accent-blue);
  border: 1px solid rgba(88, 166, 255, 0.32);
  background-color: rgba(88, 166, 255, 0.08);
  border-radius: 999px;
  padding: 5px 12px;
  font-size: 0.76rem;
  font-weight: 600;
  margin-bottom: 18px;
}

.hero-title {
  font-size: clamp(2.2rem, 5vw, 4.1rem);
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: 0;
  line-height: 1.04;
  margin-bottom: 20px;
  max-width: 620px;
}

.hero-title .highlight {
  color: var(--accent-blue);
}

.hero-subtitle {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 0 28px;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: 12px;
}

.secondary-demo-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  color: var(--accent-blue);
  border: 1px solid rgba(88, 166, 255, 0.28);
  background-color: rgba(88, 166, 255, 0.05);
  border-radius: var(--radius-md);
  padding: 0 16px;
  font-size: 0.92rem;
  font-weight: 600;
}

.secondary-demo-link:hover {
  color: #79c0ff;
  border-color: rgba(88, 166, 255, 0.55);
  background-color: rgba(88, 166, 255, 0.08);
  text-decoration: none;
}

.hero-proof {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 18px;
}

.hero-proof span {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  border: 1px solid var(--border-color);
  background-color: rgba(22, 27, 34, 0.76);
  color: var(--text-secondary);
  border-radius: 999px;
  padding: 4px 10px;
  font-size: 0.76rem;
  font-weight: 600;
}

.hero-visual {
  min-width: 0;
  border: 1px solid rgba(88, 166, 255, 0.22);
  border-radius: var(--radius-lg);
  background-color: #05070a;
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.44);
  overflow: hidden;
}

.hero-demo-video {
  width: 100%;
  aspect-ratio: 16 / 9;
  display: block;
  object-fit: contain;
  background-color: #000;
}

/* Primary Download Button */
.primary-download {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background-color: var(--accent-green);
  color: #fff;
  font-size: 1rem;
  font-weight: 600;
  padding: 14px 28px;
  border-radius: var(--radius-md);
  text-decoration: none;
  transition: background-color var(--transition-fast),
              transform var(--transition-fast),
              box-shadow var(--transition-fast);
  box-shadow: 0 0 0 1px rgba(35, 134, 54, 0.4), var(--shadow-md);
  margin-bottom: 0;
  position: relative;
  overflow: hidden;
  min-height: 58px;
}

.primary-download::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(255,255,255,0.06) 0%, transparent 100%);
  pointer-events: none;
}

.primary-download:hover {
  background-color: var(--accent-green-hover);
  transform: translateY(-2px);
  box-shadow: 0 0 0 1px rgba(46, 160, 67, 0.5), var(--shadow-lg);
  color: #fff;
  text-decoration: none;
}

.primary-download:active {
  background-color: var(--accent-green-active);
  transform: translateY(0);
}

.primary-download.btn-disabled {
  background-color: var(--bg-tertiary);
  color: var(--text-muted);
  cursor: not-allowed;
  box-shadow: none;
  pointer-events: none;
}

.btn-icon {
  font-size: 1.2rem;
  line-height: 1;
}

.btn-label {
  /* placeholder updated by detect.js */
}

.btn-sub {
  display: block;
  font-size: 0.72rem;
  font-weight: 400;
  color: rgba(255,255,255,0.65);
  margin-top: 1px;
}

/* Download size hint */
.download-meta {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 14px;
}

/* Other platforms */
.other-platforms {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-start;
  align-items: center;
  gap: 10px;
  margin-bottom: 0;
}

.other-platforms-label {
  width: auto;
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-bottom: 0;
}

.platform-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  font-size: 0.82rem;
  font-weight: 500;
  padding: 7px 14px;
  border-radius: var(--radius-sm);
  transition: border-color var(--transition-fast),
              color var(--transition-fast),
              background-color var(--transition-fast);
}

.platform-link:hover {
  border-color: var(--accent-blue);
  color: var(--accent-blue);
  background-color: rgba(88, 166, 255, 0.06);
  text-decoration: none;
}

.platform-link.current-platform {
  border-color: var(--accent-blue);
  color: var(--accent-blue);
}

.platform-link.link-disabled {
  pointer-events: none;
  opacity: 0.4;
}

/* ----- Divider ----- */
.section-divider {
  border: none;
  border-top: 1px solid var(--border-color);
  margin: 0;
}

/* ----- Install Steps Section ----- */
.install-section {
  padding: 52px 0;
}

.section-heading {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text-primary);
  text-align: center;
  margin-bottom: 8px;
}

.section-subheading {
  font-size: 0.9rem;
  color: var(--text-secondary);
  text-align: center;
  margin-bottom: 36px;
}

/* Steps */
.steps {
  display: flex;
  flex-direction: column;
  gap: 20px;
  margin-bottom: 40px;
}

.step {
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 16px;
  align-items: flex-start;
}

.step-number {
  width: 44px;
  height: 44px;
  background: var(--bg-secondary);
  border: 2px solid var(--accent-blue);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  font-weight: 700;
  color: var(--accent-blue);
  flex-shrink: 0;
}

.step-content {
  padding-top: 2px;
}

.step-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.step-badge {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--accent-blue);
  border: 1px solid var(--accent-blue);
  border-radius: 4px;
  padding: 1px 6px;
  vertical-align: middle;
  margin-left: 6px;
}

.step-desc {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.55;
}

/* ----- Tab System ----- */
.tab-container {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.tab-nav {
  display: flex;
  border-bottom: 1px solid var(--border-color);
  background-color: var(--bg-secondary);
}

.tab-btn {
  padding: 10px 20px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  cursor: pointer;
  transition: color var(--transition-fast), border-color var(--transition-fast);
  font-family: var(--font-sans);
  display: flex;
  align-items: center;
  gap: 6px;
}

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

.tab-btn.active {
  color: var(--accent-blue);
  border-bottom-color: var(--accent-blue);
}

.tab-panel {
  display: none;
  padding: 20px;
}

.tab-panel.active {
  display: block;
}

/* Code blocks */
.code-block {
  background-color: var(--code-bg);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 14px 16px;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--code-text);
  overflow-x: auto;
  margin-top: 8px;
  line-height: 1.6;
  white-space: pre;
}

.code-comment {
  color: var(--text-muted);
  font-style: italic;
}

/* ----- Footer ----- */
.site-footer {
  margin-top: auto;
  border-top: 1px solid var(--border-color);
  background-color: var(--bg-secondary);
  padding: 24px 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-links {
  display: flex;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}

.footer-link {
  color: var(--text-secondary);
  font-size: 0.82rem;
  display: flex;
  align-items: center;
  gap: 5px;
  transition: color var(--transition-fast);
}

.footer-link:hover {
  color: var(--text-primary);
  text-decoration: none;
}

.footer-right {
  font-size: 0.78rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 6px;
}

.cf-logo {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  color: #f6821f;
  font-weight: 600;
  font-size: 0.78rem;
}

/* ----- Demo Showcase Section ----- */
.demo-showcase {
  padding: 64px 0;
}

.demo-showcase .section-heading {
  margin-bottom: 8px;
}

.demo-showcase .section-subheading {
  margin-bottom: 56px;
}

/* Individual demo item — chess layout */
.demo-item {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 40px;
  align-items: center;
  margin-bottom: 64px;
}

.demo-item:last-child {
  margin-bottom: 0;
}

.demo-item--reversed {
  grid-template-columns: 1fr 1.15fr;
}

.demo-item--reversed .demo-media {
  order: 2;
}

.demo-item--reversed .demo-text {
  order: 1;
}

/* Media container (placeholder or real asset) */
.demo-media {
  width: 100%;
}

.demo-placeholder {
  aspect-ratio: 16 / 10;
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
  position: relative;
  overflow: hidden;
  transition: border-color var(--transition-med), box-shadow var(--transition-med);
}

/* Subtle gradient shimmer — signals "content coming" */
.demo-placeholder::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    transparent 0%,
    rgba(88, 166, 255, 0.03) 40%,
    rgba(88, 166, 255, 0.06) 50%,
    rgba(88, 166, 255, 0.03) 60%,
    transparent 100%
  );
  pointer-events: none;
}

.demo-placeholder:hover {
  border-color: var(--accent-blue);
  box-shadow: 0 0 0 1px rgba(88, 166, 255, 0.1), var(--shadow-md);
}

.demo-placeholder-icon {
  width: 48px;
  height: 48px;
  background-color: rgba(88, 166, 255, 0.1);
  border: 1px solid rgba(88, 166, 255, 0.2);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  color: var(--accent-blue);
  transition: background-color var(--transition-fast);
}

.demo-placeholder:hover .demo-placeholder-icon {
  background-color: rgba(88, 166, 255, 0.15);
}

.demo-placeholder-label {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 500;
}

/* When real media replaces placeholder: img/video inside .demo-media */
.demo-media img,
.demo-media video {
  width: 100%;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-lg);
  display: block;
}

.demo-video {
  aspect-ratio: 16 / 10;
  background-color: #000;
  object-fit: contain;
}

/* Text column */
.demo-text {
  padding: 8px 0;
}

.demo-badge {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--accent-blue);
  border: 1px solid rgba(88, 166, 255, 0.3);
  background-color: rgba(88, 166, 255, 0.08);
  border-radius: 20px;
  padding: 3px 12px;
  margin-bottom: 16px;
  letter-spacing: 0;
  text-transform: uppercase;
}

.demo-title {
  font-size: clamp(1.2rem, 3vw, 1.5rem);
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.3;
  margin-bottom: 12px;
  letter-spacing: 0;
}

.demo-desc {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ----- Pulse animation on primary button ----- */
@keyframes pulse-border {
  0%, 100% { box-shadow: 0 0 0 1px rgba(35, 134, 54, 0.4), 0 4px 12px rgba(0,0,0,0.5); }
  50%       { box-shadow: 0 0 0 4px rgba(35, 134, 54, 0.15), 0 4px 12px rgba(0,0,0,0.5); }
}

.primary-download:not(.btn-disabled) {
  animation: none;
}

.primary-download:hover,
.primary-download:focus {
  animation: none;
}

/* ----- Responsive ----- */
@media (max-width: 980px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }

  .hero-title,
  .hero-subtitle {
    max-width: 680px;
  }

  .hero-visual {
    max-width: 680px;
  }
}

@media (max-width: 768px) {
  .hero {
    padding: 42px 0 38px;
  }

  .hero-title {
    font-size: clamp(2rem, 11vw, 3rem);
  }

  .hero-subtitle {
    font-size: 1rem;
    margin-bottom: 24px;
  }

  .hero-actions {
    align-items: stretch;
  }

  .primary-download,
  .secondary-demo-link {
    justify-content: center;
  }

  .hero-visual {
    border-radius: var(--radius-md);
  }

  .demo-item,
  .demo-item--reversed {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .demo-item--reversed .demo-media {
    order: 0;
  }

  .demo-item--reversed .demo-text {
    order: 0;
  }

  .demo-item {
    margin-bottom: 48px;
  }

  .demo-showcase {
    padding: 48px 0;
  }

  .demo-showcase .section-subheading {
    margin-bottom: 40px;
  }
}

@media (max-width: 600px) {
  .hero {
    padding: 28px 0 26px;
  }

  .hero-grid {
    gap: 22px;
  }

  .hero-eyebrow {
    margin-bottom: 14px;
    padding: 4px 10px;
    font-size: 0.72rem;
  }

  .hero-title {
    font-size: clamp(1.75rem, 9vw, 2.55rem);
    line-height: 1.08;
    margin-bottom: 14px;
  }

  .hero-subtitle {
    font-size: 0.95rem;
    line-height: 1.55;
    margin-bottom: 18px;
  }

  .hero-actions {
    gap: 10px;
    margin-bottom: 10px;
  }

  .header-inner {
    flex-wrap: wrap;
  }

  .header-meta .github-link span {
    display: none;
  }

  .primary-download {
    padding: 12px 20px;
    font-size: 0.92rem;
    width: 100%;
  }

  .secondary-demo-link {
    width: 100%;
    min-height: 42px;
  }

  .other-platforms {
    gap: 8px;
  }

  .other-platforms-label {
    width: 100%;
  }

  .download-meta {
    margin-bottom: 10px;
  }

  .hero-proof {
    gap: 6px;
    margin-bottom: 12px;
  }

  .hero-proof span {
    min-height: 24px;
    padding: 2px 8px;
    font-size: 0.72rem;
  }

  .platform-link {
    padding: 6px 10px;
    font-size: 0.78rem;
  }

  .step {
    grid-template-columns: 38px 1fr;
    gap: 12px;
  }

  .step-number {
    width: 38px;
    height: 38px;
    font-size: 0.9rem;
  }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .tab-btn {
    padding: 10px 14px;
    font-size: 0.8rem;
  }
}

@media (max-width: 420px) {
  .logo-tagline {
    display: none;
  }
}